Upgrade libpng to v1.6.38

This project was upgraded with external_updater.
Usage: tools/external_updater/updater.sh update libpng
For more info, check https://cs.android.com/android/platform/superproject/+/master:tools/external_updater/README.md

Test: TreeHugger
Change-Id: Id1ea88761f7874779d7fd531dd14489032d17a61
diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 0000000..88dc11e
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,69 @@
+version: 1.6.x-{build}
+
+branches:
+  except:
+    - /libpng[0-1][0-7]/
+
+image:
+  - Visual Studio 2022
+
+shallow_clone: true
+
+environment:
+  matrix:
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: x86
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: x64
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: arm64
+      CI_NO_TEST: 1
+    - TOOLCHAIN: msys2
+      AUTOMATION: cmake
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: cmake
+      ARCH: x86_64
+    - TOOLCHAIN: msys2
+      AUTOMATION: autotools
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: autotools
+      ARCH: x86_64
+    - TOOLCHAIN: msys2
+      AUTOMATION: legacy
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: legacy
+      ARCH: x86_64
+
+install:
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe integrate install'
+
+before_build:
+  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_VARS=-DCMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
+  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_GENERATOR=Visual Studio 17 2022'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x86" set CI_CMAKE_GENERATOR_PLATFORM=Win32'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x64" set CI_CMAKE_GENERATOR_PLATFORM=x64'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_GENERATOR_PLATFORM=ARM64'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" set CI_CMAKE_GENERATOR=Unix Makefiles'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="i686" set PATH=C:\msys64\mingw32\bin;%PATH%'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="x86_64" set PATH=C:\msys64\mingw64\bin;%PATH%'
+  - 'if "%TOOLCHAIN%"=="msys2" set CI_CC=%ARCH%-w64-mingw32-gcc'
+  - 'set CI_CMAKE_BUILD_FLAGS=--parallel 2'
+  - 'set CI_CTEST_FLAGS=--parallel 2'
+  - 'set CI_MAKE_FLAGS=-j2'
+  - 'set CI_LEGACY_MAKEFILES=scripts/makefile.gcc scripts/makefile.msys scripts/makefile.std'
+
+build_script:
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_cmake.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_cmake.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="autotools" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_autotools.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="legacy" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_legacy.sh"'
+
+cache:
+  - C:\tools\vcpkg\installed
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e280e7c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,75 @@
+# Prerequisites
+*.d
+
+# Precompiled headers
+*.gch
+*.pch
+
+# Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Linker output files
+*.exp
+*.ilk
+*.map
+
+# Compiled dynamic libraries
+*.dll
+*.dylib
+*.so
+*.so.*
+
+# Compiled static libraries
+*.a
+*.la
+*.lai
+*.lib
+
+# Compiled executables
+*.app/
+*.exe
+
+# Debug files
+*.dSYM/
+*.idb
+*.pdb
+*.su
+
+# Libpng configuration and build artifacts
+.deps/
+.dirstamp
+Makefile
+config.h
+config.log
+config.status
+libpng-config
+libpng.pc
+libpng.vers
+libpng16-config
+libpng16.pc
+libtool
+pnglibconf.[ch]
+pnglibconf.dfn
+pnglibconf.out
+pnglibconf.pre
+pngprefix.h
+stamp-h1
+vers.out
+
+# Libpng test artifacts
+png-fix-itxt
+pngcp
+pngfix
+pngimage
+pngstest
+pngtest
+pngunknown
+pngvalid
+timepng
+pngout.png
+
+# Libpng CI artifacts
+out/
diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..70457cd
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,45 @@
+branches:
+  except:
+    - /libpng[0-1][0-7]/
+
+language: c
+
+os:
+  - freebsd
+  - linux
+  - osx
+
+compiler:
+  - clang
+  - gcc
+
+env:
+  - AUTOMATION=cmake CI_NO_TEST=1
+  - AUTOMATION=cmake CI_CMAKE_VARS="-DPNG_HARDWARE_OPTIMIZATIONS=ON" CI_SANITIZERS="address,undefined"
+  - AUTOMATION=cmake CI_CMAKE_VARS="-DPNG_HARDWARE_OPTIMIZATIONS=OFF" CI_SANITIZERS="address,undefined"
+  - AUTOMATION=autotools CI_NO_TEST=1
+  - AUTOMATION=autotools CI_CONFIGURE_FLAGS="--enable-hardware-optimizations"
+  - AUTOMATION=autotools CI_CONFIGURE_FLAGS="--disable-hardware-optimizations"
+  - AUTOMATION=legacy CI_NO_TEST=1
+  - AUTOMATION=legacy CI_SANITIZERS="address,undefined"
+
+matrix:
+  include:
+    - os: osx
+      compiler: cc
+      env: AUTOMATION=cmake CI_CMAKE_GENERATOR=Xcode
+  exclude:
+    - os: freebsd
+      compiler: gcc
+    - os: osx
+      compiler: gcc
+
+before_script:
+  - 'export CI_CMAKE_BUILD_FLAGS="--parallel 2"'
+  - 'export CI_CTEST_FLAGS="--parallel 2"'
+  - 'export CI_MAKE_FLAGS=-j2'
+  - 'export CI_CC=$TRAVIS_COMPILER'
+  - 'export CI_LEGACY_MAKEFILES="scripts/makefile.$TRAVIS_COMPILER scripts/makefile.std"'
+
+script:
+  - './ci/ci_$AUTOMATION.sh'
diff --git a/ANNOUNCE b/ANNOUNCE
index ecf9c70..9c9bb18 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
-libpng 1.6.37 - April 14, 2019
-==============================
+libpng 1.6.38 - September 14, 2022
+==================================
 
 This is a public release of libpng, intended for use in production code.
 
@@ -9,13 +9,13 @@
 
 Source files with LF line endings (for Unix/Linux):
 
- * libpng-1.6.37.tar.xz (LZMA-compressed, recommended)
- * libpng-1.6.37.tar.gz
+ * libpng-1.6.38.tar.xz (LZMA-compressed, recommended)
+ * libpng-1.6.38.tar.gz
 
 Source files with CRLF line endings (for Windows):
 
- * lp1637.7z (LZMA-compressed, recommended)
- * lp1637.zip
+ * lp1638.7z (LZMA-compressed, recommended)
+ * lp1638.zip
 
 Other information:
 
@@ -25,20 +25,13 @@
  * TRADEMARK.md
 
 
-Changes since the previous public release (version 1.6.36)
+Changes since the previous public release (version 1.6.37)
 ----------------------------------------------------------
 
- * Fixed a use-after-free vulnerability (CVE-2019-7317) in png_image_free.
- * Fixed a memory leak in the ARM NEON implementation of png_do_expand_palette.
- * Fixed a memory leak in pngtest.c.
- * Fixed two vulnerabilities (CVE-2018-14048, CVE-2018-14550) in
-   contrib/pngminus; refactor.
- * Changed the license of contrib/pngminus to MIT; refresh makefile and docs.
-   (Contributed by Willem van Schaik)
- * Fixed a typo in the libpng license v2.
-   (Contributed by Miguel Ojeda)
- * Added makefiles for AddressSanitizer-enabled builds.
- * Cleaned up various makefiles.
+ * Added configurations and scripts for continuous integration.
+ * Fixed various errors in the handling of tRNS, hIST and eXIf.
+ * Implemented many stability improvements across all platforms.
+ * Updated the internal documentation.
 
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
diff --git a/AUTHORS b/AUTHORS
index 79a3d10..e6a58d2 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -20,7 +20,9 @@
  * Mans Rullgard
  * Matt Sarett
  * Mike Klein
+ * Pascal Massimino
  * Paul Schmidt
+ * Qiang Zhou
  * Sam Bushell
  * Samuel Williams
  * Simon-Pierre Cadieux
@@ -35,10 +37,12 @@
  * Google Inc.
    - Matt Sarett
    - Mike Klein
+   - Dan Field
+   - Sami Boukortt
 
 The build projects, the build scripts, the test scripts, and other
-files in the "projects", "scripts" and "tests" directories, have other
-copyright owners, but are released under the libpng license.
+files in the "ci", "projects", "scripts" and "tests" directories, have
+other copyright owners, but are released under the libpng license.
 
 Some files in the "contrib" directory, and some tools-generated files
 that are distributed with libpng, have other copyright owners, and are
diff --git a/CHANGES b/CHANGES
index f0b0a93..9a86869 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2295,7 +2295,7 @@
   Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri)
 
 Version 1.4.0beta59 [May 15, 2009]
-  Reformated sources in libpng style (3-space intentation, comment format)
+  Reformated sources in libpng style (3-space indentation, comment format)
   Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG)
   Added sections about the git repository and our coding style to the
     documentation
@@ -3886,7 +3886,7 @@
 Version 1.6.0beta07 [January 28, 2012]
   Eliminated Intel icc/icl compiler warnings. The Intel (GCC derived)
     compiler issues slightly different warnings from those issued by the
-    current vesions of GCC. This eliminates those warnings by
+    current versions of GCC. This eliminates those warnings by
     adding/removing casts and small code rewrites.
   Updated configure.ac from autoupdate: added --enable-werror option.
     Also some layout regularization and removal of introduced tab characters
@@ -6103,6 +6103,12 @@
   Added makefiles for AddressSanitizer-enabled builds.
   Cleaned up various makefiles.
 
+Version 1.6.38 [September 14, 2022]
+  Added configurations and scripts for continuous integration.
+  Fixed various errors in the handling of tRNS, hIST and eXIf.
+  Implemented many stability improvements across all platforms.
+  Updated the internal documentation.
+
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
 Subscription is required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6451fcf..8652564 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,7 @@
 # CMakeLists.txt
 
-# Copyright (C) 2018 Cosmin Truta
-# Copyright (C) 2007,2009-2018 Glenn Randers-Pehrson
+# Copyright (c) 2018-2022 Cosmin Truta
+# Copyright (c) 2007,2009-2018 Glenn Randers-Pehrson
 # Written by Christian Ehrlicher, 2007
 # Revised by Roger Lowman, 2009-2010
 # Revised by Clifford Yapp, 2011-2012,2017
@@ -10,9 +10,15 @@
 # Revised by Sam Serrels, 2017
 # Revised by Vadim Barkov, 2017
 # Revised by Vicky Pfau, 2018
-# Revised by Cameron Cawley, 2018
-# Revised by Cosmin Truta, 2018
+# Revised by Cameron Cawley, 2018,2021
 # Revised by Kyle Bentley, 2018
+# Revised by David Callu, 2020
+# Revised by Steve Robinson, 2020
+# Revised by Simon Hausmann, 2020
+# Revised by Alex Gaynor, 2020
+# Revised by Owen Rudge, 2020
+# Revised by Gleb Mazovetskiy, 2021
+# Revised by Christopher Sean Morrison, 2022
 
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -26,36 +32,42 @@
 
 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 37)
+set(PNGLIB_REVISION 38)
+set(PNGLIB_SUBREVISION 0)
+#set(PNGLIB_SUBREVISION "git")
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
-set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
+set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_REVISION})
+set(PNGLIB_SHARED_SOVERSION ${PNGLIB_MAJOR}${PNGLIB_MINOR})
+set(PNGLIB_SHARED_VERSION ${PNGLIB_SHARED_SOVERSION}.${PNGLIB_REVISION}.${PNGLIB_SUBREVISION})
 
 include(GNUInstallDirs)
 
-# needed packages
-
-# Allow users to specify location of Zlib.
+# Allow users to specify location of zlib.
 # Useful if zlib is being built alongside this as a sub-project.
 option(PNG_BUILD_ZLIB "Custom zlib Location, else find_package is used" OFF)
 
 if(NOT PNG_BUILD_ZLIB)
   find_package(ZLIB REQUIRED)
-  include_directories(${ZLIB_INCLUDE_DIR})
+  include_directories(${ZLIB_INCLUDE_DIRS})
 endif()
 
-if(UNIX AND NOT APPLE AND NOT BEOS AND NOT HAIKU)
+if(UNIX AND NOT APPLE AND NOT BEOS AND NOT HAIKU AND NOT EMSCRIPTEN)
   find_library(M_LIBRARY m)
+  if(NOT M_LIBRARY)
+    set(M_LIBRARY "")
+  endif()
 else()
-  # libm is not needed and/or not available
+  # libm is not needed and/or not available.
   set(M_LIBRARY "")
 endif()
 
-# COMMAND LINE OPTIONS
+# Public CMake configuration variables.
 option(PNG_SHARED "Build shared lib" ON)
 option(PNG_STATIC "Build static lib" ON)
-option(PNG_TESTS  "Build libpng tests" ON)
+option(PNG_EXECUTABLES "Build libpng executables" ON)
+option(PNG_TESTS "Build libpng tests" ON)
 
-# Many more configuration options could be added here
+# Many more configuration options could be added here.
 option(PNG_FRAMEWORK "Build OS X framework" OFF)
 option(PNG_DEBUG "Build with debug output" OFF)
 option(PNG_HARDWARE_OPTIMIZATIONS "Enable hardware optimizations" ON)
@@ -63,29 +75,43 @@
 set(PNG_PREFIX "" CACHE STRING "Prefix to add to the API function names")
 set(DFA_XTRA "" CACHE FILEPATH "File containing extra configuration settings")
 
+# CMake currently sets CMAKE_SYSTEM_PROCESSOR to one of x86_64 or arm64 on macOS,
+# based upon the OS architecture, not the target architecture. As such, we need
+# to check CMAKE_OSX_ARCHITECTURES to identify which hardware-specific flags to
+# enable. Note that this will fail if you attempt to build a universal binary in
+# a single CMake invocation.
+if (APPLE AND CMAKE_OSX_ARCHITECTURES)
+  set(TARGET_ARCH ${CMAKE_OSX_ARCHITECTURES})
+else()
+  set(TARGET_ARCH ${CMAKE_SYSTEM_PROCESSOR})
+endif()
+
 if(PNG_HARDWARE_OPTIMIZATIONS)
 
-# set definitions and sources for arm
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^arm" OR
-  CMAKE_SYSTEM_PROCESSOR MATCHES "^aarch64")
-  set(PNG_ARM_NEON_POSSIBLE_VALUES check on off)
-  set(PNG_ARM_NEON "check" CACHE STRING "Enable ARM NEON optimizations:
-     check: (default) use internal checking code;
-     off: disable the optimizations;
-     on: turn on unconditionally.")
-  set_property(CACHE PNG_ARM_NEON PROPERTY STRINGS
-     ${PNG_ARM_NEON_POSSIBLE_VALUES})
+# Set definitions and sources for ARM.
+if(TARGET_ARCH MATCHES "^arm" OR
+   TARGET_ARCH MATCHES "^aarch64")
+  if(TARGET_ARCH MATCHES "^arm64" OR
+     TARGET_ARCH MATCHES "^aarch64")
+    set(PNG_ARM_NEON_POSSIBLE_VALUES on off)
+    set(PNG_ARM_NEON "on"
+        CACHE STRING "Enable ARM NEON optimizations: on|off; on is default")
+  else()
+    set(PNG_ARM_NEON_POSSIBLE_VALUES check on off)
+    set(PNG_ARM_NEON "check"
+        CACHE STRING "Enable ARM NEON optimizations: check|on|off; check is default")
+  endif()
+  set_property(CACHE PNG_ARM_NEON
+               PROPERTY STRINGS ${PNG_ARM_NEON_POSSIBLE_VALUES})
   list(FIND PNG_ARM_NEON_POSSIBLE_VALUES ${PNG_ARM_NEON} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_ARM_NEON must be one of [${PNG_ARM_NEON_POSSIBLE_VALUES}]")
+    message(FATAL_ERROR "PNG_ARM_NEON must be one of [${PNG_ARM_NEON_POSSIBLE_VALUES}]")
   elseif(NOT ${PNG_ARM_NEON} STREQUAL "off")
     set(libpng_arm_sources
-      arm/arm_init.c
-      arm/filter_neon.S
-      arm/filter_neon_intrinsics.c
-      arm/palette_neon_intrinsics.c)
-
+        arm/arm_init.c
+        arm/filter_neon.S
+        arm/filter_neon_intrinsics.c
+        arm/palette_neon_intrinsics.c)
     if(${PNG_ARM_NEON} STREQUAL "on")
       add_definitions(-DPNG_ARM_NEON_OPT=2)
     elseif(${PNG_ARM_NEON} STREQUAL "check")
@@ -96,22 +122,21 @@
   endif()
 endif()
 
-# set definitions and sources for powerpc
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^powerpc*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^ppc64*")
+# Set definitions and sources for PowerPC.
+if(TARGET_ARCH MATCHES "^powerpc*" OR
+   TARGET_ARCH MATCHES "^ppc64*")
   set(PNG_POWERPC_VSX_POSSIBLE_VALUES on off)
-  set(PNG_POWERPC_VSX "on" CACHE STRING "Enable POWERPC VSX optimizations:
-     off: disable the optimizations.")
-  set_property(CACHE PNG_POWERPC_VSX PROPERTY STRINGS
-     ${PNG_POWERPC_VSX_POSSIBLE_VALUES})
+  set(PNG_POWERPC_VSX "on"
+      CACHE STRING "Enable POWERPC VSX optimizations: on|off; on is default")
+  set_property(CACHE PNG_POWERPC_VSX
+               PROPERTY STRINGS ${PNG_POWERPC_VSX_POSSIBLE_VALUES})
   list(FIND PNG_POWERPC_VSX_POSSIBLE_VALUES ${PNG_POWERPC_VSX} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_POWERPC_VSX must be one of [${PNG_POWERPC_VSX_POSSIBLE_VALUES}]")
+    message(FATAL_ERROR "PNG_POWERPC_VSX must be one of [${PNG_POWERPC_VSX_POSSIBLE_VALUES}]")
   elseif(NOT ${PNG_POWERPC_VSX} STREQUAL "off")
     set(libpng_powerpc_sources
-      powerpc/powerpc_init.c
-      powerpc/filter_vsx_intrinsics.c)
+        powerpc/powerpc_init.c
+        powerpc/filter_vsx_intrinsics.c)
     if(${PNG_POWERPC_VSX} STREQUAL "on")
       add_definitions(-DPNG_POWERPC_VSX_OPT=2)
     endif()
@@ -120,22 +145,21 @@
   endif()
 endif()
 
-# set definitions and sources for intel
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^i?86" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^x86_64*")
+# Set definitions and sources for Intel.
+if(TARGET_ARCH MATCHES "^i?86" OR
+   TARGET_ARCH MATCHES "^x86_64*")
   set(PNG_INTEL_SSE_POSSIBLE_VALUES on off)
-  set(PNG_INTEL_SSE "on" CACHE STRING "Enable INTEL_SSE optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_INTEL_SSE PROPERTY STRINGS
-     ${PNG_INTEL_SSE_POSSIBLE_VALUES})
+  set(PNG_INTEL_SSE "on"
+      CACHE STRING "Enable INTEL_SSE optimizations: on|off; on is default")
+  set_property(CACHE PNG_INTEL_SSE
+               PROPERTY STRINGS ${PNG_INTEL_SSE_POSSIBLE_VALUES})
   list(FIND PNG_INTEL_SSE_POSSIBLE_VALUES ${PNG_INTEL_SSE} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_INTEL_SSE must be one of [${PNG_INTEL_SSE_POSSIBLE_VALUES}]")
+    message(FATAL_ERROR "PNG_INTEL_SSE must be one of [${PNG_INTEL_SSE_POSSIBLE_VALUES}]")
   elseif(NOT ${PNG_INTEL_SSE} STREQUAL "off")
     set(libpng_intel_sources
-      intel/intel_init.c
-      intel/filter_sse2_intrinsics.c)
+        intel/intel_init.c
+        intel/filter_sse2_intrinsics.c)
     if(${PNG_INTEL_SSE} STREQUAL "on")
       add_definitions(-DPNG_INTEL_SSE_OPT=1)
     endif()
@@ -144,22 +168,21 @@
   endif()
 endif()
 
-# set definitions and sources for MIPS
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "mipsel*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "mips64el*")
+# Set definitions and sources for MIPS.
+if(TARGET_ARCH MATCHES "mipsel*" OR
+   TARGET_ARCH MATCHES "mips64el*")
   set(PNG_MIPS_MSA_POSSIBLE_VALUES on off)
-  set(PNG_MIPS_MSA "on" CACHE STRING "Enable MIPS_MSA optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_MIPS_MSA PROPERTY STRINGS
-     ${PNG_MIPS_MSA_POSSIBLE_VALUES})
+  set(PNG_MIPS_MSA "on"
+      CACHE STRING "Enable MIPS_MSA optimizations: on|off; on is default")
+  set_property(CACHE PNG_MIPS_MSA
+               PROPERTY STRINGS ${PNG_MIPS_MSA_POSSIBLE_VALUES})
   list(FIND PNG_MIPS_MSA_POSSIBLE_VALUES ${PNG_MIPS_MSA} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_MIPS_MSA must be one of [${PNG_MIPS_MSA_POSSIBLE_VALUES}]")
+    message(FATAL_ERROR "PNG_MIPS_MSA must be one of [${PNG_MIPS_MSA_POSSIBLE_VALUES}]")
   elseif(NOT ${PNG_MIPS_MSA} STREQUAL "off")
     set(libpng_mips_sources
-      mips/mips_init.c
-      mips/filter_msa_intrinsics.c)
+        mips/mips_init.c
+        mips/filter_msa_intrinsics.c)
     if(${PNG_MIPS_MSA} STREQUAL "on")
       add_definitions(-DPNG_MIPS_MSA_OPT=2)
     endif()
@@ -170,43 +193,44 @@
 
 else(PNG_HARDWARE_OPTIMIZATIONS)
 
-# set definitions and sources for arm
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^arm" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^aarch64")
+# Set definitions and sources for ARM.
+if(TARGET_ARCH MATCHES "^arm" OR
+   TARGET_ARCH MATCHES "^aarch64")
   add_definitions(-DPNG_ARM_NEON_OPT=0)
 endif()
 
-# set definitions and sources for powerpc
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^powerpc*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^ppc64*")
+# Set definitions and sources for PowerPC.
+if(TARGET_ARCH MATCHES "^powerpc*" OR
+   TARGET_ARCH MATCHES "^ppc64*")
   add_definitions(-DPNG_POWERPC_VSX_OPT=0)
 endif()
 
-# set definitions and sources for intel
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^i?86" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^x86_64*")
+# Set definitions and sources for Intel.
+if(TARGET_ARCH MATCHES "^i?86" OR
+   TARGET_ARCH MATCHES "^x86_64*")
   add_definitions(-DPNG_INTEL_SSE_OPT=0)
 endif()
 
-# set definitions and sources for MIPS
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "mipsel*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "mips64el*")
+# Set definitions and sources for MIPS.
+if(TARGET_ARCH MATCHES "mipsel*" OR
+   TARGET_ARCH MATCHES "mips64el*")
   add_definitions(-DPNG_MIPS_MSA_OPT=0)
 endif()
 
 endif(PNG_HARDWARE_OPTIMIZATIONS)
 
-# SET LIBNAME
+# Set PNG_LIB_NAME.
 set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})
 
-# to distinguish between debug and release lib
+# Distinguish between debug and release builds.
 set(CMAKE_DEBUG_POSTFIX "d")
 
 include(CheckCSourceCompiles)
 option(ld-version-script "Enable linker version script" ON)
-if(ld-version-script AND NOT APPLE)
+if(ld-version-script AND NOT ANDROID AND NOT APPLE)
   # Check if LD supports linker scripts.
-  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "VERS_1 {
+  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "
+VERS_1 {
         global: sym;
         local: *;
 };
@@ -272,15 +296,29 @@
 
 include_directories(${CMAKE_CURRENT_BINARY_DIR})
 
-if(NOT AWK OR ANDROID)
+if(NOT AWK OR ANDROID OR IOS)
   # No awk available to generate sources; use pre-built pnglibconf.h
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
                  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
   add_custom_target(genfiles) # Dummy
 else()
-  include(CMakeParseArguments)
-  # Generate .chk from .out with awk
+  # Copy the awk scripts, converting their line endings to Unix (LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/checksym.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/dfn.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/dfn.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+
+  # Generate .chk from .out with awk:
   # generate_chk(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
+  include(CMakeParseArguments)
   function(generate_chk)
     set(options)
     set(oneValueArgs INPUT OUTPUT)
@@ -345,25 +383,33 @@
   endfunction()
 
   # Copy file
-  function(generate_copy source destination)
-    add_custom_command(OUTPUT "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E remove "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E copy "${source}"
-                                                          "${destination}"
-                       DEPENDS "${source}")
+  # generate_copy(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
+  function(generate_copy)
+    set(options)
+    set(oneValueArgs INPUT OUTPUT)
+    set(multiValueArgs DEPENDS)
+    cmake_parse_arguments(_GCO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    add_custom_command(OUTPUT "${_GCO_OUTPUT}"
+                       COMMAND "${CMAKE_COMMAND}"
+                               -E remove "${_GCO_OUTPUT}"
+                       COMMAND "${CMAKE_COMMAND}"
+                               -E copy "${_GCO_INPUT}" "${_GCO_OUTPUT}"
+                       DEPENDS "${source}" ${_GCO_DEPENDS})
   endfunction()
 
   # Generate scripts/pnglibconf.h
   generate_source(OUTPUT "scripts/pnglibconf.c"
                   DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
+                          "${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk"
                           "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
+  add_custom_target(scripts_pnglibconf_c DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c")
 
   # Generate pnglibconf.c
   generate_source(OUTPUT "pnglibconf.c"
                   DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
+                          "${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk"
                           "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
+  add_custom_target(pnglibconf_c DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c")
 
   if(PNG_PREFIX)
     set(PNGLIBCONF_H_EXTRA_DEPENDS
@@ -374,58 +420,72 @@
   endif()
 
   generate_out(INPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
+               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
+               DEPENDS pnglibconf_c)
+  add_custom_target(pnglibconf_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
 
   # Generate pnglibconf.h
   generate_source(OUTPUT "pnglibconf.h"
-                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
+                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out
                           ${PNGLIBCONF_H_EXTRA_DEPENDS})
+  add_custom_target(pnglibconf_h DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/intprefix.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(scripts_intprefix_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/prefix.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
+                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out)
+  add_custom_target(scripts_prefix_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out")
 
   # Generate pngprefix.h
   generate_source(OUTPUT "pngprefix.h"
                   DEPENDS ${PNGPREFIX_H_EXTRA_DEPENDS})
+  add_custom_target(pngprefix_h DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/sym.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(scripts_sym_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt")
+  add_custom_target(scripts_symbols_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/vers.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(scripts_vers_out DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
 
   generate_chk(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk"
+               DEPENDS scripts_symbols_out
+                       "${CMAKE_CURRENT_BINARY_DIR}/scripts/checksym.awk"
                        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.def")
 
-  add_custom_target(symbol-check DEPENDS
-                    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
+  add_custom_target(scripts_symbols_chk
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
 
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
+  generate_copy(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
+                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
+                DEPENDS scripts_sym_out)
+  generate_copy(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
+                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
+                DEPENDS scripts_vers_out)
 
-  add_custom_target(genvers DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-  add_custom_target(gensym DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
+  add_custom_target(genvers
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
+  add_custom_target(gensym
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
 
   add_custom_target("genprebuilt"
                     COMMAND "${CMAKE_COMMAND}"
@@ -433,84 +493,81 @@
                             -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
                     WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
 
-  # A single target handles generation of all generated files.  If
-  # they are depended upon separately by multiple targets, this
-  # confuses parallel make (it would require a separate top-level
-  # target for each file to track the dependencies properly).
-  add_custom_target(genfiles DEPENDS
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
-endif(NOT AWK OR ANDROID)
+  # A single target handles generation of all generated files.
+  add_custom_target(genfiles
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym" gensym
+                            "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers" genvers
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c" pnglibconf_c
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h" pngprefix_h
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out" scripts_intprefix_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c" scripts_pnglibconf_c
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out" scripts_prefix_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out" scripts_sym_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk" scripts_symbols_chk
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out" scripts_symbols_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out" scripts_vers_out)
+endif(NOT AWK OR ANDROID OR IOS)
 
-# OUR SOURCES
+# List the source code files.
 set(libpng_public_hdrs
-  png.h
-  pngconf.h
-  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
+    png.h
+    pngconf.h
+    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
 )
 set(libpng_private_hdrs
-  pngpriv.h
-  pngdebug.h
-  pnginfo.h
-  pngstruct.h
+    pngpriv.h
+    pngdebug.h
+    pnginfo.h
+    pngstruct.h
 )
-if(AWK AND NOT ANDROID)
+if(AWK AND NOT ANDROID AND NOT IOS)
   list(APPEND libpng_private_hdrs "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
 endif()
 set(libpng_sources
-  ${libpng_public_hdrs}
-  ${libpng_private_hdrs}
-  png.c
-  pngerror.c
-  pngget.c
-  pngmem.c
-  pngpread.c
-  pngread.c
-  pngrio.c
-  pngrtran.c
-  pngrutil.c
-  pngset.c
-  pngtrans.c
-  pngwio.c
-  pngwrite.c
-  pngwtran.c
-  pngwutil.c
-  ${libpng_arm_sources}
-  ${libpng_intel_sources}
-  ${libpng_mips_sources}
-  ${libpng_powerpc_sources}
+    ${libpng_public_hdrs}
+    ${libpng_private_hdrs}
+    png.c
+    pngerror.c
+    pngget.c
+    pngmem.c
+    pngpread.c
+    pngread.c
+    pngrio.c
+    pngrtran.c
+    pngrutil.c
+    pngset.c
+    pngtrans.c
+    pngwio.c
+    pngwrite.c
+    pngwtran.c
+    pngwutil.c
+    ${libpng_arm_sources}
+    ${libpng_intel_sources}
+    ${libpng_mips_sources}
+    ${libpng_powerpc_sources}
 )
 set(pngtest_sources
-  pngtest.c
+    pngtest.c
 )
 set(pngvalid_sources
-  contrib/libtests/pngvalid.c
+    contrib/libtests/pngvalid.c
 )
 set(pngstest_sources
-  contrib/libtests/pngstest.c
+    contrib/libtests/pngstest.c
 )
 set(pngunknown_sources
-  contrib/libtests/pngunknown.c
+    contrib/libtests/pngunknown.c
 )
 set(pngimage_sources
-  contrib/libtests/pngimage.c
+    contrib/libtests/pngimage.c
 )
 set(pngfix_sources
-  contrib/tools/pngfix.c
+    contrib/tools/pngfix.c
 )
 set(png_fix_itxt_sources
-  contrib/tools/png-fix-itxt.c
+    contrib/tools/png-fix-itxt.c
 )
 
 if(MSVC)
@@ -521,8 +578,8 @@
   add_definitions(-DPNG_DEBUG)
 endif()
 
-# NOW BUILD OUR TARGET
-include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
+# Now build our target.
+include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIRS})
 
 unset(PNG_LIB_TARGETS)
 
@@ -532,19 +589,19 @@
   set_target_properties(png PROPERTIES OUTPUT_NAME ${PNG_LIB_NAME})
   add_dependencies(png genfiles)
   if(MSVC)
-    # msvc does not append 'lib' - do it here to have consistent name
+    # MVC does not append 'lib'. Do it here, to have consistent name.
     set_target_properties(png PROPERTIES PREFIX "lib")
     set_target_properties(png PROPERTIES IMPORT_PREFIX "lib")
   endif()
-  target_link_libraries(png ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(png ${ZLIB_LIBRARIES} ${M_LIBRARY})
 
   if(UNIX AND AWK)
     if(HAVE_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
+      set_target_properties(png PROPERTIES
+                            LINK_FLAGS "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
     elseif(HAVE_SOLARIS_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
+      set_target_properties(png PROPERTIES
+                            LINK_FLAGS "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
     endif()
   endif()
 endif()
@@ -555,23 +612,23 @@
   add_library(png_static STATIC ${libpng_sources})
   add_dependencies(png_static genfiles)
   # MSVC doesn't use a different file extension for shared vs. static
-  # libs.  We are able to change OUTPUT_NAME to remove the _static
+  # libs. We are able to change OUTPUT_NAME to remove the _static
   # for all other platforms.
   if(NOT MSVC)
     set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}"
-      CLEAN_DIRECT_OUTPUT 1)
+                          OUTPUT_NAME "${PNG_LIB_NAME}"
+                          CLEAN_DIRECT_OUTPUT 1)
   else()
     set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}_static"
-      CLEAN_DIRECT_OUTPUT 1)
+                          OUTPUT_NAME "${PNG_LIB_NAME}_static"
+                          CLEAN_DIRECT_OUTPUT 1)
   endif()
   list(APPEND PNG_LIB_TARGETS png_static)
   if(MSVC)
-    # msvc does not append 'lib' - do it here to have consistent name
+    # MSVC does not append 'lib'. Do it here, to have consistent name.
     set_target_properties(png_static PROPERTIES PREFIX "lib")
   endif()
-  target_link_libraries(png_static ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(png_static ${ZLIB_LIBRARIES} ${M_LIBRARY})
 endif()
 
 if(PNG_FRAMEWORK)
@@ -580,26 +637,26 @@
   add_dependencies(png_framework genfiles)
   list(APPEND PNG_LIB_TARGETS png_framework)
   set_target_properties(png_framework PROPERTIES
-    FRAMEWORK TRUE
-    FRAMEWORK_VERSION ${PNGLIB_VERSION}
-    MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
-    MACOSX_FRAMEWORK_BUNDLE_VERSION ${PNGLIB_VERSION}
-    MACOSX_FRAMEWORK_IDENTIFIER org.libpng.libpng
-    XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
-    PUBLIC_HEADER "${libpng_public_hdrs}"
-    OUTPUT_NAME png)
-  target_link_libraries(png_framework ${ZLIB_LIBRARY} ${M_LIBRARY})
+                        FRAMEWORK TRUE
+                        FRAMEWORK_VERSION ${PNGLIB_VERSION}
+                        MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
+                        MACOSX_FRAMEWORK_BUNDLE_VERSION ${PNGLIB_VERSION}
+                        MACOSX_FRAMEWORK_IDENTIFIER org.libpng.libpng
+                        XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
+                        PUBLIC_HEADER "${libpng_public_hdrs}"
+                        OUTPUT_NAME png)
+  target_link_libraries(png_framework ${ZLIB_LIBRARIES} ${M_LIBRARY})
 endif()
 
 if(NOT PNG_LIB_TARGETS)
-  message(SEND_ERROR
-    "No library variant selected to build. "
-    "Please enable at least one of the following options: "
-    "PNG_STATIC, PNG_SHARED, PNG_FRAMEWORK")
+  message(SEND_ERROR "No library variant selected to build. "
+                     "Please enable at least one of the following options: "
+                     "PNG_STATIC, PNG_SHARED, PNG_FRAMEWORK")
 endif()
 
 if(PNG_SHARED AND WIN32)
-  set_target_properties(png PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+  set_target_properties(png PROPERTIES
+                        DEFINE_SYMBOL PNG_BUILD_DLL)
 endif()
 
 function(png_add_test)
@@ -619,12 +676,13 @@
   set(TEST_FILES "${_PAT_FILES}")
 
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/test.cmake.in"
-                 "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake" @ONLY)
+                 "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake"
+                 @ONLY)
   add_test(NAME "${_PAT_NAME}"
            COMMAND "${CMAKE_COMMAND}"
-           "-DLIBPNG=$<TARGET_FILE:png>"
-           "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
-           -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
+                   "-DLIBPNG=$<TARGET_FILE:png>"
+                   "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
+                   -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
 endfunction()
 
 if(PNG_TESTS AND PNG_SHARED)
@@ -640,39 +698,55 @@
   add_executable(pngtest ${pngtest_sources})
   target_link_libraries(pngtest png)
 
-  png_add_test(NAME pngtest COMMAND pngtest FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngtest
+               COMMAND pngtest
+               FILES "${PNGTEST_PNG}")
 
   add_executable(pngvalid ${pngvalid_sources})
   target_link_libraries(pngvalid png)
 
   png_add_test(NAME pngvalid-gamma-16-to-8
-               COMMAND pngvalid OPTIONS --gamma-16-to-8)
+               COMMAND pngvalid
+               OPTIONS --gamma-16-to-8)
   png_add_test(NAME pngvalid-gamma-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode)
+               COMMAND pngvalid
+               OPTIONS --gamma-alpha-mode)
   png_add_test(NAME pngvalid-gamma-background
-               COMMAND pngvalid OPTIONS --gamma-background)
+               COMMAND pngvalid
+               OPTIONS --gamma-background)
   png_add_test(NAME pngvalid-gamma-expand16-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-alpha-mode --expand16)
   png_add_test(NAME pngvalid-gamma-expand16-background
-               COMMAND pngvalid OPTIONS --gamma-background --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-background --expand16)
   png_add_test(NAME pngvalid-gamma-expand16-transform
-               COMMAND pngvalid OPTIONS --gamma-transform --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-transform --expand16)
   png_add_test(NAME pngvalid-gamma-sbit
-               COMMAND pngvalid OPTIONS --gamma-sbit)
+               COMMAND pngvalid
+               OPTIONS --gamma-sbit)
   png_add_test(NAME pngvalid-gamma-threshold
-               COMMAND pngvalid OPTIONS --gamma-threshold)
+               COMMAND pngvalid
+               OPTIONS --gamma-threshold)
   png_add_test(NAME pngvalid-gamma-transform
-               COMMAND pngvalid OPTIONS --gamma-transform)
+               COMMAND pngvalid
+               OPTIONS --gamma-transform)
   png_add_test(NAME pngvalid-progressive-interlace-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read --interlace)
+               COMMAND pngvalid
+               OPTIONS --standard --progressive-read --interlace)
   png_add_test(NAME pngvalid-progressive-size
-               COMMAND pngvalid OPTIONS --size --progressive-read)
+               COMMAND pngvalid
+               OPTIONS --size --progressive-read)
   png_add_test(NAME pngvalid-progressive-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read)
+               COMMAND pngvalid
+               OPTIONS --standard --progressive-read)
   png_add_test(NAME pngvalid-standard
-               COMMAND pngvalid OPTIONS --standard)
+               COMMAND pngvalid
+               OPTIONS --standard)
   png_add_test(NAME pngvalid-transform
-               COMMAND pngvalid OPTIONS --transform)
+               COMMAND pngvalid
+               OPTIONS --transform)
 
   add_executable(pngstest ${pngstest_sources})
   target_link_libraries(pngstest png)
@@ -732,38 +806,62 @@
   add_executable(pngunknown ${pngunknown_sources})
   target_link_libraries(pngunknown png)
 
-  png_add_test(NAME pngunknown-discard COMMAND pngunknown OPTIONS --strict default=discard FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-IDAT COMMAND pngunknown OPTIONS --strict default=discard IDAT=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-if-safe COMMAND pngunknown OPTIONS --strict default=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sAPI COMMAND pngunknown OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-save COMMAND pngunknown OPTIONS --strict default=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sTER COMMAND pngunknown OPTIONS --strict sTER=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-vpAg COMMAND pngunknown OPTIONS --strict vpAg=if-safe FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-discard
+               COMMAND pngunknown
+               OPTIONS --strict default=discard
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-IDAT
+               COMMAND pngunknown
+               OPTIONS --strict default=discard IDAT=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-if-safe
+               COMMAND pngunknown
+               OPTIONS --strict default=if-safe
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-sAPI
+               COMMAND pngunknown
+               OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-save
+               COMMAND pngunknown
+               OPTIONS --strict default=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-sTER
+               COMMAND pngunknown
+               OPTIONS --strict sTER=if-safe
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-vpAg
+               COMMAND pngunknown
+               OPTIONS --strict vpAg=if-safe
+               FILES "${PNGTEST_PNG}")
 
   add_executable(pngimage ${pngimage_sources})
   target_link_libraries(pngimage png)
 
-  png_add_test(NAME pngimage-quick COMMAND pngimage OPTIONS --list-combos --log FILES ${PNGSUITE_PNGS})
-  png_add_test(NAME pngimage-full COMMAND pngimage OPTIONS --exhaustive --list-combos --log FILES ${PNGSUITE_PNGS})
+  png_add_test(NAME pngimage-quick
+               COMMAND pngimage
+               OPTIONS --list-combos --log
+               FILES ${PNGSUITE_PNGS})
+  png_add_test(NAME pngimage-full
+               COMMAND pngimage
+               OPTIONS --exhaustive --list-combos --log
+               FILES ${PNGSUITE_PNGS})
 endif()
 
-if(PNG_SHARED)
+if(PNG_SHARED AND PNG_EXECUTABLES)
   add_executable(pngfix ${pngfix_sources})
   target_link_libraries(pngfix png)
   set(PNG_BIN_TARGETS pngfix)
 
   add_executable(png-fix-itxt ${png_fix_itxt_sources})
-  target_link_libraries(png-fix-itxt ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(png-fix-itxt ${ZLIB_LIBRARIES} ${M_LIBRARY})
   list(APPEND PNG_BIN_TARGETS png-fix-itxt)
 endif()
 
-# Set a variable with CMake code which:
-# Creates a symlink from src to dest (if possible) or alternatively
-# copies if different.
+# Creates a symlink from src to dest (if possible), or, alternatively,
+# copies src to dest if different.
 include(CMakeParseArguments)
-
 function(create_symlink DEST_FILE)
-
   cmake_parse_arguments(S "" "FILE;TARGET" "" ${ARGN})
 
   if(NOT S_TARGET AND NOT S_FILE)
@@ -771,55 +869,69 @@
   endif()
 
   if(S_TARGET AND S_FILE)
-    message(FATAL_ERROR "create_symlink: Both source file ${S_FILE} and build target ${S_TARGET} arguments are present; can only have one.")
+    message(FATAL_ERROR "create_symlink: "
+                        "Both source file ${S_FILE} and build target ${S_TARGET} arguments are present; "
+                        "can only have one")
   endif()
 
   if(S_FILE)
     # If we don't need to symlink something that's coming from a build target,
     # we can go ahead and symlink/copy at configure time.
     if(CMAKE_HOST_WIN32 AND NOT CYGWIN)
-      execute_process(
-        COMMAND "${CMAKE_COMMAND}" -E copy_if_different ${S_FILE} ${DEST_FILE}
-        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
+      execute_process(COMMAND "${CMAKE_COMMAND}"
+                              -E copy_if_different
+                              ${S_FILE} ${DEST_FILE}
+                      WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     else()
-      execute_process(
-        COMMAND ${CMAKE_COMMAND} -E create_symlink ${S_FILE} ${DEST_FILE}
-        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
+      execute_process(COMMAND "${CMAKE_COMMAND}"
+                              -E create_symlink
+                              ${S_FILE} ${DEST_FILE}
+                      WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     endif()
   endif()
 
   if(S_TARGET)
-    # We need to use generator expressions, which can be a bit tricky, so for
-    # simplicity make the symlink a POST_BUILD step and use the TARGET
+    # We need to use generator expressions, which can be a bit tricky.
+    # For simplicity, make the symlink a POST_BUILD step, and use the TARGET
     # signature of add_custom_command.
     if(CMAKE_HOST_WIN32 AND NOT CYGWIN)
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-        COMMAND "${CMAKE_COMMAND}" -E copy_if_different $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
+      add_custom_command(TARGET ${S_TARGET}
+                         POST_BUILD
+                         COMMAND "${CMAKE_COMMAND}"
+                                 -E copy_if_different
+                                 $<TARGET_LINKER_FILE_NAME:${S_TARGET}>
+                                 $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
     else()
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-        COMMAND "${CMAKE_COMMAND}" -E create_symlink $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
+      add_custom_command(TARGET ${S_TARGET}
+                         POST_BUILD
+                         COMMAND "${CMAKE_COMMAND}"
+                                 -E create_symlink
+                                 $<TARGET_LINKER_FILE_NAME:${S_TARGET}>
+                                 $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
     endif()
   endif()
-
 endfunction()
 
 # Create source generation scripts.
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genchk.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake @ONLY)
+               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake
+               @ONLY)
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genout.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake @ONLY)
+               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake
+               @ONLY)
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/gensrc.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake @ONLY)
+               ${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake
+               @ONLY)
 
 # libpng is a library so default to 'lib'
 if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
   set(CMAKE_INSTALL_LIBDIR lib)
 endif()
 
-# CREATE PKGCONFIG FILES
+# Create pkgconfig files.
 # We use the same files like ./configure, so we have to set its vars.
-# Only do this on Windows for Cygwin - the files don't make much sense outside
-# of a UNIX look-alike.
+# Only do this on Windows for Cygwin - the files don't make much sense
+# outside of a UNIX look-alike.
 if(NOT WIN32 OR CYGWIN OR MINGW)
   set(prefix      ${CMAKE_INSTALL_PREFIX})
   set(exec_prefix ${CMAKE_INSTALL_PREFIX})
@@ -827,24 +939,24 @@
   set(includedir  ${CMAKE_INSTALL_FULL_INCLUDEDIR})
   set(LIBS        "-lz -lm")
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
-    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
+                 ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
+                 @ONLY)
   create_symlink(libpng.pc FILE ${PNGLIB_NAME}.pc)
-
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
-    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
+                 ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+                 @ONLY)
   create_symlink(libpng-config FILE ${PNGLIB_NAME}-config)
 endif()
 
-# SET UP LINKS
+# Set up links.
 if(PNG_SHARED)
   set_target_properties(png PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.37
-    VERSION 16.${PNGLIB_RELEASE}.0
-    SOVERSION 16
+    VERSION ${PNGLIB_SHARED_VERSION}
+    SOVERSION ${PNGLIB_SHARED_SOVERSION}
     CLEAN_DIRECT_OUTPUT 1)
 endif()
 
-# INSTALL
+# Install.
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
   install(TARGETS ${PNG_LIB_TARGETS}
           EXPORT libpng
@@ -878,13 +990,17 @@
 endif()
 
 if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL)
-  install(FILES ${libpng_public_hdrs} DESTINATION include)
-  install(FILES ${libpng_public_hdrs} DESTINATION include/${PNGLIB_NAME})
+  install(FILES ${libpng_public_hdrs}
+          DESTINATION include)
+  install(FILES ${libpng_public_hdrs}
+          DESTINATION include/${PNGLIB_NAME})
 endif()
 if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL)
   if(NOT WIN32 OR CYGWIN OR MINGW)
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config DESTINATION bin)
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config DESTINATION bin)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
+            DESTINATION bin)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+            DESTINATION bin)
   endif()
 endif()
 
@@ -894,38 +1010,31 @@
 endif()
 
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL)
-  # Install man pages
-  if(NOT PNG_MAN_DIR)
-    set(PNG_MAN_DIR "share/man")
-  endif()
-  install(FILES libpng.3 libpngpf.3 DESTINATION ${PNG_MAN_DIR}/man3)
-  install(FILES png.5 DESTINATION ${PNG_MAN_DIR}/man5)
-  # Install pkg-config files
+  # Install the man pages.
+  install(FILES libpng.3 libpngpf.3
+          DESTINATION ${CMAKE_INSTALL_MANDIR}/man3)
+  install(FILES png.5
+          DESTINATION ${CMAKE_INSTALL_MANDIR}/man5)
+  # Install the pkg-config files.
   if(NOT CMAKE_HOST_WIN32 OR CYGWIN OR MINGW)
     install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc
             DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
     install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
-            DESTINATION bin)
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
     install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
             DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
     install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
-            DESTINATION bin)
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
   endif()
 endif()
 
 # Create an export file that CMake users can include() to import our targets.
 if(NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL)
-  install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
+  install(EXPORT libpng
+          DESTINATION lib/libpng
+          FILE lib${PNG_LIB_NAME}.cmake)
 endif()
 
-# what's with libpng-manual.txt and all the extra files?
-
-# UNINSTALL
-# do we need this?
-
-# DIST
-# do we need this?
-
-# to create msvc import lib for mingw compiled shared lib
+# TODO: Create MSVC import lib for MinGW-compiled shared lib.
 # pexports libpng.dll > libpng.def
 # lib /def:libpng.def /machine:x86
diff --git a/INSTALL b/INSTALL
index 4c17022..d3aaa28 100644
--- a/INSTALL
+++ b/INSTALL
@@ -128,16 +128,18 @@
           README
           *.h, *.c  => libpng source files
           CMakeLists.txt    =>  "cmake" script
+          ci
+             ci_*.sh
           configuration files:
              configure.ac, configure, Makefile.am, Makefile.in,
              autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
              libpng-config.in, aclocal.m4, config.h.in, config.sub,
-             depcomp, install-sh, mkinstalldirs, test-pngtest.sh
+             depcomp, install-sh, mkinstalldirs, test-pngtest.sh, etc.
           contrib
              arm-neon, conftest, examples, gregbook, libtests, pngminim,
              pngminus, pngsuite, tools, visupng
           projects
-             cbuilder5, owatcom, visualc71, vstudio, xcode
+             owatcom, visualc71, vstudio
           scripts
              makefile.*
              *.def (module definition files)
@@ -145,7 +147,7 @@
           pngtest.png
           etc.
       zlib
-          README, *.h, *.c contrib, etc.
+          README, *.h, *.c, contrib, etc.
 
 If the line endings in the files look funny, you may wish to get the other
 distribution of libpng.  It is available in both tar.gz (UNIX style line
@@ -153,28 +155,27 @@
 
 VI. Building with project files
 
-If you are building libpng with MSVC, you can enter the
-libpng projects\visualc71 or vstudio directory and follow the instructions
-in README.txt.
+If you are building libpng with Microsoft Visual Studio, you can enter
+the directory projects\visualc71 or projects\vstudio and follow the
+instructions in README.txt.
 
-Otherwise enter the zlib directory and follow the instructions in zlib/README,
-then come back here and run "configure" or choose the appropriate
-makefile.sys in the scripts directory.
+Otherwise, enter the zlib directory and follow the instructions in
+zlib/README, then come back here and run "configure" or choose the
+appropriate makefile in the scripts directory.
 
 VII. Building with makefiles
 
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example
 
-MSDOS example:
-
-    copy scripts\makefile.msc makefile
-    copy scripts\pnglibconf.h.prebuilt pnglibconf.h
-
 UNIX example:
 
-    cp scripts/makefile.std makefile
-    cp scripts/pnglibconf.h.prebuilt pnglibconf.h
+    cp scripts/makefile.std Makefile
+    make
+
+Windows example:
+
+    nmake -f scripts\makefile.vcwin32
 
 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
@@ -197,30 +198,27 @@
 Some also allow you to run "make test-installed" after you have
 run "make install".
 
-VIII. Configuring libpng for 16-bit platforms
+VIII. Configuring for DOS and other 16-bit platforms
 
-You will want to look into zconf.h to tell zlib (and thus libpng) that
-it cannot allocate more than 64K at a time.  Even if you can, the memory
-won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
-
-IX. Configuring for DOS
+Officially, the support for 16-bit platforms has been removed.
 
 For DOS users who only have access to the lower 640K, you will
 have to limit zlib's memory usage via a png_set_compression_mem_level()
 call.  See zlib.h or zconf.h in the zlib library for more information.
 
-X. Configuring for Medium Model
+You may be or may not be in luck if you target the "large" memory model,
+but all the smaller models ("small", "compact" and "medium") are known
+to be unworkable.  For DOS users who have access beyond the lower 640K,
+a "flat" 32-bit DOS model (such as DJGPP) is strongly recommended.
 
-Libpng's support for medium model has been tested on most of the popular
-compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
-defined, and FAR gets defined to far in pngconf.h, and you should be
-all set.  Everything in the library (except for zlib's structure) is
-expecting far data.  You must use the typedefs with the p or pp on
-the end for pointers (or at least look at them and be careful).  Make
-note that the rows of data are defined as png_bytepp, which is
-an "unsigned char far * far *".
+For DOS users who only have access to the lower 640K, you will have to
+limit zlib's memory usage via a png_set_compression_mem_level() call.
+You will also have to look into zconf.h to tell zlib (and thus libpng)
+that it cannot allocate more than 64K at a time.  Even if you can, the
+memory won't be accessible.  Therefore, you should limit zlib and libpng
+to 64K by defining MAXSEG_64K.
 
-XI. Prepending a prefix to exported symbols
+IX. Prepending a prefix to exported symbols
 
 Starting with libpng-1.6.0, you can configure libpng (when using the
 "configure" script) to prefix all exported symbols by means of the
@@ -231,7 +229,7 @@
 transparent to applications; their function calls get transformed by
 the macros to use the modified names.
 
-XII. Configuring for compiler xxx:
+X. Configuring for compiler xxx:
 
 All includes for libpng are in pngconf.h.  If you need to add, change
 or delete an include, this is the place to do it.
@@ -243,7 +241,7 @@
 files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
 that previously appeared in the public headers.
 
-XIII. Removing unwanted object code
+XI. Removing unwanted object code
 
 There are a bunch of #define's in pngconf.h that control what parts of
 libpng are compiled.  All the defines end in _SUPPORTED.  If you are
@@ -282,7 +280,7 @@
 The size of the library itself should not be an issue, because only
 those sections that are actually used will be loaded into memory.
 
-XIV. Enabling or disabling hardware optimizations
+XII. Enabling or disabling hardware optimizations
 
 Certain hardware capabilities, such as the Intel SSE instructions,
 are normally detected at run time. Enable them with configure options
@@ -332,7 +330,7 @@
 
     cmake . -DPNG_HARDWARE_OPTIMIZATIONS=no
 
-XV. Changes to the build and configuration of libpng in libpng-1.5.x
+XIII. Changes to the build and configuration of libpng in libpng-1.5.x
 
 Details of internal changes to the library code can be found in the CHANGES
 file and in the GIT repository logs.  These will be of no concern to the vast
@@ -423,7 +421,7 @@
 libpng, because than the settings would not accurately reflect the settings
 that were used to build libpng.
 
-XVI. Setjmp/longjmp issues
+XIV. Setjmp/longjmp issues
 
 Libpng uses setjmp()/longjmp() for error handling.  Unfortunately setjmp()
 is known to be not thread-safe on some platforms and we don't know of
@@ -441,7 +439,7 @@
 with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
 and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
 
-XVII. Common linking failures
+XV. Common linking failures
 
 If your application fails to find libpng or zlib entries while linking:
 
@@ -453,12 +451,13 @@
   If you are using the vstudio project, observe the WARNING in
   project/vstudio/README.txt.
 
-XVIII. Other sources of information about libpng:
+XVI. Other sources of information about libpng:
 
 Further information can be found in the README and libpng-manual.txt
 files, in the individual makefiles, in png.h, and the manual pages
 libpng.3 and png.5.
 
+Copyright (c) 2022 Cosmin Truta
 Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
 This document is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
diff --git a/LICENSE b/LICENSE
index e0c5b53..c8ad24e 100644
--- a/LICENSE
+++ b/LICENSE
@@ -4,8 +4,8 @@
 PNG Reference Library License version 2
 ---------------------------------------
 
- * Copyright (c) 1995-2019 The PNG Reference Library Authors.
- * Copyright (c) 2018-2019 Cosmin Truta.
+ * Copyright (c) 1995-2022 The PNG Reference Library Authors.
+ * Copyright (c) 2018-2022 Cosmin Truta.
  * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  * Copyright (c) 1996-1997 Andreas Dilger.
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
diff --git a/METADATA b/METADATA
index 7288841..52e7a95 100644
--- a/METADATA
+++ b/METADATA
@@ -1,3 +1,7 @@
+# This project was upgraded with external_updater.
+# Usage: tools/external_updater/updater.sh update libpng
+# For more info, check https://cs.android.com/android/platform/superproject/+/master:tools/external_updater/README.md
+
 name: "libpng"
 description: "libpng is a PNG image codec."
 third_party {
@@ -5,14 +9,14 @@
     type: GIT
     value: "https://github.com/glennrp/libpng.git"
   }
-  version: "v1.6.37"
+  version: "v1.6.38"
   license_type: NOTICE
-  last_upgrade_date {
-    year: 2019
-    month: 6
-    day: 10
-  }
   security {
-      tag: "NVD-CPE2.3:cpe:/a:libpng:libpng:1.6.37"
+    tag: "NVD-CPE2.3:cpe:/a:libpng:libpng:1.6.37"
+  }
+  last_upgrade_date {
+    year: 2022
+    month: 11
+    day: 16
   }
 }
diff --git a/Makefile.am b/Makefile.am
index 4f621aa..f21107e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -59,8 +59,7 @@
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 TESTS =\
-   tests/pngtest\
-   tests/pngtest-badpngs\
+   tests/pngtest-all\
    tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
    tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
    tests/pngvalid-gamma-expand16-background\
diff --git a/Makefile.in b/Makefile.in
index 81ac1c8..6e7ba28 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.1 from Makefile.am.
+# Makefile.in generated by automake 1.16.5 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2018 Free Software Foundation, Inc.
+# Copyright (C) 1994-2021 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -334,8 +334,8 @@
 MANS = $(dist_man_MANS)
 DATA = $(pkgconfig_DATA)
 HEADERS = $(nodist_pkginclude_HEADERS) $(pkginclude_HEADERS)
-am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) \
-	$(LISP)config.h.in
+am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP) \
+	config.h.in
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
 # *not* preserved.
@@ -352,9 +352,6 @@
   unique=`for i in $$list; do \
     if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
   done | $(am__uniquify_input)`
-ETAGS = etags
-CTAGS = ctags
-CSCOPE = cscope
 AM_RECURSIVE_TARGETS = cscope check recheck
 am__tty_colors_dummy = \
   mgn= red= grn= lgn= blu= brg= std=; \
@@ -511,6 +508,7 @@
   bases='$(TEST_LOGS)'; \
   bases=`for i in $$bases; do echo $$i; done | sed 's/\.log$$//'`; \
   bases=`echo $$bases`
+AM_TESTSUITE_SUMMARY_HEADER = ' for $(PACKAGE_STRING)'
 RECHECK_LOGS = $(TEST_LOGS)
 TEST_SUITE_LOG = test-suite.log
 TEST_EXTENSIONS = @EXEEXT@ .test
@@ -550,6 +548,8 @@
 DIST_ARCHIVES = $(distdir).tar.gz $(distdir).tar.xz
 GZIP_ENV = --best
 DIST_TARGETS = dist-xz dist-gzip
+# Exists only to be overridden by the user if desired.
+AM_DISTCHECK_DVI_TARGET = dvi
 distuninstallcheck_listfiles = find . -type f -print
 am__distuninstallcheck_listfiles = $(distuninstallcheck_listfiles) \
   | sed 's|^\./|$(prefix)/|' | grep -v '$(infodir)/dir$$'
@@ -574,6 +574,8 @@
 CFLAGS = @CFLAGS@
 CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
+CSCOPE = @CSCOPE@
+CTAGS = @CTAGS@
 CYGPATH_W = @CYGPATH_W@
 DEFS = @DEFS@
 DEPDIR = @DEPDIR@
@@ -591,8 +593,10 @@
 ECHO_N = @ECHO_N@
 ECHO_T = @ECHO_T@
 EGREP = @EGREP@
+ETAGS = @ETAGS@
 EXEEXT = @EXEEXT@
 FGREP = @FGREP@
+FILECMD = @FILECMD@
 GREP = @GREP@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
@@ -636,7 +640,6 @@
 # AM_CFLAGS)
 PNG_COPTS = @PNG_COPTS@
 PNG_PREFIX = @PNG_PREFIX@
-POW_LIB = @POW_LIB@
 RANLIB = @RANLIB@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
@@ -695,6 +698,7 @@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
+runstatedir = @runstatedir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 srcdir = @srcdir@
@@ -736,8 +740,7 @@
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 TESTS = \
-   tests/pngtest\
-   tests/pngtest-badpngs\
+   tests/pngtest-all\
    tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
    tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
    tests/pngvalid-gamma-expand16-background\
@@ -1544,7 +1547,7 @@
 	  test x"$$VERBOSE" = x || cat $(TEST_SUITE_LOG);		\
 	fi;								\
 	echo "$${col}$$br$${std}"; 					\
-	echo "$${col}Testsuite summary for $(PACKAGE_STRING)$${std}";	\
+	echo "$${col}Testsuite summary"$(AM_TESTSUITE_SUMMARY_HEADER)"$${std}";	\
 	echo "$${col}$$br$${std}"; 					\
 	create_testsuite_report --maybe-color;				\
 	echo "$$col$$br$$std";						\
@@ -1578,16 +1581,9 @@
 	        am__force_recheck=am--force-recheck \
 	        TEST_LOGS="$$log_list"; \
 	exit $$?
-tests/pngtest.log: tests/pngtest
-	@p='tests/pngtest'; \
-	b='tests/pngtest'; \
-	$(am__check_pre) $(LOG_DRIVER) --test-name "$$f" \
-	--log-file $$b.log --trs-file $$b.trs \
-	$(am__common_driver_flags) $(AM_LOG_DRIVER_FLAGS) $(LOG_DRIVER_FLAGS) -- $(LOG_COMPILE) \
-	"$$tst" $(AM_TESTS_FD_REDIRECT)
-tests/pngtest-badpngs.log: tests/pngtest-badpngs
-	@p='tests/pngtest-badpngs'; \
-	b='tests/pngtest-badpngs'; \
+tests/pngtest-all.log: tests/pngtest-all
+	@p='tests/pngtest-all'; \
+	b='tests/pngtest-all'; \
 	$(am__check_pre) $(LOG_DRIVER) --test-name "$$f" \
 	--log-file $$b.log --trs-file $$b.trs \
 	$(am__common_driver_flags) $(AM_LOG_DRIVER_FLAGS) $(LOG_DRIVER_FLAGS) -- $(LOG_COMPILE) \
@@ -1823,7 +1819,6 @@
 @am__EXEEXT_TRUE@	--log-file $$b.log --trs-file $$b.trs \
 @am__EXEEXT_TRUE@	$(am__common_driver_flags) $(AM_TEST_LOG_DRIVER_FLAGS) $(TEST_LOG_DRIVER_FLAGS) -- $(TEST_LOG_COMPILE) \
 @am__EXEEXT_TRUE@	"$$tst" $(AM_TESTS_FD_REDIRECT)
-
 distdir: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) distdir-am
 
@@ -1884,6 +1879,10 @@
 	tardir=$(distdir) && $(am__tar) | XZ_OPT=$${XZ_OPT--e} xz -c >$(distdir).tar.xz
 	$(am__post_remove_distdir)
 
+dist-zstd: distdir
+	tardir=$(distdir) && $(am__tar) | zstd -c $${ZSTD_CLEVEL-$${ZSTD_OPT--19}} >$(distdir).tar.zst
+	$(am__post_remove_distdir)
+
 dist-tarZ: distdir
 	@echo WARNING: "Support for distribution archives compressed with" \
 		       "legacy program 'compress' is deprecated." >&2
@@ -1926,6 +1925,8 @@
 	  eval GZIP= gzip $(GZIP_ENV) -dc $(distdir).shar.gz | unshar ;;\
 	*.zip*) \
 	  unzip $(distdir).zip ;;\
+	*.tar.zst*) \
+	  zstd -dc $(distdir).tar.zst | $(am__untar) ;;\
 	esac
 	chmod -R a-w $(distdir)
 	chmod u+w $(distdir)
@@ -1941,7 +1942,7 @@
 	    $(DISTCHECK_CONFIGURE_FLAGS) \
 	    --srcdir=../.. --prefix="$$dc_install_base" \
 	  && $(MAKE) $(AM_MAKEFLAGS) \
-	  && $(MAKE) $(AM_MAKEFLAGS) dvi \
+	  && $(MAKE) $(AM_MAKEFLAGS) $(AM_DISTCHECK_DVI_TARGET) \
 	  && $(MAKE) $(AM_MAKEFLAGS) check \
 	  && $(MAKE) $(AM_MAKEFLAGS) install \
 	  && $(MAKE) $(AM_MAKEFLAGS) installcheck \
@@ -2001,13 +2002,16 @@
 		$(HEADERS) config.h
 install-binPROGRAMS: install-libLTLIBRARIES
 
+install-checkPROGRAMS: install-libLTLIBRARIES
+
 installdirs:
 	for dir in "$(DESTDIR)$(bindir)" "$(DESTDIR)$(libdir)" "$(DESTDIR)$(bindir)" "$(DESTDIR)$(man3dir)" "$(DESTDIR)$(man5dir)" "$(DESTDIR)$(pkgconfigdir)" "$(DESTDIR)$(pkgincludedir)" "$(DESTDIR)$(pkgincludedir)"; do \
 	  test -z "$$dir" || $(MKDIR_P) "$$dir"; \
 	done
 install: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) install-am
-install-exec: install-exec-am
+install-exec: $(BUILT_SOURCES)
+	$(MAKE) $(AM_MAKEFLAGS) install-exec-am
 install-data: install-data-am
 uninstall: uninstall-am
 
@@ -2208,22 +2212,23 @@
 uninstall-man: uninstall-man3 uninstall-man5
 
 .MAKE: all check check-am install install-am install-data-am \
-	install-exec-am install-strip uninstall-am
+	install-exec install-exec-am install-strip uninstall-am
 
 .PHONY: CTAGS GTAGS TAGS all all-am am--depfiles am--refresh check \
 	check-TESTS check-am clean clean-binPROGRAMS \
 	clean-checkPROGRAMS clean-cscope clean-generic \
 	clean-libLTLIBRARIES clean-libtool cscope cscopelist-am ctags \
 	ctags-am dist dist-all dist-bzip2 dist-gzip dist-hook \
-	dist-lzip dist-shar dist-tarZ dist-xz dist-zip distcheck \
-	distclean distclean-compile distclean-generic distclean-hdr \
-	distclean-libtool distclean-tags distcleancheck distdir \
-	distuninstallcheck dvi dvi-am html html-am info info-am \
-	install install-am install-binPROGRAMS install-binSCRIPTS \
-	install-data install-data-am install-data-hook install-dvi \
-	install-dvi-am install-exec install-exec-am install-exec-hook \
-	install-html install-html-am install-info install-info-am \
-	install-libLTLIBRARIES install-man install-man3 install-man5 \
+	dist-lzip dist-shar dist-tarZ dist-xz dist-zip dist-zstd \
+	distcheck distclean distclean-compile distclean-generic \
+	distclean-hdr distclean-libtool distclean-tags distcleancheck \
+	distdir distuninstallcheck dvi dvi-am html html-am info \
+	info-am install install-am install-binPROGRAMS \
+	install-binSCRIPTS install-data install-data-am \
+	install-data-hook install-dvi install-dvi-am install-exec \
+	install-exec-am install-exec-hook install-html install-html-am \
+	install-info install-info-am install-libLTLIBRARIES \
+	install-man install-man3 install-man5 \
 	install-nodist_pkgincludeHEADERS install-pdf install-pdf-am \
 	install-pkgconfigDATA install-pkgincludeHEADERS install-ps \
 	install-ps-am install-strip installcheck installcheck-am \
diff --git a/README b/README
index cfc1f0e..e6e72aa 100644
--- a/README
+++ b/README
@@ -1,12 +1,12 @@
-README for libpng version 1.6.37 - April 14, 2019
-=================================================
+README for libpng version 1.6.38
+================================
 
 See the note about version numbers near the top of png.h.
 See INSTALL for instructions on how to install libpng.
 
 Libpng comes in several distribution formats.  Get libpng-*.tar.gz or
-libpng-*.tar.xz or if you want UNIX-style line endings in the text
-files, or lpng*.7z or lpng*.zip if you want DOS-style line endings.
+libpng-*.tar.xz if you want UNIX-style line endings in the text files,
+or lpng*.7z or lpng*.zip if you want DOS-style line endings.
 
 Version 0.89 was the first official release of libpng.  Don't let the
 fact that it's the first release fool you.  The libpng library has been
diff --git a/aclocal.m4 b/aclocal.m4
index bc18c34..89201a2 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.16.1 -*- Autoconf -*-
+# generated automatically by aclocal 1.16.5 -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -14,13 +14,13 @@
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
-m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.69],,
-[m4_warning([this file was generated for autoconf 2.69.
+m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.71],,
+[m4_warning([this file was generated for autoconf 2.71.
 You have another version of autoconf.  It may work, but is not guaranteed to.
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
 
-# Copyright (C) 2002-2018 Free Software Foundation, Inc.
+# Copyright (C) 2002-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -35,7 +35,7 @@
 [am__api_version='1.16'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.16.1], [],
+m4_if([$1], [1.16.5], [],
       [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
 
@@ -51,14 +51,14 @@
 # Call AM_AUTOMAKE_VERSION and AM_AUTOMAKE_VERSION so they can be traced.
 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.16.1])dnl
+[AM_AUTOMAKE_VERSION([1.16.5])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 
 # Figure out how to run the assembler.                      -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -78,7 +78,7 @@
 
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -130,7 +130,7 @@
 
 # AM_CONDITIONAL                                            -*- Autoconf -*-
 
-# Copyright (C) 1997-2018 Free Software Foundation, Inc.
+# Copyright (C) 1997-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -161,7 +161,7 @@
 Usually this means the macro was only invoked conditionally.]])
 fi])])
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -352,7 +352,7 @@
 
 # Generate code to set up dependency tracking.              -*- Autoconf -*-
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -391,7 +391,9 @@
   done
   if test $am_rc -ne 0; then
     AC_MSG_FAILURE([Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  Try re-running configure with the
+    for automatic dependency tracking.  If GNU make was not used, consider
+    re-running the configure script with MAKE="gmake" (or whatever is
+    necessary).  You can also try re-running configure with the
     '--disable-dependency-tracking' option to at least be able to build
     the package (albeit without support for automatic dependency tracking).])
   fi
@@ -418,7 +420,7 @@
 
 # Do all the work for Automake.                             -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -446,6 +448,10 @@
 # release and drop the old call support.
 AC_DEFUN([AM_INIT_AUTOMAKE],
 [AC_PREREQ([2.65])dnl
+m4_ifdef([_$0_ALREADY_INIT],
+  [m4_fatal([$0 expanded multiple times
+]m4_defn([_$0_ALREADY_INIT]))],
+  [m4_define([_$0_ALREADY_INIT], m4_expansion_stack)])dnl
 dnl Autoconf wants to disallow AM_ names.  We explicitly allow
 dnl the ones we care about.
 m4_pattern_allow([^AM_[A-Z]+FLAGS$])dnl
@@ -482,7 +488,7 @@
 [_AM_SET_OPTIONS([$1])dnl
 dnl Diagnose old-style AC_INIT with new-style AM_AUTOMAKE_INIT.
 m4_if(
-  m4_ifdef([AC_PACKAGE_NAME], [ok]):m4_ifdef([AC_PACKAGE_VERSION], [ok]),
+  m4_ifset([AC_PACKAGE_NAME], [ok]):m4_ifset([AC_PACKAGE_VERSION], [ok]),
   [ok:ok],,
   [m4_fatal([AC_INIT should be called with package and version arguments])])dnl
  AC_SUBST([PACKAGE], ['AC_PACKAGE_TARNAME'])dnl
@@ -534,6 +540,20 @@
 		  [m4_define([AC_PROG_OBJCXX],
 			     m4_defn([AC_PROG_OBJCXX])[_AM_DEPENDENCIES([OBJCXX])])])dnl
 ])
+# Variables for tags utilities; see am/tags.am
+if test -z "$CTAGS"; then
+  CTAGS=ctags
+fi
+AC_SUBST([CTAGS])
+if test -z "$ETAGS"; then
+  ETAGS=etags
+fi
+AC_SUBST([ETAGS])
+if test -z "$CSCOPE"; then
+  CSCOPE=cscope
+fi
+AC_SUBST([CSCOPE])
+
 AC_REQUIRE([AM_SILENT_RULES])dnl
 dnl The testsuite driver may need to know about EXEEXT, so add the
 dnl 'am__EXEEXT' conditional if _AM_COMPILER_EXEEXT was seen.  This
@@ -615,7 +635,7 @@
 done
 echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_count])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -636,7 +656,7 @@
 fi
 AC_SUBST([install_sh])])
 
-# Copyright (C) 2003-2018 Free Software Foundation, Inc.
+# Copyright (C) 2003-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -658,7 +678,7 @@
 # Add --enable-maintainer-mode option to configure.         -*- Autoconf -*-
 # From Jim Meyering
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -693,7 +713,7 @@
 
 # Check to see how 'make' treats includes.	            -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -736,7 +756,7 @@
 
 # Fake the existence of programs that GNU maintainers use.  -*- Autoconf -*-
 
-# Copyright (C) 1997-2018 Free Software Foundation, Inc.
+# Copyright (C) 1997-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -757,12 +777,7 @@
 [AC_REQUIRE([AM_AUX_DIR_EXPAND])dnl
 AC_REQUIRE_AUX_FILE([missing])dnl
 if test x"${MISSING+set}" != xset; then
-  case $am_aux_dir in
-  *\ * | *\	*)
-    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
-  *)
-    MISSING="\${SHELL} $am_aux_dir/missing" ;;
-  esac
+  MISSING="\${SHELL} '$am_aux_dir/missing'"
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
@@ -775,7 +790,7 @@
 
 # Helper functions for option handling.                     -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -804,7 +819,7 @@
 AC_DEFUN([_AM_IF_OPTION],
 [m4_ifset(_AM_MANGLE_OPTION([$1]), [$2], [$3])])
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -851,7 +866,7 @@
 # For backward compatibility.
 AC_DEFUN_ONCE([AM_PROG_CC_C_O], [AC_REQUIRE([AC_PROG_CC])])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -870,7 +885,7 @@
 
 # Check to make sure that the build environment is sane.    -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -951,7 +966,7 @@
 rm -f conftest.file
 ])
 
-# Copyright (C) 2009-2018 Free Software Foundation, Inc.
+# Copyright (C) 2009-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1011,7 +1026,7 @@
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 ])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1039,7 +1054,7 @@
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 AC_SUBST([INSTALL_STRIP_PROGRAM])])
 
-# Copyright (C) 2006-2018 Free Software Foundation, Inc.
+# Copyright (C) 2006-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1058,7 +1073,7 @@
 
 # Check how to create a tarball.                            -*- Autoconf -*-
 
-# Copyright (C) 2004-2018 Free Software Foundation, Inc.
+# Copyright (C) 2004-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
diff --git a/arm/arm_init.c b/arm/arm_init.c
index a34ecdb..ab22525 100644
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@@ -1,7 +1,7 @@
 
 /* arm_init.c - NEON optimised filter functions
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 2014,2016 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
  *
@@ -10,9 +10,7 @@
  * and license in png.h
  */
 
-/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
- * called.
- */
+/* This module requires POSIX 1003.1 functions. */
 #define _POSIX_SOURCE 1
 
 #include "../pngpriv.h"
@@ -33,21 +31,23 @@
  * has partial support is contrib/arm-neon/linux.c - a generic Linux
  * implementation which reads /proc/cpufino.
  */
+#include <signal.h> /* for sig_atomic_t */
+
 #ifndef PNG_ARM_NEON_FILE
-#  ifdef __linux__
-#     define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+#  if defined(__aarch64__) || defined(_M_ARM64)
+     /* ARM Neon is expected to be unconditionally available on ARM64. */
+#    error "PNG_ARM_NEON_CHECK_SUPPORTED must not be defined on this platform"
+#  elif defined(__linux__)
+#    define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+#  else
+#    error "No support for run-time ARM Neon checking; use compile-time options"
 #  endif
 #endif
 
-#ifdef PNG_ARM_NEON_FILE
-
-#include <signal.h> /* for sig_atomic_t */
 static int png_have_neon(png_structp png_ptr);
-#include PNG_ARM_NEON_FILE
-
-#else  /* PNG_ARM_NEON_FILE */
-#  error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
-#endif /* PNG_ARM_NEON_FILE */
+#ifdef PNG_ARM_NEON_FILE
+#  include PNG_ARM_NEON_FILE
+#endif
 #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
 
 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
diff --git a/arm/filter_neon_intrinsics.c b/arm/filter_neon_intrinsics.c
index 553c0be..4466d48 100644
--- a/arm/filter_neon_intrinsics.c
+++ b/arm/filter_neon_intrinsics.c
@@ -18,7 +18,7 @@
 /* This code requires -mfpu=neon on the command line: */
 #if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
 
-#if defined(_MSC_VER) && defined(_M_ARM64)
+#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_ARM64)
 #  include <arm64_neon.h>
 #else
 #  include <arm_neon.h>
diff --git a/arm/palette_neon_intrinsics.c b/arm/palette_neon_intrinsics.c
index b4d1fd2..92c7d6f 100644
--- a/arm/palette_neon_intrinsics.c
+++ b/arm/palette_neon_intrinsics.c
@@ -14,7 +14,7 @@
 
 #if PNG_ARM_NEON_IMPLEMENTATION == 1
 
-#if defined(_MSC_VER) && defined(_M_ARM64)
+#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_ARM64)
 #  include <arm64_neon.h>
 #else
 #  include <arm_neon.h>
@@ -30,8 +30,6 @@
    int num_trans = png_ptr->num_trans;
    int i;
 
-   png_debug(1, "in png_riffle_palette_neon");
-
    /* Initially black, opaque. */
    uint8x16x4_t w = {{
       vdupq_n_u8(0x00),
@@ -40,6 +38,8 @@
       vdupq_n_u8(0xff),
    }};
 
+   png_debug(1, "in png_riffle_palette_neon");
+
    /* First, riffle the RGB colours into an RGBA8 palette.
     * The alpha component is set to opaque for now.
     */
@@ -65,11 +65,12 @@
    png_uint_32 row_width = row_info->width;
    const png_uint_32 *riffled_palette =
       (const png_uint_32 *)png_ptr->riffled_palette;
-   const png_int_32 pixels_per_chunk = 4;
-   int i;
+   const png_uint_32 pixels_per_chunk = 4;
+   png_uint_32 i;
 
    png_debug(1, "in png_do_expand_palette_rgba8_neon");
 
+   PNG_UNUSED(row)
    if (row_width < pixels_per_chunk)
       return 0;
 
@@ -109,10 +110,11 @@
    png_uint_32 row_width = row_info->width;
    png_const_bytep palette = (png_const_bytep)png_ptr->palette;
    const png_uint_32 pixels_per_chunk = 8;
-   int i;
+   png_uint_32 i;
 
    png_debug(1, "in png_do_expand_palette_rgb8_neon");
 
+   PNG_UNUSED(row)
    if (row_width <= pixels_per_chunk)
       return 0;
 
diff --git a/ci/ci_autotools.sh b/ci/ci_autotools.sh
new file mode 100755
index 0000000..0728540
--- /dev/null
+++ b/ci/ci_autotools.sh
@@ -0,0 +1,117 @@
+#!/usr/bin/env bash
+set -e
+
+# ci_autotools.sh
+# Continuously integrate libpng using the GNU Autotools.
+#
+# Copyright (c) 2019-2022 Cosmin Truta.
+#
+# This software is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h.
+
+CI_SCRIPTNAME="$(basename "$0")"
+CI_SCRIPTDIR="$(cd "$(dirname "$0")" && pwd)"
+CI_SRCDIR="$(dirname "$CI_SCRIPTDIR")"
+CI_BUILDDIR="$CI_SRCDIR/out/autotools.build"
+CI_INSTALLDIR="$CI_SRCDIR/out/autotools.install"
+
+function ci_info {
+    printf >&2 "%s: %s\\n" "$CI_SCRIPTNAME" "$*"
+}
+
+function ci_err {
+    printf >&2 "%s: error: %s\\n" "$CI_SCRIPTNAME" "$*"
+    exit 2
+}
+
+function ci_spawn {
+    printf >&2 "%s: executing:" "$CI_SCRIPTNAME"
+    printf >&2 " %q" "$@"
+    printf >&2 "\\n"
+    "$@"
+}
+
+function ci_init_autotools {
+    CI_SYSTEM_NAME="$(uname -s)"
+    CI_MACHINE_NAME="$(uname -m)"
+    CI_MAKE="${CI_MAKE:-make}"
+    # Set CI_CC to cc by default, if the cc command is available.
+    # The configure script defaults CC to gcc, which is not always a good idea.
+    [[ -x $(command -v cc) ]] && CI_CC="${CI_CC:-cc}"
+    # Ensure that the CI_ variables that cannot be customized reliably are not initialized.
+    [[ ! $CI_CONFIGURE_VARS ]] || ci_err "unexpected: \$CI_CONFIGURE_VARS='$CI_CONFIGURE_VARS'"
+    [[ ! $CI_MAKE_VARS ]] || ci_err "unexpected: \$CI_MAKE_VARS='$CI_MAKE_VARS'"
+}
+
+function ci_trace_autotools {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "system name: $CI_SYSTEM_NAME"
+    ci_info "machine hardware name: $CI_MACHINE_NAME"
+    ci_info "source directory: $CI_SRCDIR"
+    ci_info "build directory: $CI_BUILDDIR"
+    ci_info "install directory: $CI_INSTALLDIR"
+    ci_info "environment option: \$CI_CONFIGURE_FLAGS: '$CI_CONFIGURE_FLAGS'"
+    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
+    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
+    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_LD: '$CI_LD'"
+    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
+    [[ $CI_CC ]] &&
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    [[ $CI_CPP ]] &&
+        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
+    [[ $CI_AR ]] &&
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    [[ $CI_RANLIB ]] &&
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    [[ $CI_LD ]] &&
+        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_build_autotools {
+    ci_info "## START OF BUILD ##"
+    # Export the configure build environment.
+    [[ $CI_CC ]] && ci_spawn export CC="$CI_CC"
+    [[ $CI_CC_FLAGS ]] && ci_spawn export CFLAGS="$CI_CC_FLAGS"
+    [[ $CI_CPP ]] && ci_spawn export CPP="$CI_CPP"
+    [[ $CI_CPP_FLAGS ]] && ci_spawn export CPPFLAGS="$CI_CPP_FLAGS"
+    [[ $CI_AR ]] && ci_spawn export AR="$CI_AR"
+    [[ $CI_RANLIB ]] && ci_spawn export RANLIB="$CI_RANLIB"
+    [[ $CI_LD ]] && ci_spawn export CPP="$CI_LD"
+    [[ $CI_LD_FLAGS ]] && ci_spawn export LDFLAGS="$CI_LD_FLAGS"
+    [[ $CI_SANITIZERS ]] && {
+        ci_spawn export CFLAGS="-fsanitize=$CI_SANITIZERS ${CFLAGS:-"-O2"}"
+        ci_spawn export LDFLAGS="-fsanitize=$CI_SANITIZERS $LDFLAGS"
+    }
+    # Build and install.
+    ci_spawn rm -fr "$CI_BUILDDIR" "$CI_INSTALLDIR"
+    ci_spawn mkdir -p "$CI_BUILDDIR"
+    ci_spawn cd "$CI_BUILDDIR"
+    ci_spawn "$CI_SRCDIR/configure" --prefix="$CI_INSTALLDIR" $CI_CONFIGURE_FLAGS
+    ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS
+    [[ $CI_NO_TEST ]] || ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS test
+    [[ $CI_NO_INSTALL ]] || ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS install
+    [[ $CI_NO_CLEAN ]] || ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS clean
+    [[ $CI_NO_CLEAN ]] || ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS distclean
+    ci_info "## END OF BUILD ##"
+}
+
+ci_init_autotools
+ci_trace_autotools
+[[ $# -eq 0 ]] || {
+    ci_info "note: this program accepts environment options only"
+    ci_err "unexpected command arguments: '$*'"
+}
+ci_build_autotools
diff --git a/ci/ci_cmake.sh b/ci/ci_cmake.sh
new file mode 100755
index 0000000..71af270
--- /dev/null
+++ b/ci/ci_cmake.sh
@@ -0,0 +1,169 @@
+#!/usr/bin/env bash
+set -e
+
+# ci_cmake.sh
+# Continuously integrate libpng using CMake.
+#
+# Copyright (c) 2019-2022 Cosmin Truta.
+#
+# This software is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h.
+
+CI_SCRIPTNAME="$(basename "$0")"
+CI_SCRIPTDIR="$(cd "$(dirname "$0")" && pwd)"
+CI_SRCDIR="$(dirname "$CI_SCRIPTDIR")"
+CI_BUILDDIR="$CI_SRCDIR/out/cmake.build"
+CI_INSTALLDIR="$CI_SRCDIR/out/cmake.install"
+
+function ci_info {
+    printf >&2 "%s: %s\\n" "$CI_SCRIPTNAME" "$*"
+}
+
+function ci_err {
+    printf >&2 "%s: error: %s\\n" "$CI_SCRIPTNAME" "$*"
+    exit 2
+}
+
+function ci_spawn {
+    printf >&2 "%s: executing:" "$CI_SCRIPTNAME"
+    printf >&2 " %q" "$@"
+    printf >&2 "\\n"
+    "$@"
+}
+
+function ci_init_cmake {
+    CI_SYSTEM_NAME="$(uname -s)"
+    CI_MACHINE_NAME="$(uname -m)"
+    CI_CMAKE="${CI_CMAKE:-cmake}"
+    CI_CTEST="${CI_CTEST:-ctest}"
+    CI_CMAKE_BUILD_TYPE="${CI_CMAKE_BUILD_TYPE:-Release}"
+    [[ -x $(command -v ninja) ]] && CI_CMAKE_GENERATOR="${CI_CMAKE_GENERATOR:-Ninja}"
+    if [[ $CI_CMAKE_GENERATOR == "Visual Studio"* ]]
+    then
+        # Initialize the CI_...DIR_NATIVE variables, for the benefit of
+        # the native Windows build tools. The regular CI_...DIR variables
+        # can only be used inside Bash-on-Windows.
+        mkdir -p "$CI_BUILDDIR"
+        mkdir -p "$CI_INSTALLDIR"
+        if [[ -x $CYGPATH ]]
+        then
+            CI_SRCDIR_NATIVE="$("$CYGPATH" -w "$CI_SRCDIR")"
+            CI_BUILDDIR_NATIVE="$("$CYGPATH" -w "$CI_BUILDDIR")"
+            CI_INSTALLDIR_NATIVE="$("$CYGPATH" -w "$CI_INSTALLDIR")"
+        else
+            CI_SRCDIR_NATIVE="$(cd "$CI_SRCDIR" ; pwd -W || pwd -P)"
+            CI_BUILDDIR_NATIVE="$(cd "$CI_BUILDDIR" ; pwd -W || pwd -P)"
+            CI_INSTALLDIR_NATIVE="$(cd "$CI_INSTALLDIR" ; pwd -W || pwd -P)"
+        fi
+        # Clean up incidental mixtures of Windows and Bash-on-Windows
+        # environment variables, to avoid confusing MSBuild.
+        [[ $TEMP && ( $Temp || $temp ) ]] && unset TEMP
+        [[ $TMP && ( $Tmp || $tmp ) ]] && unset TMP
+        # Ensure that CI_CMAKE_GENERATOR_PLATFORM is initialized for this generator.
+        [[ $CI_CMAKE_GENERATOR_PLATFORM ]] || ci_err "missing: \$CI_CMAKE_GENERATOR_PLATFORM"
+    fi
+}
+
+function ci_trace_cmake {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "system name: $CI_SYSTEM_NAME"
+    ci_info "machine hardware name: $CI_MACHINE_NAME"
+    ci_info "source directory: $CI_SRCDIR"
+    [[ $CI_SRCDIR_NATIVE ]] &&
+        ci_info "source directory (native): $CI_SRCDIR_NATIVE"
+    ci_info "build directory: $CI_BUILDDIR"
+    [[ $CI_BUILDDIR_NATIVE ]] &&
+        ci_info "build directory (native): $CI_BUILDDIR_NATIVE"
+    ci_info "install directory: $CI_INSTALLDIR"
+    [[ $CI_INSTALLDIR_NATIVE ]] &&
+        ci_info "install directory (native): $CI_INSTALLDIR_NATIVE"
+    ci_info "environment option: \$CI_CMAKE: '$CI_CMAKE'"
+    ci_info "environment option: \$CI_CMAKE_GENERATOR: '$CI_CMAKE_GENERATOR'"
+    ci_info "environment option: \$CI_CMAKE_GENERATOR_PLATFORM: '$CI_CMAKE_GENERATOR_PLATFORM'"
+    ci_info "environment option: \$CI_CMAKE_BUILD_TYPE: '$CI_CMAKE_BUILD_TYPE'"
+    ci_info "environment option: \$CI_CMAKE_BUILD_FLAGS: '$CI_CMAKE_BUILD_FLAGS'"
+    ci_info "environment option: \$CI_CMAKE_VARS: '$CI_CMAKE_VARS'"
+    ci_info "environment option: \$CI_CTEST: '$CI_CTEST'"
+    ci_info "environment option: \$CI_CTEST_FLAGS: '$CI_CTEST_FLAGS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_CMAKE: $(command -V "$CI_CMAKE")"
+    ci_info "executable: \$CI_CTEST: $(command -V "$CI_CTEST")"
+    [[ $CI_CMAKE_GENERATOR == *"Ninja"* ]] &&
+        ci_info "executable: $(command -V ninja)"
+    [[ $CI_CC ]] &&
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    [[ $CI_AR ]] &&
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    [[ $CI_RANLIB ]] &&
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_build_cmake {
+    ci_info "## START OF BUILD ##"
+    ci_spawn "$(command -v "$CI_CMAKE")" --version
+    ci_spawn "$(command -v "$CI_CTEST")" --version
+    # Initialize ALL_CC_FLAGS as a string.
+    local ALL_CC_FLAGS="$CI_CC_FLAGS"
+    [[ $CI_SANITIZERS ]] && ALL_CC_FLAGS="-fsanitize=$CI_SANITIZERS $ALL_CC_FLAGS"
+    # Initialize ALL_CMAKE_VARS, ALL_CMAKE_BUILD_FLAGS and ALL_CTEST_FLAGS as arrays.
+    local -a ALL_CMAKE_VARS=()
+    [[ $CI_CC ]] && ALL_CMAKE_VARS+=(-DCMAKE_C_COMPILER="$CI_CC")
+    [[ $ALL_CC_FLAGS ]] && ALL_CMAKE_VARS+=(-DCMAKE_C_FLAGS="$ALL_CC_FLAGS")
+    [[ $CI_AR ]] && ALL_CMAKE_VARS+=(-DCMAKE_AR="$CI_AR")
+    [[ $CI_RANLIB ]] && ALL_CMAKE_VARS+=(-DCMAKE_RANLIB="$CI_RANLIB")
+    ALL_CMAKE_VARS+=(-DCMAKE_BUILD_TYPE="$CI_CMAKE_BUILD_TYPE")
+    ALL_CMAKE_VARS+=(-DCMAKE_VERBOSE_MAKEFILE=ON)
+    [[ $CI_NO_TEST ]] && ALL_CMAKE_VARS+=(-DPNG_TESTS=OFF)
+    ALL_CMAKE_VARS+=($CI_CMAKE_VARS)
+    local -a ALL_CMAKE_BUILD_FLAGS=($CI_CMAKE_BUILD_FLAGS)
+    local -a ALL_CTEST_FLAGS=($CI_CTEST_FLAGS)
+    # Initialize SRCDIR_NATIVE and INSTALLDIR_NATIVE.
+    local SRCDIR_NATIVE="${CI_SRCDIR_NATIVE:-"$CI_SRCDIR"}"
+    local INSTALLDIR_NATIVE="${CI_INSTALLDIR_NATIVE:-"$CI_INSTALLDIR"}"
+    # Export the CMake environment variables.
+    [[ $CI_CMAKE_GENERATOR ]] &&
+        ci_spawn export CMAKE_GENERATOR="$CI_CMAKE_GENERATOR"
+    [[ $CI_CMAKE_GENERATOR_PLATFORM ]] &&
+        ci_spawn export CMAKE_GENERATOR_PLATFORM="$CI_CMAKE_GENERATOR_PLATFORM"
+    # Build and install.
+    ci_spawn rm -fr "$CI_BUILDDIR" "$CI_INSTALLDIR"
+    ci_spawn mkdir -p "$CI_BUILDDIR"
+    ci_spawn cd "$CI_BUILDDIR"
+    ci_spawn "$CI_CMAKE" "${ALL_CMAKE_VARS[@]}" \
+                         -DCMAKE_INSTALL_PREFIX="$INSTALLDIR_NATIVE" \
+                         "$SRCDIR_NATIVE"
+    ci_spawn "$CI_CMAKE" --build . \
+                         --config "$CI_CMAKE_BUILD_TYPE" \
+                         "${ALL_CMAKE_BUILD_FLAGS[@]}"
+    [[ $CI_NO_TEST ]] ||
+        ci_spawn "$CI_CTEST" --build-config "$CI_CMAKE_BUILD_TYPE" \
+                             "${ALL_CTEST_FLAGS[@]}"
+    [[ $CI_NO_INSTALL ]] ||
+        ci_spawn "$CI_CMAKE" --build . \
+                             --config "$CI_CMAKE_BUILD_TYPE" \
+                             --target install \
+                             "${ALL_CMAKE_BUILD_FLAGS[@]}"
+    [[ $CI_NO_CLEAN ]] ||
+        ci_spawn "$CI_CMAKE" --build . \
+                             --config "$CI_CMAKE_BUILD_TYPE" \
+                             --target clean \
+                             "${ALL_CMAKE_BUILD_FLAGS[@]}"
+    ci_info "## END OF BUILD ##"
+}
+
+ci_init_cmake
+ci_trace_cmake
+[[ $# -eq 0 ]] || {
+    ci_info "note: this program accepts environment options only"
+    ci_err "unexpected command arguments: '$*'"
+}
+ci_build_cmake
diff --git a/ci/ci_legacy.sh b/ci/ci_legacy.sh
new file mode 100755
index 0000000..cfe1f53
--- /dev/null
+++ b/ci/ci_legacy.sh
@@ -0,0 +1,147 @@
+#!/usr/bin/env bash
+set -e
+
+# ci_legacy.sh
+# Continuously integrate libpng using the legacy makefiles.
+#
+# Copyright (c) 2019-2022 Cosmin Truta.
+#
+# This software is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h.
+
+CI_SCRIPTNAME="$(basename "$0")"
+CI_SCRIPTDIR="$(cd "$(dirname "$0")" && pwd)"
+CI_SRCDIR="$(dirname "$CI_SCRIPTDIR")"
+CI_BUILDDIR="$CI_SRCDIR"
+
+function ci_info {
+    printf >&2 "%s: %s\\n" "$CI_SCRIPTNAME" "$*"
+}
+
+function ci_err {
+    printf >&2 "%s: error: %s\\n" "$CI_SCRIPTNAME" "$*"
+    exit 2
+}
+
+function ci_spawn {
+    printf >&2 "%s: executing:" "$CI_SCRIPTNAME"
+    printf >&2 " %q" "$@"
+    printf >&2 "\\n"
+    "$@"
+}
+
+function ci_init_legacy {
+    CI_SYSTEM_NAME="$(uname -s)"
+    CI_MACHINE_NAME="$(uname -m)"
+    CI_MAKE="${CI_MAKE:-make}"
+    case "$CI_SYSTEM_NAME" in
+    ( Darwin | *BSD | DragonFly )
+        [[ -x $(command -v clang) ]] && CI_CC="${CI_CC:-clang}" ;;
+    ( * )
+        [[ -x $(command -v gcc) ]] && CI_CC="${CI_CC:-gcc}" ;;
+    esac
+    CI_CC="${CI_CC:-cc}"
+    case "$CI_CC" in
+    ( *clang* )
+        CI_LEGACY_MAKEFILES="${CI_LEGACY_MAKEFILES:-"scripts/makefile.clang"}" ;;
+    ( *gcc* )
+        CI_LEGACY_MAKEFILES="${CI_LEGACY_MAKEFILES:-"scripts/makefile.gcc"}" ;;
+    ( cc | c89 | c99 )
+        CI_LEGACY_MAKEFILES="${CI_LEGACY_MAKEFILES:-"scripts/makefile.std"}" ;;
+    esac
+    CI_LD="${CI_LD:-"$CI_CC"}"
+    CI_LIBS="${CI_LIBS:-"-lz -lm"}"
+}
+
+function ci_trace_legacy {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "system name: $CI_SYSTEM_NAME"
+    ci_info "machine hardware name: $CI_MACHINE_NAME"
+    ci_info "source directory: $CI_SRCDIR"
+    ci_info "build directory: $CI_BUILDDIR"
+    ci_info "environment option: \$CI_LEGACY_MAKEFILES: '$CI_LEGACY_MAKEFILES'"
+    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
+    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
+    ci_info "environment option: \$CI_MAKE_VARS: '$CI_MAKE_VARS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
+    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_LD: '$CI_LD'"
+    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
+    ci_info "environment option: \$CI_LIBS: '$CI_LIBS'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
+    [[ $CI_CC ]] &&
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    [[ $CI_CPP ]] &&
+        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
+    [[ $CI_AR ]] &&
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    [[ $CI_RANLIB ]] &&
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    [[ $CI_LD ]] &&
+        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_build_legacy {
+    ci_info "## START OF BUILD ##"
+    # Initialize ALL_CC_FLAGS and ALL_LD_FLAGS as strings.
+    local ALL_CC_FLAGS="$CI_CC_FLAGS"
+    local ALL_LD_FLAGS="$CI_LD_FLAGS"
+    [[ $CI_SANITIZERS ]] && {
+        ALL_CC_FLAGS="-fsanitize=$CI_SANITIZERS ${ALL_CC_FLAGS:-"-O2"}"
+        ALL_LD_FLAGS="-fsanitize=$CI_SANITIZERS $ALL_LD_FLAGS"
+    }
+    # Initialize ALL_MAKE_FLAGS and ALL_MAKE_VARS as arrays.
+    local -a ALL_MAKE_FLAGS=($CI_MAKE_FLAGS)
+    local -a ALL_MAKE_VARS=()
+    [[ $CI_CC ]] && ALL_MAKE_VARS+=(CC="$CI_CC")
+    [[ $ALL_CC_FLAGS ]] && ALL_MAKE_VARS+=(CFLAGS="$ALL_CC_FLAGS")
+    [[ $CI_CPP ]] && ALL_MAKE_VARS+=(CPP="$CI_CPP")
+    [[ $CI_CPP_FLAGS ]] && ALL_MAKE_VARS+=(CPPFLAGS="$CI_CPP_FLAGS")
+    [[ $CI_AR ]] && ALL_MAKE_VARS+=(
+        AR="${CI_AR:-ar}"
+        AR_RC="${CI_AR:-ar} rc"
+    )
+    [[ $CI_RANLIB ]] && ALL_MAKE_VARS+=(RANLIB="$CI_RANLIB")
+    [[ $CI_LD ]] && ALL_MAKE_VARS+=(LD="$CI_LD")
+    [[ $ALL_LD_FLAGS ]] && ALL_MAKE_VARS+=(LDFLAGS="$ALL_LD_FLAGS")
+    ALL_MAKE_VARS+=(LIBS="$CI_LIBS")
+    ALL_MAKE_VARS+=($CI_MAKE_VARS)
+    # Build!
+    ci_spawn cd "$CI_SRCDIR"
+    local MY_MAKEFILE
+    for MY_MAKEFILE in $CI_LEGACY_MAKEFILES
+    do
+        ci_info "using makefile: $MY_MAKEFILE"
+        ci_spawn "$CI_MAKE" -f "$MY_MAKEFILE" \
+                            "${ALL_MAKE_FLAGS[@]}" \
+                            "${ALL_MAKE_VARS[@]}"
+        [[ $CI_NO_TEST ]] ||
+            ci_spawn "$CI_MAKE" -f "$MY_MAKEFILE" \
+                                "${ALL_MAKE_FLAGS[@]}" \
+                                "${ALL_MAKE_VARS[@]}" \
+                                test
+        [[ $CI_NO_CLEAN ]] ||
+            ci_spawn "$CI_MAKE" -f "$MY_MAKEFILE" \
+                                "${ALL_MAKE_FLAGS[@]}" \
+                                "${ALL_MAKE_VARS[@]}" \
+                                clean
+    done
+    ci_info "## END OF BUILD ##"
+}
+
+ci_init_legacy
+ci_trace_legacy
+[[ $# -eq 0 ]] || {
+    ci_info "note: this program accepts environment options only"
+    ci_err "unexpected command arguments: '$*'"
+}
+ci_build_legacy
diff --git a/compile b/compile
index 99e5052..df363c8 100755
--- a/compile
+++ b/compile
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 # Written by Tom Tromey <tromey@cygnus.com>.
 #
 # This program is free software; you can redistribute it and/or modify
@@ -53,7 +53,7 @@
 	  MINGW*)
 	    file_conv=mingw
 	    ;;
-	  CYGWIN*)
+	  CYGWIN* | MSYS*)
 	    file_conv=cygwin
 	    ;;
 	  *)
@@ -67,7 +67,7 @@
 	mingw/*)
 	  file=`cmd //C echo "$file " | sed -e 's/"\(.*\) " *$/\1/'`
 	  ;;
-	cygwin/*)
+	cygwin/* | msys/*)
 	  file=`cygpath -m "$file" || echo "$file"`
 	  ;;
 	wine/*)
diff --git a/config.guess b/config.guess
index 256083a..e81d3ae 100755
--- a/config.guess
+++ b/config.guess
@@ -1,8 +1,10 @@
 #! /bin/sh
 # Attempt to guess a canonical system name.
-#   Copyright 1992-2018 Free Software Foundation, Inc.
+#   Copyright 1992-2021 Free Software Foundation, Inc.
 
-timestamp='2018-03-08'
+# shellcheck disable=SC2006,SC2268 # see below for rationale
+
+timestamp='2021-06-03'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -27,11 +29,19 @@
 # Originally written by Per Bothner; maintained since 2000 by Ben Elliston.
 #
 # You can get the latest version of this script from:
-# https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess
+# https://git.savannah.gnu.org/cgit/config.git/plain/config.guess
 #
 # Please send patches to <config-patches@gnu.org>.
 
 
+# The "shellcheck disable" line above the timestamp inhibits complaints
+# about features and limitations of the classic Bourne shell that were
+# superseded or lifted in POSIX.  However, this script identifies a wide
+# variety of pre-POSIX systems that do not have POSIX shells at all, and
+# even some reasonably current systems (Solaris 10 as case-in-point) still
+# have a pre-POSIX /bin/sh.
+
+
 me=`echo "$0" | sed -e 's,.*/,,'`
 
 usage="\
@@ -50,7 +60,7 @@
 GNU config.guess ($timestamp)
 
 Originally written by Per Bothner.
-Copyright 1992-2018 Free Software Foundation, Inc.
+Copyright 1992-2021 Free Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@@ -84,7 +94,8 @@
   exit 1
 fi
 
-trap 'exit 1' 1 2 15
+# Just in case it came from the environment.
+GUESS=
 
 # CC_FOR_BUILD -- compiler used by this script. Note that the use of a
 # compiler to aid in system detection is discouraged as it requires
@@ -96,73 +107,90 @@
 
 # Portable tmp directory creation inspired by the Autoconf team.
 
-set_cc_for_build='
-trap "exitcode=\$?; (rm -f \$tmpfiles 2>/dev/null; rmdir \$tmp 2>/dev/null) && exit \$exitcode" 0 ;
-trap "rm -f \$tmpfiles 2>/dev/null; rmdir \$tmp 2>/dev/null; exit 1" 1 2 13 15 ;
-: ${TMPDIR=/tmp} ;
- { tmp=`(umask 077 && mktemp -d "$TMPDIR/cgXXXXXX") 2>/dev/null` && test -n "$tmp" && test -d "$tmp" ; } ||
- { test -n "$RANDOM" && tmp=$TMPDIR/cg$$-$RANDOM && (umask 077 && mkdir $tmp) ; } ||
- { tmp=$TMPDIR/cg-$$ && (umask 077 && mkdir $tmp) && echo "Warning: creating insecure temp directory" >&2 ; } ||
- { echo "$me: cannot create a temporary directory in $TMPDIR" >&2 ; exit 1 ; } ;
-dummy=$tmp/dummy ;
-tmpfiles="$dummy.c $dummy.o $dummy.rel $dummy" ;
-case $CC_FOR_BUILD,$HOST_CC,$CC in
- ,,)    echo "int x;" > "$dummy.c" ;
-	for c in cc gcc c89 c99 ; do
-	  if ($c -c -o "$dummy.o" "$dummy.c") >/dev/null 2>&1 ; then
-	     CC_FOR_BUILD="$c"; break ;
-	  fi ;
-	done ;
-	if test x"$CC_FOR_BUILD" = x ; then
-	  CC_FOR_BUILD=no_compiler_found ;
-	fi
-	;;
- ,,*)   CC_FOR_BUILD=$CC ;;
- ,*,*)  CC_FOR_BUILD=$HOST_CC ;;
-esac ; set_cc_for_build= ;'
+tmp=
+# shellcheck disable=SC2172
+trap 'test -z "$tmp" || rm -fr "$tmp"' 0 1 2 13 15
+
+set_cc_for_build() {
+    # prevent multiple calls if $tmp is already set
+    test "$tmp" && return 0
+    : "${TMPDIR=/tmp}"
+    # shellcheck disable=SC2039,SC3028
+    { tmp=`(umask 077 && mktemp -d "$TMPDIR/cgXXXXXX") 2>/dev/null` && test -n "$tmp" && test -d "$tmp" ; } ||
+	{ test -n "$RANDOM" && tmp=$TMPDIR/cg$$-$RANDOM && (umask 077 && mkdir "$tmp" 2>/dev/null) ; } ||
+	{ tmp=$TMPDIR/cg-$$ && (umask 077 && mkdir "$tmp" 2>/dev/null) && echo "Warning: creating insecure temp directory" >&2 ; } ||
+	{ echo "$me: cannot create a temporary directory in $TMPDIR" >&2 ; exit 1 ; }
+    dummy=$tmp/dummy
+    case ${CC_FOR_BUILD-},${HOST_CC-},${CC-} in
+	,,)    echo "int x;" > "$dummy.c"
+	       for driver in cc gcc c89 c99 ; do
+		   if ($driver -c -o "$dummy.o" "$dummy.c") >/dev/null 2>&1 ; then
+		       CC_FOR_BUILD=$driver
+		       break
+		   fi
+	       done
+	       if test x"$CC_FOR_BUILD" = x ; then
+		   CC_FOR_BUILD=no_compiler_found
+	       fi
+	       ;;
+	,,*)   CC_FOR_BUILD=$CC ;;
+	,*,*)  CC_FOR_BUILD=$HOST_CC ;;
+    esac
+}
 
 # This is needed to find uname on a Pyramid OSx when run in the BSD universe.
 # (ghazi@noc.rutgers.edu 1994-08-24)
-if (test -f /.attbin/uname) >/dev/null 2>&1 ; then
+if test -f /.attbin/uname ; then
 	PATH=$PATH:/.attbin ; export PATH
 fi
 
 UNAME_MACHINE=`(uname -m) 2>/dev/null` || UNAME_MACHINE=unknown
 UNAME_RELEASE=`(uname -r) 2>/dev/null` || UNAME_RELEASE=unknown
-UNAME_SYSTEM=`(uname -s) 2>/dev/null`  || UNAME_SYSTEM=unknown
+UNAME_SYSTEM=`(uname -s) 2>/dev/null` || UNAME_SYSTEM=unknown
 UNAME_VERSION=`(uname -v) 2>/dev/null` || UNAME_VERSION=unknown
 
-case "$UNAME_SYSTEM" in
+case $UNAME_SYSTEM in
 Linux|GNU|GNU/*)
-	# If the system lacks a compiler, then just pick glibc.
-	# We could probably try harder.
-	LIBC=gnu
+	LIBC=unknown
 
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	cat <<-EOF > "$dummy.c"
 	#include <features.h>
 	#if defined(__UCLIBC__)
 	LIBC=uclibc
 	#elif defined(__dietlibc__)
 	LIBC=dietlibc
-	#else
+	#elif defined(__GLIBC__)
 	LIBC=gnu
+	#else
+	#include <stdarg.h>
+	/* First heuristic to detect musl libc.  */
+	#ifdef __DEFINED_va_list
+	LIBC=musl
+	#endif
 	#endif
 	EOF
-	eval "`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^LIBC' | sed 's, ,,g'`"
+	cc_set_libc=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^LIBC' | sed 's, ,,g'`
+	eval "$cc_set_libc"
 
-	# If ldd exists, use it to detect musl libc.
-	if command -v ldd >/dev/null && \
-		ldd --version 2>&1 | grep -q ^musl
-	then
-	    LIBC=musl
+	# Second heuristic to detect musl libc.
+	if [ "$LIBC" = unknown ] &&
+	   command -v ldd >/dev/null &&
+	   ldd --version 2>&1 | grep -q ^musl; then
+		LIBC=musl
+	fi
+
+	# If the system lacks a compiler, then just pick glibc.
+	# We could probably try harder.
+	if [ "$LIBC" = unknown ]; then
+		LIBC=gnu
 	fi
 	;;
 esac
 
 # Note: order is significant - the case branches are not exclusive.
 
-case "$UNAME_MACHINE:$UNAME_SYSTEM:$UNAME_RELEASE:$UNAME_VERSION" in
+case $UNAME_MACHINE:$UNAME_SYSTEM:$UNAME_RELEASE:$UNAME_VERSION in
     *:NetBSD:*:*)
 	# NetBSD (nbsd) targets should (where applicable) match one or
 	# more of the tuples: *-*-netbsdelf*, *-*-netbsdaout*,
@@ -174,12 +202,12 @@
 	#
 	# Note: NetBSD doesn't particularly care about the vendor
 	# portion of the name.  We always set it to "unknown".
-	sysctl="sysctl -n hw.machine_arch"
 	UNAME_MACHINE_ARCH=`(uname -p 2>/dev/null || \
-	    "/sbin/$sysctl" 2>/dev/null || \
-	    "/usr/sbin/$sysctl" 2>/dev/null || \
+	    /sbin/sysctl -n hw.machine_arch 2>/dev/null || \
+	    /usr/sbin/sysctl -n hw.machine_arch 2>/dev/null || \
 	    echo unknown)`
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
+	    aarch64eb) machine=aarch64_be-unknown ;;
 	    armeb) machine=armeb-unknown ;;
 	    arm*) machine=arm-unknown ;;
 	    sh3el) machine=shl-unknown ;;
@@ -188,18 +216,18 @@
 	    earmv*)
 		arch=`echo "$UNAME_MACHINE_ARCH" | sed -e 's,^e\(armv[0-9]\).*$,\1,'`
 		endian=`echo "$UNAME_MACHINE_ARCH" | sed -ne 's,^.*\(eb\)$,\1,p'`
-		machine="${arch}${endian}"-unknown
+		machine=${arch}${endian}-unknown
 		;;
-	    *) machine="$UNAME_MACHINE_ARCH"-unknown ;;
+	    *) machine=$UNAME_MACHINE_ARCH-unknown ;;
 	esac
 	# The Operating System including object format, if it has switched
 	# to ELF recently (or will in the future) and ABI.
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
 	    earm*)
 		os=netbsdelf
 		;;
 	    arm*|i386|m68k|ns32k|sh3*|sparc|vax)
-		eval "$set_cc_for_build"
+		set_cc_for_build
 		if echo __ELF__ | $CC_FOR_BUILD -E - 2>/dev/null \
 			| grep -q __ELF__
 		then
@@ -215,7 +243,7 @@
 		;;
 	esac
 	# Determine ABI tags.
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
 	    earm*)
 		expr='s/^earmv[0-9]/-eabi/;s/eb$//'
 		abi=`echo "$UNAME_MACHINE_ARCH" | sed -e "$expr"`
@@ -226,7 +254,7 @@
 	# thus, need a distinct triplet. However, they do not need
 	# kernel version information, so it can be replaced with a
 	# suitable tag, in the style of linux-gnu.
-	case "$UNAME_VERSION" in
+	case $UNAME_VERSION in
 	    Debian*)
 		release='-gnu'
 		;;
@@ -237,45 +265,57 @@
 	# Since CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM:
 	# contains redundant information, the shorter form:
 	# CPU_TYPE-MANUFACTURER-OPERATING_SYSTEM is used.
-	echo "$machine-${os}${release}${abi}"
-	exit ;;
+	GUESS=$machine-${os}${release}${abi-}
+	;;
     *:Bitrig:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/Bitrig.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-bitrig"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-bitrig$UNAME_RELEASE
+	;;
     *:OpenBSD:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/OpenBSD.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-openbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-openbsd$UNAME_RELEASE
+	;;
+    *:SecBSD:*:*)
+	UNAME_MACHINE_ARCH=`arch | sed 's/SecBSD.//'`
+	GUESS=$UNAME_MACHINE_ARCH-unknown-secbsd$UNAME_RELEASE
+	;;
     *:LibertyBSD:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/^.*BSD\.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-libertybsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-libertybsd$UNAME_RELEASE
+	;;
     *:MidnightBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-midnightbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-midnightbsd$UNAME_RELEASE
+	;;
     *:ekkoBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-ekkobsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-ekkobsd$UNAME_RELEASE
+	;;
     *:SolidBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-solidbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-solidbsd$UNAME_RELEASE
+	;;
+    *:OS108:*:*)
+	GUESS=$UNAME_MACHINE-unknown-os108_$UNAME_RELEASE
+	;;
     macppc:MirBSD:*:*)
-	echo powerpc-unknown-mirbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-unknown-mirbsd$UNAME_RELEASE
+	;;
     *:MirBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-mirbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-mirbsd$UNAME_RELEASE
+	;;
     *:Sortix:*:*)
-	echo "$UNAME_MACHINE"-unknown-sortix
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-sortix
+	;;
+    *:Twizzler:*:*)
+	GUESS=$UNAME_MACHINE-unknown-twizzler
+	;;
     *:Redox:*:*)
-	echo "$UNAME_MACHINE"-unknown-redox
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-redox
+	;;
     mips:OSF1:*.*)
-        echo mips-dec-osf1
-        exit ;;
+	GUESS=mips-dec-osf1
+	;;
     alpha:OSF1:*:*)
+	# Reset EXIT trap before exiting to avoid spurious non-zero exit code.
+	trap '' 0
 	case $UNAME_RELEASE in
 	*4.0)
 		UNAME_RELEASE=`/usr/sbin/sizer -v | awk '{print $3}'`
@@ -289,7 +329,7 @@
 	# covers most systems running today.  This code pipes the CPU
 	# types through head -n 1, so we only detect the type of CPU 0.
 	ALPHA_CPU_TYPE=`/usr/sbin/psrinfo -v | sed -n -e 's/^  The alpha \(.*\) processor.*$/\1/p' | head -n 1`
-	case "$ALPHA_CPU_TYPE" in
+	case $ALPHA_CPU_TYPE in
 	    "EV4 (21064)")
 		UNAME_MACHINE=alpha ;;
 	    "EV4.5 (21064)")
@@ -326,75 +366,76 @@
 	# A Tn.n version is a released field test version.
 	# A Xn.n version is an unreleased experimental baselevel.
 	# 1.2 uses "1.2" for uname -r.
-	echo "$UNAME_MACHINE"-dec-osf"`echo "$UNAME_RELEASE" | sed -e 's/^[PVTX]//' | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`"
-	# Reset EXIT trap before exiting to avoid spurious non-zero exit code.
-	exitcode=$?
-	trap '' 0
-	exit $exitcode ;;
+	OSF_REL=`echo "$UNAME_RELEASE" | sed -e 's/^[PVTX]//' | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`
+	GUESS=$UNAME_MACHINE-dec-osf$OSF_REL
+	;;
     Amiga*:UNIX_System_V:4.0:*)
-	echo m68k-unknown-sysv4
-	exit ;;
+	GUESS=m68k-unknown-sysv4
+	;;
     *:[Aa]miga[Oo][Ss]:*:*)
-	echo "$UNAME_MACHINE"-unknown-amigaos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-amigaos
+	;;
     *:[Mm]orph[Oo][Ss]:*:*)
-	echo "$UNAME_MACHINE"-unknown-morphos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-morphos
+	;;
     *:OS/390:*:*)
-	echo i370-ibm-openedition
-	exit ;;
+	GUESS=i370-ibm-openedition
+	;;
     *:z/VM:*:*)
-	echo s390-ibm-zvmoe
-	exit ;;
+	GUESS=s390-ibm-zvmoe
+	;;
     *:OS400:*:*)
-	echo powerpc-ibm-os400
-	exit ;;
+	GUESS=powerpc-ibm-os400
+	;;
     arm:RISC*:1.[012]*:*|arm:riscix:1.[012]*:*)
-	echo arm-acorn-riscix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=arm-acorn-riscix$UNAME_RELEASE
+	;;
     arm*:riscos:*:*|arm*:RISCOS:*:*)
-	echo arm-unknown-riscos
-	exit ;;
+	GUESS=arm-unknown-riscos
+	;;
     SR2?01:HI-UX/MPP:*:* | SR8000:HI-UX/MPP:*:*)
-	echo hppa1.1-hitachi-hiuxmpp
-	exit ;;
+	GUESS=hppa1.1-hitachi-hiuxmpp
+	;;
     Pyramid*:OSx*:*:* | MIS*:OSx*:*:* | MIS*:SMP_DC-OSx*:*:*)
 	# akee@wpdis03.wpafb.af.mil (Earle F. Ake) contributed MIS and NILE.
-	if test "`(/bin/universe) 2>/dev/null`" = att ; then
-		echo pyramid-pyramid-sysv3
-	else
-		echo pyramid-pyramid-bsd
-	fi
-	exit ;;
+	case `(/bin/universe) 2>/dev/null` in
+	    att) GUESS=pyramid-pyramid-sysv3 ;;
+	    *)   GUESS=pyramid-pyramid-bsd   ;;
+	esac
+	;;
     NILE*:*:*:dcosx)
-	echo pyramid-pyramid-svr4
-	exit ;;
+	GUESS=pyramid-pyramid-svr4
+	;;
     DRS?6000:unix:4.0:6*)
-	echo sparc-icl-nx6
-	exit ;;
+	GUESS=sparc-icl-nx6
+	;;
     DRS?6000:UNIX_SV:4.2*:7* | DRS?6000:isis:4.2*:7*)
 	case `/usr/bin/uname -p` in
-	    sparc) echo sparc-icl-nx7; exit ;;
-	esac ;;
+	    sparc) GUESS=sparc-icl-nx7 ;;
+	esac
+	;;
     s390x:SunOS:*:*)
-	echo "$UNAME_MACHINE"-ibm-solaris2"`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=$UNAME_MACHINE-ibm-solaris2$SUN_REL
+	;;
     sun4H:SunOS:5.*:*)
-	echo sparc-hal-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-hal-solaris2$SUN_REL
+	;;
     sun4*:SunOS:5.*:* | tadpole*:SunOS:5.*:*)
-	echo sparc-sun-solaris2"`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-sun-solaris2$SUN_REL
+	;;
     i86pc:AuroraUX:5.*:* | i86xen:AuroraUX:5.*:*)
-	echo i386-pc-auroraux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=i386-pc-auroraux$UNAME_RELEASE
+	;;
     i86pc:SunOS:5.*:* | i86xen:SunOS:5.*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	SUN_ARCH=i386
 	# If there is a compiler, see if it is configured for 64-bit objects.
 	# Note that the Sun cc does not turn __LP64__ into 1 like gcc does.
 	# This test works for both compilers.
-	if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
 	    if (echo '#ifdef __amd64'; echo IS_64BIT_ARCH; echo '#endif') | \
 		(CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
 		grep IS_64BIT_ARCH >/dev/null
@@ -402,41 +443,44 @@
 		SUN_ARCH=x86_64
 	    fi
 	fi
-	echo "$SUN_ARCH"-pc-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=$SUN_ARCH-pc-solaris2$SUN_REL
+	;;
     sun4*:SunOS:6*:*)
 	# According to config.sub, this is the proper way to canonicalize
 	# SunOS6.  Hard to guess exactly what SunOS6 will be like, but
 	# it's likely to be more like Solaris than SunOS4.
-	echo sparc-sun-solaris3"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-sun-solaris3$SUN_REL
+	;;
     sun4*:SunOS:*:*)
-	case "`/usr/bin/arch -k`" in
+	case `/usr/bin/arch -k` in
 	    Series*|S4*)
 		UNAME_RELEASE=`uname -v`
 		;;
 	esac
 	# Japanese Language versions have a version number like `4.1.3-JL'.
-	echo sparc-sun-sunos"`echo "$UNAME_RELEASE"|sed -e 's/-/_/'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/-/_/'`
+	GUESS=sparc-sun-sunos$SUN_REL
+	;;
     sun3*:SunOS:*:*)
-	echo m68k-sun-sunos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-sun-sunos$UNAME_RELEASE
+	;;
     sun*:*:4.2BSD:*)
 	UNAME_RELEASE=`(sed 1q /etc/motd | awk '{print substr($5,1,3)}') 2>/dev/null`
 	test "x$UNAME_RELEASE" = x && UNAME_RELEASE=3
-	case "`/bin/arch`" in
+	case `/bin/arch` in
 	    sun3)
-		echo m68k-sun-sunos"$UNAME_RELEASE"
+		GUESS=m68k-sun-sunos$UNAME_RELEASE
 		;;
 	    sun4)
-		echo sparc-sun-sunos"$UNAME_RELEASE"
+		GUESS=sparc-sun-sunos$UNAME_RELEASE
 		;;
 	esac
-	exit ;;
+	;;
     aushp:SunOS:*:*)
-	echo sparc-auspex-sunos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-auspex-sunos$UNAME_RELEASE
+	;;
     # The situation for MiNT is a little confusing.  The machine name
     # can be virtually everything (everything which is not
     # "atarist" or "atariste" at least should have a processor
@@ -446,43 +490,43 @@
     # MiNT.  But MiNT is downward compatible to TOS, so this should
     # be no problem.
     atarist[e]:*MiNT:*:* | atarist[e]:*mint:*:* | atarist[e]:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     atari*:*MiNT:*:* | atari*:*mint:*:* | atarist[e]:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     *falcon*:*MiNT:*:* | *falcon*:*mint:*:* | *falcon*:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     milan*:*MiNT:*:* | milan*:*mint:*:* | *milan*:*TOS:*:*)
-	echo m68k-milan-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-milan-mint$UNAME_RELEASE
+	;;
     hades*:*MiNT:*:* | hades*:*mint:*:* | *hades*:*TOS:*:*)
-	echo m68k-hades-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-hades-mint$UNAME_RELEASE
+	;;
     *:*MiNT:*:* | *:*mint:*:* | *:*TOS:*:*)
-	echo m68k-unknown-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-unknown-mint$UNAME_RELEASE
+	;;
     m68k:machten:*:*)
-	echo m68k-apple-machten"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-apple-machten$UNAME_RELEASE
+	;;
     powerpc:machten:*:*)
-	echo powerpc-apple-machten"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-apple-machten$UNAME_RELEASE
+	;;
     RISC*:Mach:*:*)
-	echo mips-dec-mach_bsd4.3
-	exit ;;
+	GUESS=mips-dec-mach_bsd4.3
+	;;
     RISC*:ULTRIX:*:*)
-	echo mips-dec-ultrix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-dec-ultrix$UNAME_RELEASE
+	;;
     VAX*:ULTRIX*:*:*)
-	echo vax-dec-ultrix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=vax-dec-ultrix$UNAME_RELEASE
+	;;
     2020:CLIX:*:* | 2430:CLIX:*:*)
-	echo clipper-intergraph-clix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=clipper-intergraph-clix$UNAME_RELEASE
+	;;
     mips:*:*:UMIPS | mips:*:*:RISCos)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	sed 's/^	//' << EOF > "$dummy.c"
 #ifdef __cplusplus
 #include <stdio.h>  /* for printf() prototype */
@@ -508,78 +552,79 @@
 	  dummyarg=`echo "$UNAME_RELEASE" | sed -n 's/\([0-9]*\).*/\1/p'` &&
 	  SYSTEM_NAME=`"$dummy" "$dummyarg"` &&
 	    { echo "$SYSTEM_NAME"; exit; }
-	echo mips-mips-riscos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-mips-riscos$UNAME_RELEASE
+	;;
     Motorola:PowerMAX_OS:*:*)
-	echo powerpc-motorola-powermax
-	exit ;;
+	GUESS=powerpc-motorola-powermax
+	;;
     Motorola:*:4.3:PL8-*)
-	echo powerpc-harris-powermax
-	exit ;;
+	GUESS=powerpc-harris-powermax
+	;;
     Night_Hawk:*:*:PowerMAX_OS | Synergy:PowerMAX_OS:*:*)
-	echo powerpc-harris-powermax
-	exit ;;
+	GUESS=powerpc-harris-powermax
+	;;
     Night_Hawk:Power_UNIX:*:*)
-	echo powerpc-harris-powerunix
-	exit ;;
+	GUESS=powerpc-harris-powerunix
+	;;
     m88k:CX/UX:7*:*)
-	echo m88k-harris-cxux7
-	exit ;;
+	GUESS=m88k-harris-cxux7
+	;;
     m88k:*:4*:R4*)
-	echo m88k-motorola-sysv4
-	exit ;;
+	GUESS=m88k-motorola-sysv4
+	;;
     m88k:*:3*:R3*)
-	echo m88k-motorola-sysv3
-	exit ;;
+	GUESS=m88k-motorola-sysv3
+	;;
     AViiON:dgux:*:*)
 	# DG/UX returns AViiON for all architectures
 	UNAME_PROCESSOR=`/usr/bin/uname -p`
-	if [ "$UNAME_PROCESSOR" = mc88100 ] || [ "$UNAME_PROCESSOR" = mc88110 ]
+	if test "$UNAME_PROCESSOR" = mc88100 || test "$UNAME_PROCESSOR" = mc88110
 	then
-	    if [ "$TARGET_BINARY_INTERFACE"x = m88kdguxelfx ] || \
-	       [ "$TARGET_BINARY_INTERFACE"x = x ]
+	    if test "$TARGET_BINARY_INTERFACE"x = m88kdguxelfx || \
+	       test "$TARGET_BINARY_INTERFACE"x = x
 	    then
-		echo m88k-dg-dgux"$UNAME_RELEASE"
+		GUESS=m88k-dg-dgux$UNAME_RELEASE
 	    else
-		echo m88k-dg-dguxbcs"$UNAME_RELEASE"
+		GUESS=m88k-dg-dguxbcs$UNAME_RELEASE
 	    fi
 	else
-	    echo i586-dg-dgux"$UNAME_RELEASE"
+	    GUESS=i586-dg-dgux$UNAME_RELEASE
 	fi
-	exit ;;
+	;;
     M88*:DolphinOS:*:*)	# DolphinOS (SVR3)
-	echo m88k-dolphin-sysv3
-	exit ;;
+	GUESS=m88k-dolphin-sysv3
+	;;
     M88*:*:R3*:*)
 	# Delta 88k system running SVR3
-	echo m88k-motorola-sysv3
-	exit ;;
+	GUESS=m88k-motorola-sysv3
+	;;
     XD88*:*:*:*) # Tektronix XD88 system running UTekV (SVR3)
-	echo m88k-tektronix-sysv3
-	exit ;;
+	GUESS=m88k-tektronix-sysv3
+	;;
     Tek43[0-9][0-9]:UTek:*:*) # Tektronix 4300 system running UTek (BSD)
-	echo m68k-tektronix-bsd
-	exit ;;
+	GUESS=m68k-tektronix-bsd
+	;;
     *:IRIX*:*:*)
-	echo mips-sgi-irix"`echo "$UNAME_RELEASE"|sed -e 's/-/_/g'`"
-	exit ;;
+	IRIX_REL=`echo "$UNAME_RELEASE" | sed -e 's/-/_/g'`
+	GUESS=mips-sgi-irix$IRIX_REL
+	;;
     ????????:AIX?:[12].1:2)   # AIX 2.2.1 or AIX 2.1.1 is RT/PC AIX.
-	echo romp-ibm-aix     # uname -m gives an 8 hex-code CPU id
-	exit ;;               # Note that: echo "'`uname -s`'" gives 'AIX '
+	GUESS=romp-ibm-aix    # uname -m gives an 8 hex-code CPU id
+	;;                    # Note that: echo "'`uname -s`'" gives 'AIX '
     i*86:AIX:*:*)
-	echo i386-ibm-aix
-	exit ;;
+	GUESS=i386-ibm-aix
+	;;
     ia64:AIX:*:*)
-	if [ -x /usr/bin/oslevel ] ; then
+	if test -x /usr/bin/oslevel ; then
 		IBM_REV=`/usr/bin/oslevel`
 	else
-		IBM_REV="$UNAME_VERSION.$UNAME_RELEASE"
+		IBM_REV=$UNAME_VERSION.$UNAME_RELEASE
 	fi
-	echo "$UNAME_MACHINE"-ibm-aix"$IBM_REV"
-	exit ;;
+	GUESS=$UNAME_MACHINE-ibm-aix$IBM_REV
+	;;
     *:AIX:2:3)
 	if grep bos325 /usr/include/stdio.h >/dev/null 2>&1; then
-		eval "$set_cc_for_build"
+		set_cc_for_build
 		sed 's/^		//' << EOF > "$dummy.c"
 		#include <sys/systemcfg.h>
 
@@ -593,16 +638,16 @@
 EOF
 		if $CC_FOR_BUILD -o "$dummy" "$dummy.c" && SYSTEM_NAME=`"$dummy"`
 		then
-			echo "$SYSTEM_NAME"
+			GUESS=$SYSTEM_NAME
 		else
-			echo rs6000-ibm-aix3.2.5
+			GUESS=rs6000-ibm-aix3.2.5
 		fi
 	elif grep bos324 /usr/include/stdio.h >/dev/null 2>&1; then
-		echo rs6000-ibm-aix3.2.4
+		GUESS=rs6000-ibm-aix3.2.4
 	else
-		echo rs6000-ibm-aix3.2
+		GUESS=rs6000-ibm-aix3.2
 	fi
-	exit ;;
+	;;
     *:AIX:*:[4567])
 	IBM_CPU_ID=`/usr/sbin/lsdev -C -c processor -S available | sed 1q | awk '{ print $1 }'`
 	if /usr/sbin/lsattr -El "$IBM_CPU_ID" | grep ' POWER' >/dev/null 2>&1; then
@@ -610,57 +655,57 @@
 	else
 		IBM_ARCH=powerpc
 	fi
-	if [ -x /usr/bin/lslpp ] ; then
-		IBM_REV=`/usr/bin/lslpp -Lqc bos.rte.libc |
+	if test -x /usr/bin/lslpp ; then
+		IBM_REV=`/usr/bin/lslpp -Lqc bos.rte.libc | \
 			   awk -F: '{ print $3 }' | sed s/[0-9]*$/0/`
 	else
-		IBM_REV="$UNAME_VERSION.$UNAME_RELEASE"
+		IBM_REV=$UNAME_VERSION.$UNAME_RELEASE
 	fi
-	echo "$IBM_ARCH"-ibm-aix"$IBM_REV"
-	exit ;;
+	GUESS=$IBM_ARCH-ibm-aix$IBM_REV
+	;;
     *:AIX:*:*)
-	echo rs6000-ibm-aix
-	exit ;;
+	GUESS=rs6000-ibm-aix
+	;;
     ibmrt:4.4BSD:*|romp-ibm:4.4BSD:*)
-	echo romp-ibm-bsd4.4
-	exit ;;
+	GUESS=romp-ibm-bsd4.4
+	;;
     ibmrt:*BSD:*|romp-ibm:BSD:*)            # covers RT/PC BSD and
-	echo romp-ibm-bsd"$UNAME_RELEASE"   # 4.3 with uname added to
-	exit ;;                             # report: romp-ibm BSD 4.3
+	GUESS=romp-ibm-bsd$UNAME_RELEASE    # 4.3 with uname added to
+	;;                                  # report: romp-ibm BSD 4.3
     *:BOSX:*:*)
-	echo rs6000-bull-bosx
-	exit ;;
+	GUESS=rs6000-bull-bosx
+	;;
     DPX/2?00:B.O.S.:*:*)
-	echo m68k-bull-sysv3
-	exit ;;
+	GUESS=m68k-bull-sysv3
+	;;
     9000/[34]??:4.3bsd:1.*:*)
-	echo m68k-hp-bsd
-	exit ;;
+	GUESS=m68k-hp-bsd
+	;;
     hp300:4.4BSD:*:* | 9000/[34]??:4.3bsd:2.*:*)
-	echo m68k-hp-bsd4.4
-	exit ;;
+	GUESS=m68k-hp-bsd4.4
+	;;
     9000/[34678]??:HP-UX:*:*)
-	HPUX_REV=`echo "$UNAME_RELEASE"|sed -e 's/[^.]*.[0B]*//'`
-	case "$UNAME_MACHINE" in
+	HPUX_REV=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*.[0B]*//'`
+	case $UNAME_MACHINE in
 	    9000/31?)            HP_ARCH=m68000 ;;
 	    9000/[34]??)         HP_ARCH=m68k ;;
 	    9000/[678][0-9][0-9])
-		if [ -x /usr/bin/getconf ]; then
+		if test -x /usr/bin/getconf; then
 		    sc_cpu_version=`/usr/bin/getconf SC_CPU_VERSION 2>/dev/null`
 		    sc_kernel_bits=`/usr/bin/getconf SC_KERNEL_BITS 2>/dev/null`
-		    case "$sc_cpu_version" in
+		    case $sc_cpu_version in
 		      523) HP_ARCH=hppa1.0 ;; # CPU_PA_RISC1_0
 		      528) HP_ARCH=hppa1.1 ;; # CPU_PA_RISC1_1
 		      532)                      # CPU_PA_RISC2_0
-			case "$sc_kernel_bits" in
+			case $sc_kernel_bits in
 			  32) HP_ARCH=hppa2.0n ;;
 			  64) HP_ARCH=hppa2.0w ;;
 			  '') HP_ARCH=hppa2.0 ;;   # HP-UX 10.20
 			esac ;;
 		    esac
 		fi
-		if [ "$HP_ARCH" = "" ]; then
-		    eval "$set_cc_for_build"
+		if test "$HP_ARCH" = ""; then
+		    set_cc_for_build
 		    sed 's/^		//' << EOF > "$dummy.c"
 
 		#define _HPUX_SOURCE
@@ -698,9 +743,9 @@
 		    test -z "$HP_ARCH" && HP_ARCH=hppa
 		fi ;;
 	esac
-	if [ "$HP_ARCH" = hppa2.0w ]
+	if test "$HP_ARCH" = hppa2.0w
 	then
-	    eval "$set_cc_for_build"
+	    set_cc_for_build
 
 	    # hppa2.0w-hp-hpux* has a 64-bit kernel and a compiler generating
 	    # 32-bit code.  hppa64-hp-hpux* has the same kernel and a compiler
@@ -719,14 +764,14 @@
 		HP_ARCH=hppa64
 	    fi
 	fi
-	echo "$HP_ARCH"-hp-hpux"$HPUX_REV"
-	exit ;;
+	GUESS=$HP_ARCH-hp-hpux$HPUX_REV
+	;;
     ia64:HP-UX:*:*)
-	HPUX_REV=`echo "$UNAME_RELEASE"|sed -e 's/[^.]*.[0B]*//'`
-	echo ia64-hp-hpux"$HPUX_REV"
-	exit ;;
+	HPUX_REV=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*.[0B]*//'`
+	GUESS=ia64-hp-hpux$HPUX_REV
+	;;
     3050*:HI-UX:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	sed 's/^	//' << EOF > "$dummy.c"
 	#include <unistd.h>
 	int
@@ -754,36 +799,36 @@
 EOF
 	$CC_FOR_BUILD -o "$dummy" "$dummy.c" && SYSTEM_NAME=`"$dummy"` &&
 		{ echo "$SYSTEM_NAME"; exit; }
-	echo unknown-hitachi-hiuxwe2
-	exit ;;
+	GUESS=unknown-hitachi-hiuxwe2
+	;;
     9000/7??:4.3bsd:*:* | 9000/8?[79]:4.3bsd:*:*)
-	echo hppa1.1-hp-bsd
-	exit ;;
+	GUESS=hppa1.1-hp-bsd
+	;;
     9000/8??:4.3bsd:*:*)
-	echo hppa1.0-hp-bsd
-	exit ;;
+	GUESS=hppa1.0-hp-bsd
+	;;
     *9??*:MPE/iX:*:* | *3000*:MPE/iX:*:*)
-	echo hppa1.0-hp-mpeix
-	exit ;;
+	GUESS=hppa1.0-hp-mpeix
+	;;
     hp7??:OSF1:*:* | hp8?[79]:OSF1:*:*)
-	echo hppa1.1-hp-osf
-	exit ;;
+	GUESS=hppa1.1-hp-osf
+	;;
     hp8??:OSF1:*:*)
-	echo hppa1.0-hp-osf
-	exit ;;
+	GUESS=hppa1.0-hp-osf
+	;;
     i*86:OSF1:*:*)
-	if [ -x /usr/sbin/sysversion ] ; then
-	    echo "$UNAME_MACHINE"-unknown-osf1mk
+	if test -x /usr/sbin/sysversion ; then
+	    GUESS=$UNAME_MACHINE-unknown-osf1mk
 	else
-	    echo "$UNAME_MACHINE"-unknown-osf1
+	    GUESS=$UNAME_MACHINE-unknown-osf1
 	fi
-	exit ;;
+	;;
     parisc*:Lites*:*:*)
-	echo hppa1.1-hp-lites
-	exit ;;
+	GUESS=hppa1.1-hp-lites
+	;;
     C1*:ConvexOS:*:* | convex:ConvexOS:C1*:*)
-	echo c1-convex-bsd
-	exit ;;
+	GUESS=c1-convex-bsd
+	;;
     C2*:ConvexOS:*:* | convex:ConvexOS:C2*:*)
 	if getsysinfo -f scalar_acc
 	then echo c32-convex-bsd
@@ -791,17 +836,18 @@
 	fi
 	exit ;;
     C34*:ConvexOS:*:* | convex:ConvexOS:C34*:*)
-	echo c34-convex-bsd
-	exit ;;
+	GUESS=c34-convex-bsd
+	;;
     C38*:ConvexOS:*:* | convex:ConvexOS:C38*:*)
-	echo c38-convex-bsd
-	exit ;;
+	GUESS=c38-convex-bsd
+	;;
     C4*:ConvexOS:*:* | convex:ConvexOS:C4*:*)
-	echo c4-convex-bsd
-	exit ;;
+	GUESS=c4-convex-bsd
+	;;
     CRAY*Y-MP:*:*:*)
-	echo ymp-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=ymp-cray-unicos$CRAY_REL
+	;;
     CRAY*[A-Z]90:*:*:*)
 	echo "$UNAME_MACHINE"-cray-unicos"$UNAME_RELEASE" \
 	| sed -e 's/CRAY.*\([A-Z]90\)/\1/' \
@@ -809,103 +855,126 @@
 	      -e 's/\.[^.]*$/.X/'
 	exit ;;
     CRAY*TS:*:*:*)
-	echo t90-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=t90-cray-unicos$CRAY_REL
+	;;
     CRAY*T3E:*:*:*)
-	echo alphaev5-cray-unicosmk"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=alphaev5-cray-unicosmk$CRAY_REL
+	;;
     CRAY*SV1:*:*:*)
-	echo sv1-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=sv1-cray-unicos$CRAY_REL
+	;;
     *:UNICOS/mp:*:*)
-	echo craynv-cray-unicosmp"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=craynv-cray-unicosmp$CRAY_REL
+	;;
     F30[01]:UNIX_System_V:*:* | F700:UNIX_System_V:*:*)
 	FUJITSU_PROC=`uname -m | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`
 	FUJITSU_SYS=`uname -p | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/\///'`
 	FUJITSU_REL=`echo "$UNAME_RELEASE" | sed -e 's/ /_/'`
-	echo "${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
-	exit ;;
+	GUESS=${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}
+	;;
     5000:UNIX_System_V:4.*:*)
 	FUJITSU_SYS=`uname -p | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/\///'`
 	FUJITSU_REL=`echo "$UNAME_RELEASE" | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/ /_/'`
-	echo "sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
-	exit ;;
+	GUESS=sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}
+	;;
     i*86:BSD/386:*:* | i*86:BSD/OS:*:* | *:Ascend\ Embedded/OS:*:*)
-	echo "$UNAME_MACHINE"-pc-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-bsdi$UNAME_RELEASE
+	;;
     sparc*:BSD/OS:*:*)
-	echo sparc-unknown-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-unknown-bsdi$UNAME_RELEASE
+	;;
     *:BSD/OS:*:*)
-	echo "$UNAME_MACHINE"-unknown-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-bsdi$UNAME_RELEASE
+	;;
+    arm:FreeBSD:*:*)
+	UNAME_PROCESSOR=`uname -p`
+	set_cc_for_build
+	if echo __ARM_PCS_VFP | $CC_FOR_BUILD -E - 2>/dev/null \
+	    | grep -q __ARM_PCS_VFP
+	then
+	    FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	    GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL-gnueabi
+	else
+	    FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	    GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL-gnueabihf
+	fi
+	;;
     *:FreeBSD:*:*)
 	UNAME_PROCESSOR=`/usr/bin/uname -p`
-	case "$UNAME_PROCESSOR" in
+	case $UNAME_PROCESSOR in
 	    amd64)
 		UNAME_PROCESSOR=x86_64 ;;
 	    i386)
 		UNAME_PROCESSOR=i586 ;;
 	esac
-	echo "$UNAME_PROCESSOR"-unknown-freebsd"`echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`"
-	exit ;;
+	FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL
+	;;
     i*:CYGWIN*:*)
-	echo "$UNAME_MACHINE"-pc-cygwin
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-cygwin
+	;;
     *:MINGW64*:*)
-	echo "$UNAME_MACHINE"-pc-mingw64
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-mingw64
+	;;
     *:MINGW*:*)
-	echo "$UNAME_MACHINE"-pc-mingw32
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-mingw32
+	;;
     *:MSYS*:*)
-	echo "$UNAME_MACHINE"-pc-msys
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-msys
+	;;
     i*:PW*:*)
-	echo "$UNAME_MACHINE"-pc-pw32
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-pw32
+	;;
     *:Interix*:*)
-	case "$UNAME_MACHINE" in
+	case $UNAME_MACHINE in
 	    x86)
-		echo i586-pc-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=i586-pc-interix$UNAME_RELEASE
+		;;
 	    authenticamd | genuineintel | EM64T)
-		echo x86_64-unknown-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=x86_64-unknown-interix$UNAME_RELEASE
+		;;
 	    IA64)
-		echo ia64-unknown-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=ia64-unknown-interix$UNAME_RELEASE
+		;;
 	esac ;;
     i*:UWIN*:*)
-	echo "$UNAME_MACHINE"-pc-uwin
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-uwin
+	;;
     amd64:CYGWIN*:*:* | x86_64:CYGWIN*:*:*)
-	echo x86_64-unknown-cygwin
-	exit ;;
+	GUESS=x86_64-pc-cygwin
+	;;
     prep*:SunOS:5.*:*)
-	echo powerpcle-unknown-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=powerpcle-unknown-solaris2$SUN_REL
+	;;
     *:GNU:*:*)
 	# the GNU system
-	echo "`echo "$UNAME_MACHINE"|sed -e 's,[-/].*$,,'`-unknown-$LIBC`echo "$UNAME_RELEASE"|sed -e 's,/.*$,,'`"
-	exit ;;
+	GNU_ARCH=`echo "$UNAME_MACHINE" | sed -e 's,[-/].*$,,'`
+	GNU_REL=`echo "$UNAME_RELEASE" | sed -e 's,/.*$,,'`
+	GUESS=$GNU_ARCH-unknown-$LIBC$GNU_REL
+	;;
     *:GNU/*:*:*)
 	# other systems with GNU libc and userland
-	echo "$UNAME_MACHINE-unknown-`echo "$UNAME_SYSTEM" | sed 's,^[^/]*/,,' | tr "[:upper:]" "[:lower:]"``echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`-$LIBC"
-	exit ;;
-    i*86:Minix:*:*)
-	echo "$UNAME_MACHINE"-pc-minix
-	exit ;;
+	GNU_SYS=`echo "$UNAME_SYSTEM" | sed 's,^[^/]*/,,' | tr "[:upper:]" "[:lower:]"`
+	GNU_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_MACHINE-unknown-$GNU_SYS$GNU_REL-$LIBC
+	;;
+    *:Minix:*:*)
+	GUESS=$UNAME_MACHINE-unknown-minix
+	;;
     aarch64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     aarch64_be:Linux:*:*)
 	UNAME_MACHINE=aarch64_be
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     alpha:Linux:*:*)
-	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' < /proc/cpuinfo` in
+	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' /proc/cpuinfo 2>/dev/null` in
 	  EV5)   UNAME_MACHINE=alphaev5 ;;
 	  EV56)  UNAME_MACHINE=alphaev56 ;;
 	  PCA56) UNAME_MACHINE=alphapca56 ;;
@@ -916,183 +985,225 @@
 	esac
 	objdump --private-headers /bin/sh | grep -q ld.so.1
 	if test "$?" = 0 ; then LIBC=gnulibc1 ; fi
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
-    arc:Linux:*:* | arceb:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
+    arc:Linux:*:* | arceb:Linux:*:* | arc32:Linux:*:* | arc64:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     arm*:Linux:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	if echo __ARM_EABI__ | $CC_FOR_BUILD -E - 2>/dev/null \
 	    | grep -q __ARM_EABI__
 	then
-	    echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
+	    GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
 	else
 	    if echo __ARM_PCS_VFP | $CC_FOR_BUILD -E - 2>/dev/null \
 		| grep -q __ARM_PCS_VFP
 	    then
-		echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"eabi
+		GUESS=$UNAME_MACHINE-unknown-linux-${LIBC}eabi
 	    else
-		echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"eabihf
+		GUESS=$UNAME_MACHINE-unknown-linux-${LIBC}eabihf
 	    fi
 	fi
-	exit ;;
+	;;
     avr32*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     cris:Linux:*:*)
-	echo "$UNAME_MACHINE"-axis-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-axis-linux-$LIBC
+	;;
     crisv32:Linux:*:*)
-	echo "$UNAME_MACHINE"-axis-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-axis-linux-$LIBC
+	;;
     e2k:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     frv:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     hexagon:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     i*86:Linux:*:*)
-	echo "$UNAME_MACHINE"-pc-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-linux-$LIBC
+	;;
     ia64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     k1om:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
+    loongarch32:Linux:*:* | loongarch64:Linux:*:* | loongarchx32:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     m32r*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     m68*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     mips:Linux:*:* | mips64:Linux:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
+	IS_GLIBC=0
+	test x"${LIBC}" = xgnu && IS_GLIBC=1
 	sed 's/^	//' << EOF > "$dummy.c"
 	#undef CPU
-	#undef ${UNAME_MACHINE}
-	#undef ${UNAME_MACHINE}el
+	#undef mips
+	#undef mipsel
+	#undef mips64
+	#undef mips64el
+	#if ${IS_GLIBC} && defined(_ABI64)
+	LIBCABI=gnuabi64
+	#else
+	#if ${IS_GLIBC} && defined(_ABIN32)
+	LIBCABI=gnuabin32
+	#else
+	LIBCABI=${LIBC}
+	#endif
+	#endif
+
+	#if ${IS_GLIBC} && defined(__mips64) && defined(__mips_isa_rev) && __mips_isa_rev>=6
+	CPU=mipsisa64r6
+	#else
+	#if ${IS_GLIBC} && !defined(__mips64) && defined(__mips_isa_rev) && __mips_isa_rev>=6
+	CPU=mipsisa32r6
+	#else
+	#if defined(__mips64)
+	CPU=mips64
+	#else
+	CPU=mips
+	#endif
+	#endif
+	#endif
+
 	#if defined(__MIPSEL__) || defined(__MIPSEL) || defined(_MIPSEL) || defined(MIPSEL)
-	CPU=${UNAME_MACHINE}el
+	MIPS_ENDIAN=el
 	#else
 	#if defined(__MIPSEB__) || defined(__MIPSEB) || defined(_MIPSEB) || defined(MIPSEB)
-	CPU=${UNAME_MACHINE}
+	MIPS_ENDIAN=
 	#else
-	CPU=
+	MIPS_ENDIAN=
 	#endif
 	#endif
 EOF
-	eval "`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^CPU'`"
-	test "x$CPU" != x && { echo "$CPU-unknown-linux-$LIBC"; exit; }
+	cc_set_vars=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^CPU\|^MIPS_ENDIAN\|^LIBCABI'`
+	eval "$cc_set_vars"
+	test "x$CPU" != x && { echo "$CPU${MIPS_ENDIAN}-unknown-linux-$LIBCABI"; exit; }
 	;;
     mips64el:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     openrisc*:Linux:*:*)
-	echo or1k-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=or1k-unknown-linux-$LIBC
+	;;
     or32:Linux:*:* | or1k*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     padre:Linux:*:*)
-	echo sparc-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=sparc-unknown-linux-$LIBC
+	;;
     parisc64:Linux:*:* | hppa64:Linux:*:*)
-	echo hppa64-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=hppa64-unknown-linux-$LIBC
+	;;
     parisc:Linux:*:* | hppa:Linux:*:*)
 	# Look for CPU level
 	case `grep '^cpu[^a-z]*:' /proc/cpuinfo 2>/dev/null | cut -d' ' -f2` in
-	  PA7*) echo hppa1.1-unknown-linux-"$LIBC" ;;
-	  PA8*) echo hppa2.0-unknown-linux-"$LIBC" ;;
-	  *)    echo hppa-unknown-linux-"$LIBC" ;;
+	  PA7*) GUESS=hppa1.1-unknown-linux-$LIBC ;;
+	  PA8*) GUESS=hppa2.0-unknown-linux-$LIBC ;;
+	  *)    GUESS=hppa-unknown-linux-$LIBC ;;
 	esac
-	exit ;;
+	;;
     ppc64:Linux:*:*)
-	echo powerpc64-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc64-unknown-linux-$LIBC
+	;;
     ppc:Linux:*:*)
-	echo powerpc-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc-unknown-linux-$LIBC
+	;;
     ppc64le:Linux:*:*)
-	echo powerpc64le-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc64le-unknown-linux-$LIBC
+	;;
     ppcle:Linux:*:*)
-	echo powerpcle-unknown-linux-"$LIBC"
-	exit ;;
-    riscv32:Linux:*:* | riscv64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpcle-unknown-linux-$LIBC
+	;;
+    riscv32:Linux:*:* | riscv32be:Linux:*:* | riscv64:Linux:*:* | riscv64be:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     s390:Linux:*:* | s390x:Linux:*:*)
-	echo "$UNAME_MACHINE"-ibm-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-ibm-linux-$LIBC
+	;;
     sh64*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     sh*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     sparc:Linux:*:* | sparc64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     tile*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     vax:Linux:*:*)
-	echo "$UNAME_MACHINE"-dec-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-dec-linux-$LIBC
+	;;
     x86_64:Linux:*:*)
-	echo "$UNAME_MACHINE"-pc-linux-"$LIBC"
-	exit ;;
+	set_cc_for_build
+	LIBCABI=$LIBC
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
+	    if (echo '#ifdef __ILP32__'; echo IS_X32; echo '#endif') | \
+		(CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		grep IS_X32 >/dev/null
+	    then
+		LIBCABI=${LIBC}x32
+	    fi
+	fi
+	GUESS=$UNAME_MACHINE-pc-linux-$LIBCABI
+	;;
     xtensa*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     i*86:DYNIX/ptx:4*:*)
 	# ptx 4.0 does uname -s correctly, with DYNIX/ptx in there.
 	# earlier versions are messed up and put the nodename in both
 	# sysname and nodename.
-	echo i386-sequent-sysv4
-	exit ;;
+	GUESS=i386-sequent-sysv4
+	;;
     i*86:UNIX_SV:4.2MP:2.*)
 	# Unixware is an offshoot of SVR4, but it has its own version
 	# number series starting with 2...
 	# I am not positive that other SVR4 systems won't match this,
 	# I just have to hope.  -- rms.
 	# Use sysv4.2uw... so that sysv4* matches it.
-	echo "$UNAME_MACHINE"-pc-sysv4.2uw"$UNAME_VERSION"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-sysv4.2uw$UNAME_VERSION
+	;;
     i*86:OS/2:*:*)
 	# If we were able to find `uname', then EMX Unix compatibility
 	# is probably installed.
-	echo "$UNAME_MACHINE"-pc-os2-emx
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-os2-emx
+	;;
     i*86:XTS-300:*:STOP)
-	echo "$UNAME_MACHINE"-unknown-stop
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-stop
+	;;
     i*86:atheos:*:*)
-	echo "$UNAME_MACHINE"-unknown-atheos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-atheos
+	;;
     i*86:syllable:*:*)
-	echo "$UNAME_MACHINE"-pc-syllable
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-syllable
+	;;
     i*86:LynxOS:2.*:* | i*86:LynxOS:3.[01]*:* | i*86:LynxOS:4.[02]*:*)
-	echo i386-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=i386-unknown-lynxos$UNAME_RELEASE
+	;;
     i*86:*DOS:*:*)
-	echo "$UNAME_MACHINE"-pc-msdosdjgpp
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-msdosdjgpp
+	;;
     i*86:*:4.*:*)
 	UNAME_REL=`echo "$UNAME_RELEASE" | sed 's/\/MP$//'`
 	if grep Novell /usr/include/link.h >/dev/null 2>/dev/null; then
-		echo "$UNAME_MACHINE"-univel-sysv"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-univel-sysv$UNAME_REL
 	else
-		echo "$UNAME_MACHINE"-pc-sysv"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-sysv$UNAME_REL
 	fi
-	exit ;;
+	;;
     i*86:*:5:[678]*)
 	# UnixWare 7.x, OpenUNIX and OpenServer 6.
 	case `/bin/uname -X | grep "^Machine"` in
@@ -1100,12 +1211,12 @@
 	    *Pentium)	     UNAME_MACHINE=i586 ;;
 	    *Pent*|*Celeron) UNAME_MACHINE=i686 ;;
 	esac
-	echo "$UNAME_MACHINE-unknown-sysv${UNAME_RELEASE}${UNAME_SYSTEM}{$UNAME_VERSION}"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-sysv${UNAME_RELEASE}${UNAME_SYSTEM}${UNAME_VERSION}
+	;;
     i*86:*:3.2:*)
 	if test -f /usr/options/cb.name; then
 		UNAME_REL=`sed -n 's/.*Version //p' </usr/options/cb.name`
-		echo "$UNAME_MACHINE"-pc-isc"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-isc$UNAME_REL
 	elif /bin/uname -X 2>/dev/null >/dev/null ; then
 		UNAME_REL=`(/bin/uname -X|grep Release|sed -e 's/.*= //')`
 		(/bin/uname -X|grep i80486 >/dev/null) && UNAME_MACHINE=i486
@@ -1115,11 +1226,11 @@
 			&& UNAME_MACHINE=i686
 		(/bin/uname -X|grep '^Machine.*Pentium Pro' >/dev/null) \
 			&& UNAME_MACHINE=i686
-		echo "$UNAME_MACHINE"-pc-sco"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-sco$UNAME_REL
 	else
-		echo "$UNAME_MACHINE"-pc-sysv32
+		GUESS=$UNAME_MACHINE-pc-sysv32
 	fi
-	exit ;;
+	;;
     pc:*:*:*)
 	# Left here for compatibility:
 	# uname -m prints for DJGPP always 'pc', but it prints nothing about
@@ -1127,31 +1238,31 @@
 	# Note: whatever this is, it MUST be the same as what config.sub
 	# prints for the "djgpp" host, or else GDB configure will decide that
 	# this is a cross-build.
-	echo i586-pc-msdosdjgpp
-	exit ;;
+	GUESS=i586-pc-msdosdjgpp
+	;;
     Intel:Mach:3*:*)
-	echo i386-pc-mach3
-	exit ;;
+	GUESS=i386-pc-mach3
+	;;
     paragon:*:*:*)
-	echo i860-intel-osf1
-	exit ;;
+	GUESS=i860-intel-osf1
+	;;
     i860:*:4.*:*) # i860-SVR4
 	if grep Stardent /usr/include/sys/uadmin.h >/dev/null 2>&1 ; then
-	  echo i860-stardent-sysv"$UNAME_RELEASE" # Stardent Vistra i860-SVR4
+	  GUESS=i860-stardent-sysv$UNAME_RELEASE    # Stardent Vistra i860-SVR4
 	else # Add other i860-SVR4 vendors below as they are discovered.
-	  echo i860-unknown-sysv"$UNAME_RELEASE"  # Unknown i860-SVR4
+	  GUESS=i860-unknown-sysv$UNAME_RELEASE     # Unknown i860-SVR4
 	fi
-	exit ;;
+	;;
     mini*:CTIX:SYS*5:*)
 	# "miniframe"
-	echo m68010-convergent-sysv
-	exit ;;
+	GUESS=m68010-convergent-sysv
+	;;
     mc68k:UNIX:SYSTEM5:3.51m)
-	echo m68k-convergent-sysv
-	exit ;;
+	GUESS=m68k-convergent-sysv
+	;;
     M680?0:D-NIX:5.3:*)
-	echo m68k-diab-dnix
-	exit ;;
+	GUESS=m68k-diab-dnix
+	;;
     M68*:*:R3V[5678]*:*)
 	test -r /sysV68 && { echo 'm68k-motorola-sysv'; exit; } ;;
     3[345]??:*:4.0:3.0 | 3[34]??A:*:4.0:3.0 | 3[34]??,*:*:4.0:3.0 | 3[34]??/*:*:4.0:3.0 | 4400:*:4.0:3.0 | 4850:*:4.0:3.0 | SKA40:*:4.0:3.0 | SDS2:*:4.0:3.0 | SHG2:*:4.0:3.0 | S7501*:*:4.0:3.0)
@@ -1176,249 +1287,401 @@
 	/bin/uname -p 2>/dev/null | /bin/grep pteron >/dev/null \
 	    && { echo i586-ncr-sysv4.3"$OS_REL"; exit; } ;;
     m68*:LynxOS:2.*:* | m68*:LynxOS:3.0*:*)
-	echo m68k-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-unknown-lynxos$UNAME_RELEASE
+	;;
     mc68030:UNIX_System_V:4.*:*)
-	echo m68k-atari-sysv4
-	exit ;;
+	GUESS=m68k-atari-sysv4
+	;;
     TSUNAMI:LynxOS:2.*:*)
-	echo sparc-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-unknown-lynxos$UNAME_RELEASE
+	;;
     rs6000:LynxOS:2.*:*)
-	echo rs6000-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=rs6000-unknown-lynxos$UNAME_RELEASE
+	;;
     PowerPC:LynxOS:2.*:* | PowerPC:LynxOS:3.[01]*:* | PowerPC:LynxOS:4.[02]*:*)
-	echo powerpc-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-unknown-lynxos$UNAME_RELEASE
+	;;
     SM[BE]S:UNIX_SV:*:*)
-	echo mips-dde-sysv"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-dde-sysv$UNAME_RELEASE
+	;;
     RM*:ReliantUNIX-*:*:*)
-	echo mips-sni-sysv4
-	exit ;;
+	GUESS=mips-sni-sysv4
+	;;
     RM*:SINIX-*:*:*)
-	echo mips-sni-sysv4
-	exit ;;
+	GUESS=mips-sni-sysv4
+	;;
     *:SINIX-*:*:*)
 	if uname -p 2>/dev/null >/dev/null ; then
 		UNAME_MACHINE=`(uname -p) 2>/dev/null`
-		echo "$UNAME_MACHINE"-sni-sysv4
+		GUESS=$UNAME_MACHINE-sni-sysv4
 	else
-		echo ns32k-sni-sysv
+		GUESS=ns32k-sni-sysv
 	fi
-	exit ;;
+	;;
     PENTIUM:*:4.0*:*)	# Unisys `ClearPath HMP IX 4000' SVR4/MP effort
 			# says <Richard.M.Bartel@ccMail.Census.GOV>
-	echo i586-unisys-sysv4
-	exit ;;
+	GUESS=i586-unisys-sysv4
+	;;
     *:UNIX_System_V:4*:FTX*)
 	# From Gerald Hewes <hewes@openmarket.com>.
 	# How about differentiating between stratus architectures? -djm
-	echo hppa1.1-stratus-sysv4
-	exit ;;
+	GUESS=hppa1.1-stratus-sysv4
+	;;
     *:*:*:FTX*)
 	# From seanf@swdc.stratus.com.
-	echo i860-stratus-sysv4
-	exit ;;
+	GUESS=i860-stratus-sysv4
+	;;
     i*86:VOS:*:*)
 	# From Paul.Green@stratus.com.
-	echo "$UNAME_MACHINE"-stratus-vos
-	exit ;;
+	GUESS=$UNAME_MACHINE-stratus-vos
+	;;
     *:VOS:*:*)
 	# From Paul.Green@stratus.com.
-	echo hppa1.1-stratus-vos
-	exit ;;
+	GUESS=hppa1.1-stratus-vos
+	;;
     mc68*:A/UX:*:*)
-	echo m68k-apple-aux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-apple-aux$UNAME_RELEASE
+	;;
     news*:NEWS-OS:6*:*)
-	echo mips-sony-newsos6
-	exit ;;
+	GUESS=mips-sony-newsos6
+	;;
     R[34]000:*System_V*:*:* | R4000:UNIX_SYSV:*:* | R*000:UNIX_SV:*:*)
-	if [ -d /usr/nec ]; then
-		echo mips-nec-sysv"$UNAME_RELEASE"
+	if test -d /usr/nec; then
+		GUESS=mips-nec-sysv$UNAME_RELEASE
 	else
-		echo mips-unknown-sysv"$UNAME_RELEASE"
+		GUESS=mips-unknown-sysv$UNAME_RELEASE
 	fi
-	exit ;;
+	;;
     BeBox:BeOS:*:*)	# BeOS running on hardware made by Be, PPC only.
-	echo powerpc-be-beos
-	exit ;;
+	GUESS=powerpc-be-beos
+	;;
     BeMac:BeOS:*:*)	# BeOS running on Mac or Mac clone, PPC only.
-	echo powerpc-apple-beos
-	exit ;;
+	GUESS=powerpc-apple-beos
+	;;
     BePC:BeOS:*:*)	# BeOS running on Intel PC compatible.
-	echo i586-pc-beos
-	exit ;;
+	GUESS=i586-pc-beos
+	;;
     BePC:Haiku:*:*)	# Haiku running on Intel PC compatible.
-	echo i586-pc-haiku
-	exit ;;
+	GUESS=i586-pc-haiku
+	;;
     x86_64:Haiku:*:*)
-	echo x86_64-unknown-haiku
-	exit ;;
+	GUESS=x86_64-unknown-haiku
+	;;
     SX-4:SUPER-UX:*:*)
-	echo sx4-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx4-nec-superux$UNAME_RELEASE
+	;;
     SX-5:SUPER-UX:*:*)
-	echo sx5-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx5-nec-superux$UNAME_RELEASE
+	;;
     SX-6:SUPER-UX:*:*)
-	echo sx6-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx6-nec-superux$UNAME_RELEASE
+	;;
     SX-7:SUPER-UX:*:*)
-	echo sx7-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx7-nec-superux$UNAME_RELEASE
+	;;
     SX-8:SUPER-UX:*:*)
-	echo sx8-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx8-nec-superux$UNAME_RELEASE
+	;;
     SX-8R:SUPER-UX:*:*)
-	echo sx8r-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx8r-nec-superux$UNAME_RELEASE
+	;;
     SX-ACE:SUPER-UX:*:*)
-	echo sxace-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sxace-nec-superux$UNAME_RELEASE
+	;;
     Power*:Rhapsody:*:*)
-	echo powerpc-apple-rhapsody"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-apple-rhapsody$UNAME_RELEASE
+	;;
     *:Rhapsody:*:*)
-	echo "$UNAME_MACHINE"-apple-rhapsody"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-apple-rhapsody$UNAME_RELEASE
+	;;
+    arm64:Darwin:*:*)
+	GUESS=aarch64-apple-darwin$UNAME_RELEASE
+	;;
     *:Darwin:*:*)
-	UNAME_PROCESSOR=`uname -p` || UNAME_PROCESSOR=unknown
-	eval "$set_cc_for_build"
-	if test "$UNAME_PROCESSOR" = unknown ; then
-	    UNAME_PROCESSOR=powerpc
+	UNAME_PROCESSOR=`uname -p`
+	case $UNAME_PROCESSOR in
+	    unknown) UNAME_PROCESSOR=powerpc ;;
+	esac
+	if command -v xcode-select > /dev/null 2> /dev/null && \
+		! xcode-select --print-path > /dev/null 2> /dev/null ; then
+	    # Avoid executing cc if there is no toolchain installed as
+	    # cc will be a stub that puts up a graphical alert
+	    # prompting the user to install developer tools.
+	    CC_FOR_BUILD=no_compiler_found
+	else
+	    set_cc_for_build
 	fi
-	if test "`echo "$UNAME_RELEASE" | sed -e 's/\..*//'`" -le 10 ; then
-	    if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
-		if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
-		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
-		       grep IS_64BIT_ARCH >/dev/null
-		then
-		    case $UNAME_PROCESSOR in
-			i386) UNAME_PROCESSOR=x86_64 ;;
-			powerpc) UNAME_PROCESSOR=powerpc64 ;;
-		    esac
-		fi
-		# On 10.4-10.6 one might compile for PowerPC via gcc -arch ppc
-		if (echo '#ifdef __POWERPC__'; echo IS_PPC; echo '#endif') | \
-		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
-		       grep IS_PPC >/dev/null
-		then
-		    UNAME_PROCESSOR=powerpc
-		fi
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
+	    if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
+		   (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		   grep IS_64BIT_ARCH >/dev/null
+	    then
+		case $UNAME_PROCESSOR in
+		    i386) UNAME_PROCESSOR=x86_64 ;;
+		    powerpc) UNAME_PROCESSOR=powerpc64 ;;
+		esac
+	    fi
+	    # On 10.4-10.6 one might compile for PowerPC via gcc -arch ppc
+	    if (echo '#ifdef __POWERPC__'; echo IS_PPC; echo '#endif') | \
+		   (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		   grep IS_PPC >/dev/null
+	    then
+		UNAME_PROCESSOR=powerpc
 	    fi
 	elif test "$UNAME_PROCESSOR" = i386 ; then
-	    # Avoid executing cc on OS X 10.9, as it ships with a stub
-	    # that puts up a graphical alert prompting to install
-	    # developer tools.  Any system running Mac OS X 10.7 or
-	    # later (Darwin 11 and later) is required to have a 64-bit
-	    # processor. This is not true of the ARM version of Darwin
-	    # that Apple uses in portable devices.
-	    UNAME_PROCESSOR=x86_64
+	    # uname -m returns i386 or x86_64
+	    UNAME_PROCESSOR=$UNAME_MACHINE
 	fi
-	echo "$UNAME_PROCESSOR"-apple-darwin"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_PROCESSOR-apple-darwin$UNAME_RELEASE
+	;;
     *:procnto*:*:* | *:QNX:[0123456789]*:*)
 	UNAME_PROCESSOR=`uname -p`
 	if test "$UNAME_PROCESSOR" = x86; then
 		UNAME_PROCESSOR=i386
 		UNAME_MACHINE=pc
 	fi
-	echo "$UNAME_PROCESSOR"-"$UNAME_MACHINE"-nto-qnx"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_PROCESSOR-$UNAME_MACHINE-nto-qnx$UNAME_RELEASE
+	;;
     *:QNX:*:4*)
-	echo i386-pc-qnx
-	exit ;;
+	GUESS=i386-pc-qnx
+	;;
     NEO-*:NONSTOP_KERNEL:*:*)
-	echo neo-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=neo-tandem-nsk$UNAME_RELEASE
+	;;
     NSE-*:NONSTOP_KERNEL:*:*)
-	echo nse-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nse-tandem-nsk$UNAME_RELEASE
+	;;
     NSR-*:NONSTOP_KERNEL:*:*)
-	echo nsr-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsr-tandem-nsk$UNAME_RELEASE
+	;;
     NSV-*:NONSTOP_KERNEL:*:*)
-	echo nsv-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsv-tandem-nsk$UNAME_RELEASE
+	;;
     NSX-*:NONSTOP_KERNEL:*:*)
-	echo nsx-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsx-tandem-nsk$UNAME_RELEASE
+	;;
     *:NonStop-UX:*:*)
-	echo mips-compaq-nonstopux
-	exit ;;
+	GUESS=mips-compaq-nonstopux
+	;;
     BS2000:POSIX*:*:*)
-	echo bs2000-siemens-sysv
-	exit ;;
+	GUESS=bs2000-siemens-sysv
+	;;
     DS/*:UNIX_System_V:*:*)
-	echo "$UNAME_MACHINE"-"$UNAME_SYSTEM"-"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-$UNAME_SYSTEM-$UNAME_RELEASE
+	;;
     *:Plan9:*:*)
 	# "uname -m" is not consistent, so use $cputype instead. 386
 	# is converted to i386 for consistency with other x86
 	# operating systems.
-	if test "$cputype" = 386; then
+	if test "${cputype-}" = 386; then
 	    UNAME_MACHINE=i386
-	else
-	    UNAME_MACHINE="$cputype"
+	elif test "x${cputype-}" != x; then
+	    UNAME_MACHINE=$cputype
 	fi
-	echo "$UNAME_MACHINE"-unknown-plan9
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-plan9
+	;;
     *:TOPS-10:*:*)
-	echo pdp10-unknown-tops10
-	exit ;;
+	GUESS=pdp10-unknown-tops10
+	;;
     *:TENEX:*:*)
-	echo pdp10-unknown-tenex
-	exit ;;
+	GUESS=pdp10-unknown-tenex
+	;;
     KS10:TOPS-20:*:* | KL10:TOPS-20:*:* | TYPE4:TOPS-20:*:*)
-	echo pdp10-dec-tops20
-	exit ;;
+	GUESS=pdp10-dec-tops20
+	;;
     XKL-1:TOPS-20:*:* | TYPE5:TOPS-20:*:*)
-	echo pdp10-xkl-tops20
-	exit ;;
+	GUESS=pdp10-xkl-tops20
+	;;
     *:TOPS-20:*:*)
-	echo pdp10-unknown-tops20
-	exit ;;
+	GUESS=pdp10-unknown-tops20
+	;;
     *:ITS:*:*)
-	echo pdp10-unknown-its
-	exit ;;
+	GUESS=pdp10-unknown-its
+	;;
     SEI:*:*:SEIUX)
-	echo mips-sei-seiux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-sei-seiux$UNAME_RELEASE
+	;;
     *:DragonFly:*:*)
-	echo "$UNAME_MACHINE"-unknown-dragonfly"`echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`"
-	exit ;;
+	DRAGONFLY_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_MACHINE-unknown-dragonfly$DRAGONFLY_REL
+	;;
     *:*VMS:*:*)
 	UNAME_MACHINE=`(uname -p) 2>/dev/null`
-	case "$UNAME_MACHINE" in
-	    A*) echo alpha-dec-vms ; exit ;;
-	    I*) echo ia64-dec-vms ; exit ;;
-	    V*) echo vax-dec-vms ; exit ;;
+	case $UNAME_MACHINE in
+	    A*) GUESS=alpha-dec-vms ;;
+	    I*) GUESS=ia64-dec-vms ;;
+	    V*) GUESS=vax-dec-vms ;;
 	esac ;;
     *:XENIX:*:SysV)
-	echo i386-pc-xenix
-	exit ;;
+	GUESS=i386-pc-xenix
+	;;
     i*86:skyos:*:*)
-	echo "$UNAME_MACHINE"-pc-skyos"`echo "$UNAME_RELEASE" | sed -e 's/ .*$//'`"
-	exit ;;
+	SKYOS_REL=`echo "$UNAME_RELEASE" | sed -e 's/ .*$//'`
+	GUESS=$UNAME_MACHINE-pc-skyos$SKYOS_REL
+	;;
     i*86:rdos:*:*)
-	echo "$UNAME_MACHINE"-pc-rdos
-	exit ;;
-    i*86:AROS:*:*)
-	echo "$UNAME_MACHINE"-pc-aros
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-rdos
+	;;
+    *:AROS:*:*)
+	GUESS=$UNAME_MACHINE-unknown-aros
+	;;
     x86_64:VMkernel:*:*)
-	echo "$UNAME_MACHINE"-unknown-esx
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-esx
+	;;
     amd64:Isilon\ OneFS:*:*)
-	echo x86_64-unknown-onefs
-	exit ;;
+	GUESS=x86_64-unknown-onefs
+	;;
+    *:Unleashed:*:*)
+	GUESS=$UNAME_MACHINE-unknown-unleashed$UNAME_RELEASE
+	;;
 esac
 
+# Do we have a guess based on uname results?
+if test "x$GUESS" != x; then
+    echo "$GUESS"
+    exit
+fi
+
+# No uname command or uname output not recognized.
+set_cc_for_build
+cat > "$dummy.c" <<EOF
+#ifdef _SEQUENT_
+#include <sys/types.h>
+#include <sys/utsname.h>
+#endif
+#if defined(ultrix) || defined(_ultrix) || defined(__ultrix) || defined(__ultrix__)
+#if defined (vax) || defined (__vax) || defined (__vax__) || defined(mips) || defined(__mips) || defined(__mips__) || defined(MIPS) || defined(__MIPS__)
+#include <signal.h>
+#if defined(_SIZE_T_) || defined(SIGLOST)
+#include <sys/utsname.h>
+#endif
+#endif
+#endif
+main ()
+{
+#if defined (sony)
+#if defined (MIPSEB)
+  /* BFD wants "bsd" instead of "newsos".  Perhaps BFD should be changed,
+     I don't know....  */
+  printf ("mips-sony-bsd\n"); exit (0);
+#else
+#include <sys/param.h>
+  printf ("m68k-sony-newsos%s\n",
+#ifdef NEWSOS4
+  "4"
+#else
+  ""
+#endif
+  ); exit (0);
+#endif
+#endif
+
+#if defined (NeXT)
+#if !defined (__ARCHITECTURE__)
+#define __ARCHITECTURE__ "m68k"
+#endif
+  int version;
+  version=`(hostinfo | sed -n 's/.*NeXT Mach \([0-9]*\).*/\1/p') 2>/dev/null`;
+  if (version < 4)
+    printf ("%s-next-nextstep%d\n", __ARCHITECTURE__, version);
+  else
+    printf ("%s-next-openstep%d\n", __ARCHITECTURE__, version);
+  exit (0);
+#endif
+
+#if defined (MULTIMAX) || defined (n16)
+#if defined (UMAXV)
+  printf ("ns32k-encore-sysv\n"); exit (0);
+#else
+#if defined (CMU)
+  printf ("ns32k-encore-mach\n"); exit (0);
+#else
+  printf ("ns32k-encore-bsd\n"); exit (0);
+#endif
+#endif
+#endif
+
+#if defined (__386BSD__)
+  printf ("i386-pc-bsd\n"); exit (0);
+#endif
+
+#if defined (sequent)
+#if defined (i386)
+  printf ("i386-sequent-dynix\n"); exit (0);
+#endif
+#if defined (ns32000)
+  printf ("ns32k-sequent-dynix\n"); exit (0);
+#endif
+#endif
+
+#if defined (_SEQUENT_)
+  struct utsname un;
+
+  uname(&un);
+  if (strncmp(un.version, "V2", 2) == 0) {
+    printf ("i386-sequent-ptx2\n"); exit (0);
+  }
+  if (strncmp(un.version, "V1", 2) == 0) { /* XXX is V1 correct? */
+    printf ("i386-sequent-ptx1\n"); exit (0);
+  }
+  printf ("i386-sequent-ptx\n"); exit (0);
+#endif
+
+#if defined (vax)
+#if !defined (ultrix)
+#include <sys/param.h>
+#if defined (BSD)
+#if BSD == 43
+  printf ("vax-dec-bsd4.3\n"); exit (0);
+#else
+#if BSD == 199006
+  printf ("vax-dec-bsd4.3reno\n"); exit (0);
+#else
+  printf ("vax-dec-bsd\n"); exit (0);
+#endif
+#endif
+#else
+  printf ("vax-dec-bsd\n"); exit (0);
+#endif
+#else
+#if defined(_SIZE_T_) || defined(SIGLOST)
+  struct utsname un;
+  uname (&un);
+  printf ("vax-dec-ultrix%s\n", un.release); exit (0);
+#else
+  printf ("vax-dec-ultrix\n"); exit (0);
+#endif
+#endif
+#endif
+#if defined(ultrix) || defined(_ultrix) || defined(__ultrix) || defined(__ultrix__)
+#if defined(mips) || defined(__mips) || defined(__mips__) || defined(MIPS) || defined(__MIPS__)
+#if defined(_SIZE_T_) || defined(SIGLOST)
+  struct utsname *un;
+  uname (&un);
+  printf ("mips-dec-ultrix%s\n", un.release); exit (0);
+#else
+  printf ("mips-dec-ultrix\n"); exit (0);
+#endif
+#endif
+#endif
+
+#if defined (alliant) && defined (i860)
+  printf ("i860-alliant-bsd\n"); exit (0);
+#endif
+
+  exit (1);
+}
+EOF
+
+$CC_FOR_BUILD -o "$dummy" "$dummy.c" 2>/dev/null && SYSTEM_NAME=`"$dummy"` &&
+	{ echo "$SYSTEM_NAME"; exit; }
+
+# Apollos put the system type in the environment.
+test -d /usr/apollo && { echo "$ISP-apollo-$SYSTYPE"; exit; }
+
 echo "$0: unable to guess system type" >&2
 
-case "$UNAME_MACHINE:$UNAME_SYSTEM" in
+case $UNAME_MACHINE:$UNAME_SYSTEM in
     mips:Linux | mips64:Linux)
 	# If we got here on MIPS GNU/Linux, output extra information.
 	cat >&2 <<EOF
@@ -1435,9 +1698,17 @@
 operating system you are using. If your script is old, overwrite *all*
 copies of config.guess and config.sub with the latest versions from:
 
-  https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess
+  https://git.savannah.gnu.org/cgit/config.git/plain/config.guess
 and
-  https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub
+  https://git.savannah.gnu.org/cgit/config.git/plain/config.sub
+EOF
+
+our_year=`echo $timestamp | sed 's,-.*,,'`
+thisyear=`date +%Y`
+# shellcheck disable=SC2003
+script_age=`expr "$thisyear" - "$our_year"`
+if test "$script_age" -lt 3 ; then
+   cat >&2 <<EOF
 
 If $0 has already been updated, send the following data and any
 information you think might be pertinent to config-patches@gnu.org to
@@ -1465,6 +1736,7 @@
 UNAME_SYSTEM  = "$UNAME_SYSTEM"
 UNAME_VERSION = "$UNAME_VERSION"
 EOF
+fi
 
 exit 1
 
diff --git a/config.h.in b/config.h.in
index 2931048..3309c9f 100644
--- a/config.h.in
+++ b/config.h.in
@@ -15,15 +15,15 @@
 /* Define to 1 if you have the `z' library (-lz). */
 #undef HAVE_LIBZ
 
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
 /* Define to 1 if you have the `pow' function. */
 #undef HAVE_POW
 
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
+/* Define to 1 if you have the <stdio.h> header file. */
+#undef HAVE_STDIO_H
+
 /* Define to 1 if you have the <stdlib.h> header file. */
 #undef HAVE_STDLIB_H
 
@@ -96,7 +96,9 @@
 /* Enable POWERPC VSX optimizations */
 #undef PNG_POWERPC_VSX_OPT
 
-/* Define to 1 if you have the ANSI C header files. */
+/* Define to 1 if all of the C90 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
 #undef STDC_HEADERS
 
 /* Define to 1 if your <sys/time.h> declares `struct tm'. */
@@ -105,22 +107,17 @@
 /* Version number of package */
 #undef VERSION
 
-/* Define to empty if `const' does not conform to ANSI C. */
-#undef const
-
 /* Define to the equivalent of the C99 'restrict' keyword, or to
    nothing if this is not supported.  Do not define if restrict is
-   supported directly.  */
+   supported only directly.  */
 #undef restrict
-/* Work around a bug in Sun C++: it does not support _Restrict or
-   __restrict__, even though the corresponding Sun C compiler ends up with
-   "#define restrict _Restrict" or "#define restrict __restrict__" in the
-   previous line.  Perhaps some future version of Sun C++ will work with
-   restrict; if so, hopefully it defines __RESTRICT like Sun C does.  */
-#if defined __SUNPRO_CC && !defined __RESTRICT
+/* Work around a bug in older versions of Sun C++, which did not
+   #define __restrict__ or support _Restrict or __restrict__
+   even though the corresponding Sun C compiler ended up with
+   "#define restrict _Restrict" or "#define restrict __restrict__"
+   in the previous line.  This workaround can be removed once
+   we assume Oracle Developer Studio 12.5 (2016) or later.  */
+#if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__
 # define _Restrict
 # define __restrict__
 #endif
-
-/* Define to `unsigned int' if <sys/types.h> does not define. */
-#undef size_t
diff --git a/config.sub b/config.sub
index 9ccf09a..d74fb6d 100755
--- a/config.sub
+++ b/config.sub
@@ -1,8 +1,10 @@
 #! /bin/sh
 # Configuration validation subroutine script.
-#   Copyright 1992-2018 Free Software Foundation, Inc.
+#   Copyright 1992-2021 Free Software Foundation, Inc.
 
-timestamp='2018-03-08'
+# shellcheck disable=SC2006,SC2268 # see below for rationale
+
+timestamp='2021-08-14'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -33,7 +35,7 @@
 # Otherwise, we print the canonical config type on stdout and succeed.
 
 # You can get the latest version of this script from:
-# https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub
+# https://git.savannah.gnu.org/cgit/config.git/plain/config.sub
 
 # This file is supposed to be the same for all GNU packages
 # and recognize all the CPU types, system types and aliases
@@ -50,6 +52,13 @@
 #	CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM
 # It is wrong to echo any other type of specification.
 
+# The "shellcheck disable" line above the timestamp inhibits complaints
+# about features and limitations of the classic Bourne shell that were
+# superseded or lifted in POSIX.  However, this script identifies a wide
+# variety of pre-POSIX systems that do not have POSIX shells at all, and
+# even some reasonably current systems (Solaris 10 as case-in-point) still
+# have a pre-POSIX /bin/sh.
+
 me=`echo "$0" | sed -e 's,.*/,,'`
 
 usage="\
@@ -67,7 +76,7 @@
 version="\
 GNU config.sub ($timestamp)
 
-Copyright 1992-2018 Free Software Foundation, Inc.
+Copyright 1992-2021 Free Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@@ -89,7 +98,7 @@
     - )	# Use stdin as input.
        break ;;
     -* )
-       echo "$me: invalid option $1$help"
+       echo "$me: invalid option $1$help" >&2
        exit 1 ;;
 
     *local*)
@@ -110,1223 +119,1181 @@
     exit 1;;
 esac
 
-# Separate what the user gave into CPU-COMPANY and OS or KERNEL-OS (if any).
-# Here we must recognize all the valid KERNEL-OS combinations.
-maybe_os=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`
-case $maybe_os in
-  nto-qnx* | linux-gnu* | linux-android* | linux-dietlibc | linux-newlib* | \
-  linux-musl* | linux-uclibc* | uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | \
-  knetbsd*-gnu* | netbsd*-gnu* | netbsd*-eabi* | \
-  kopensolaris*-gnu* | cloudabi*-eabi* | \
-  storm-chaos* | os2-emx* | rtmk-nova*)
-    os=-$maybe_os
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`
-    ;;
-  android-linux)
-    os=-linux-android
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`-unknown
-    ;;
-  *)
-    basic_machine=`echo "$1" | sed 's/-[^-]*$//'`
-    if [ "$basic_machine" != "$1" ]
-    then os=`echo "$1" | sed 's/.*-/-/'`
-    else os=; fi
-    ;;
-esac
+# Split fields of configuration type
+# shellcheck disable=SC2162
+saved_IFS=$IFS
+IFS="-" read field1 field2 field3 field4 <<EOF
+$1
+EOF
+IFS=$saved_IFS
 
-### Let's recognize common machines as not being operating systems so
-### that things like config.sub decstation-3100 work.  We also
-### recognize some manufacturers as not being operating systems, so we
-### can provide default operating systems below.
-case $os in
-	-sun*os*)
-		# Prevent following clause from handling this invalid input.
+# Separate into logical components for further validation
+case $1 in
+	*-*-*-*-*)
+		echo Invalid configuration \`"$1"\': more than four components >&2
+		exit 1
 		;;
-	-dec* | -mips* | -sequent* | -encore* | -pc532* | -sgi* | -sony* | \
-	-att* | -7300* | -3300* | -delta* | -motorola* | -sun[234]* | \
-	-unicom* | -ibm* | -next | -hp | -isi* | -apollo | -altos* | \
-	-convergent* | -ncr* | -news | -32* | -3600* | -3100* | -hitachi* |\
-	-c[123]* | -convex* | -sun | -crds | -omron* | -dg | -ultra | -tti* | \
-	-harris | -dolphin | -highlevel | -gould | -cbm | -ns | -masscomp | \
-	-apple | -axis | -knuth | -cray | -microblaze*)
-		os=
-		basic_machine=$1
+	*-*-*-*)
+		basic_machine=$field1-$field2
+		basic_os=$field3-$field4
 		;;
-	-bluegene*)
-		os=-cnk
+	*-*-*)
+		# Ambiguous whether COMPANY is present, or skipped and KERNEL-OS is two
+		# parts
+		maybe_os=$field2-$field3
+		case $maybe_os in
+			nto-qnx* | linux-* | uclinux-uclibc* \
+			| uclinux-gnu* | kfreebsd*-gnu* | knetbsd*-gnu* | netbsd*-gnu* \
+			| netbsd*-eabi* | kopensolaris*-gnu* | cloudabi*-eabi* \
+			| storm-chaos* | os2-emx* | rtmk-nova*)
+				basic_machine=$field1
+				basic_os=$maybe_os
+				;;
+			android-linux)
+				basic_machine=$field1-unknown
+				basic_os=linux-android
+				;;
+			*)
+				basic_machine=$field1-$field2
+				basic_os=$field3
+				;;
+		esac
 		;;
-	-sim | -cisco | -oki | -wec | -winbond)
-		os=
-		basic_machine=$1
+	*-*)
+		# A lone config we happen to match not fitting any pattern
+		case $field1-$field2 in
+			decstation-3100)
+				basic_machine=mips-dec
+				basic_os=
+				;;
+			*-*)
+				# Second component is usually, but not always the OS
+				case $field2 in
+					# Prevent following clause from handling this valid os
+					sun*os*)
+						basic_machine=$field1
+						basic_os=$field2
+						;;
+					zephyr*)
+						basic_machine=$field1-unknown
+						basic_os=$field2
+						;;
+					# Manufacturers
+					dec* | mips* | sequent* | encore* | pc533* | sgi* | sony* \
+					| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
+					| unicom* | ibm* | next | hp | isi* | apollo | altos* \
+					| convergent* | ncr* | news | 32* | 3600* | 3100* \
+					| hitachi* | c[123]* | convex* | sun | crds | omron* | dg \
+					| ultra | tti* | harris | dolphin | highlevel | gould \
+					| cbm | ns | masscomp | apple | axis | knuth | cray \
+					| microblaze* | sim | cisco \
+					| oki | wec | wrs | winbond)
+						basic_machine=$field1-$field2
+						basic_os=
+						;;
+					*)
+						basic_machine=$field1
+						basic_os=$field2
+						;;
+				esac
+			;;
+		esac
 		;;
-	-scout)
-		;;
-	-wrs)
-		os=-vxworks
-		basic_machine=$1
-		;;
-	-chorusos*)
-		os=-chorusos
-		basic_machine=$1
-		;;
-	-chorusrdb)
-		os=-chorusrdb
-		basic_machine=$1
-		;;
-	-hiux*)
-		os=-hiuxwe2
-		;;
-	-sco6)
-		os=-sco5v6
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco5)
-		os=-sco3.2v5
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco4)
-		os=-sco3.2v4
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco3.2.[4-9]*)
-		os=`echo $os | sed -e 's/sco3.2./sco3.2v/'`
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco3.2v[4-9]*)
-		# Don't forget version if it is 3.2v4 or newer.
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco5v6*)
-		# Don't forget version if it is 3.2v4 or newer.
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco*)
-		os=-sco3.2v2
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-udk*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-isc)
-		os=-isc2.2
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-clix*)
-		basic_machine=clipper-intergraph
-		;;
-	-isc*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-lynx*178)
-		os=-lynxos178
-		;;
-	-lynx*5)
-		os=-lynxos5
-		;;
-	-lynx*)
-		os=-lynxos
-		;;
-	-ptx*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-sequent/'`
-		;;
-	-psos*)
-		os=-psos
-		;;
-	-mint | -mint[0-9]*)
-		basic_machine=m68k-atari
-		os=-mint
+	*)
+		# Convert single-component short-hands not valid as part of
+		# multi-component configurations.
+		case $field1 in
+			386bsd)
+				basic_machine=i386-pc
+				basic_os=bsd
+				;;
+			a29khif)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			adobe68k)
+				basic_machine=m68010-adobe
+				basic_os=scout
+				;;
+			alliant)
+				basic_machine=fx80-alliant
+				basic_os=
+				;;
+			altos | altos3068)
+				basic_machine=m68k-altos
+				basic_os=
+				;;
+			am29k)
+				basic_machine=a29k-none
+				basic_os=bsd
+				;;
+			amdahl)
+				basic_machine=580-amdahl
+				basic_os=sysv
+				;;
+			amiga)
+				basic_machine=m68k-unknown
+				basic_os=
+				;;
+			amigaos | amigados)
+				basic_machine=m68k-unknown
+				basic_os=amigaos
+				;;
+			amigaunix | amix)
+				basic_machine=m68k-unknown
+				basic_os=sysv4
+				;;
+			apollo68)
+				basic_machine=m68k-apollo
+				basic_os=sysv
+				;;
+			apollo68bsd)
+				basic_machine=m68k-apollo
+				basic_os=bsd
+				;;
+			aros)
+				basic_machine=i386-pc
+				basic_os=aros
+				;;
+			aux)
+				basic_machine=m68k-apple
+				basic_os=aux
+				;;
+			balance)
+				basic_machine=ns32k-sequent
+				basic_os=dynix
+				;;
+			blackfin)
+				basic_machine=bfin-unknown
+				basic_os=linux
+				;;
+			cegcc)
+				basic_machine=arm-unknown
+				basic_os=cegcc
+				;;
+			convex-c1)
+				basic_machine=c1-convex
+				basic_os=bsd
+				;;
+			convex-c2)
+				basic_machine=c2-convex
+				basic_os=bsd
+				;;
+			convex-c32)
+				basic_machine=c32-convex
+				basic_os=bsd
+				;;
+			convex-c34)
+				basic_machine=c34-convex
+				basic_os=bsd
+				;;
+			convex-c38)
+				basic_machine=c38-convex
+				basic_os=bsd
+				;;
+			cray)
+				basic_machine=j90-cray
+				basic_os=unicos
+				;;
+			crds | unos)
+				basic_machine=m68k-crds
+				basic_os=
+				;;
+			da30)
+				basic_machine=m68k-da30
+				basic_os=
+				;;
+			decstation | pmax | pmin | dec3100 | decstatn)
+				basic_machine=mips-dec
+				basic_os=
+				;;
+			delta88)
+				basic_machine=m88k-motorola
+				basic_os=sysv3
+				;;
+			dicos)
+				basic_machine=i686-pc
+				basic_os=dicos
+				;;
+			djgpp)
+				basic_machine=i586-pc
+				basic_os=msdosdjgpp
+				;;
+			ebmon29k)
+				basic_machine=a29k-amd
+				basic_os=ebmon
+				;;
+			es1800 | OSE68k | ose68k | ose | OSE)
+				basic_machine=m68k-ericsson
+				basic_os=ose
+				;;
+			gmicro)
+				basic_machine=tron-gmicro
+				basic_os=sysv
+				;;
+			go32)
+				basic_machine=i386-pc
+				basic_os=go32
+				;;
+			h8300hms)
+				basic_machine=h8300-hitachi
+				basic_os=hms
+				;;
+			h8300xray)
+				basic_machine=h8300-hitachi
+				basic_os=xray
+				;;
+			h8500hms)
+				basic_machine=h8500-hitachi
+				basic_os=hms
+				;;
+			harris)
+				basic_machine=m88k-harris
+				basic_os=sysv3
+				;;
+			hp300 | hp300hpux)
+				basic_machine=m68k-hp
+				basic_os=hpux
+				;;
+			hp300bsd)
+				basic_machine=m68k-hp
+				basic_os=bsd
+				;;
+			hppaosf)
+				basic_machine=hppa1.1-hp
+				basic_os=osf
+				;;
+			hppro)
+				basic_machine=hppa1.1-hp
+				basic_os=proelf
+				;;
+			i386mach)
+				basic_machine=i386-mach
+				basic_os=mach
+				;;
+			isi68 | isi)
+				basic_machine=m68k-isi
+				basic_os=sysv
+				;;
+			m68knommu)
+				basic_machine=m68k-unknown
+				basic_os=linux
+				;;
+			magnum | m3230)
+				basic_machine=mips-mips
+				basic_os=sysv
+				;;
+			merlin)
+				basic_machine=ns32k-utek
+				basic_os=sysv
+				;;
+			mingw64)
+				basic_machine=x86_64-pc
+				basic_os=mingw64
+				;;
+			mingw32)
+				basic_machine=i686-pc
+				basic_os=mingw32
+				;;
+			mingw32ce)
+				basic_machine=arm-unknown
+				basic_os=mingw32ce
+				;;
+			monitor)
+				basic_machine=m68k-rom68k
+				basic_os=coff
+				;;
+			morphos)
+				basic_machine=powerpc-unknown
+				basic_os=morphos
+				;;
+			moxiebox)
+				basic_machine=moxie-unknown
+				basic_os=moxiebox
+				;;
+			msdos)
+				basic_machine=i386-pc
+				basic_os=msdos
+				;;
+			msys)
+				basic_machine=i686-pc
+				basic_os=msys
+				;;
+			mvs)
+				basic_machine=i370-ibm
+				basic_os=mvs
+				;;
+			nacl)
+				basic_machine=le32-unknown
+				basic_os=nacl
+				;;
+			ncr3000)
+				basic_machine=i486-ncr
+				basic_os=sysv4
+				;;
+			netbsd386)
+				basic_machine=i386-pc
+				basic_os=netbsd
+				;;
+			netwinder)
+				basic_machine=armv4l-rebel
+				basic_os=linux
+				;;
+			news | news700 | news800 | news900)
+				basic_machine=m68k-sony
+				basic_os=newsos
+				;;
+			news1000)
+				basic_machine=m68030-sony
+				basic_os=newsos
+				;;
+			necv70)
+				basic_machine=v70-nec
+				basic_os=sysv
+				;;
+			nh3000)
+				basic_machine=m68k-harris
+				basic_os=cxux
+				;;
+			nh[45]000)
+				basic_machine=m88k-harris
+				basic_os=cxux
+				;;
+			nindy960)
+				basic_machine=i960-intel
+				basic_os=nindy
+				;;
+			mon960)
+				basic_machine=i960-intel
+				basic_os=mon960
+				;;
+			nonstopux)
+				basic_machine=mips-compaq
+				basic_os=nonstopux
+				;;
+			os400)
+				basic_machine=powerpc-ibm
+				basic_os=os400
+				;;
+			OSE68000 | ose68000)
+				basic_machine=m68000-ericsson
+				basic_os=ose
+				;;
+			os68k)
+				basic_machine=m68k-none
+				basic_os=os68k
+				;;
+			paragon)
+				basic_machine=i860-intel
+				basic_os=osf
+				;;
+			parisc)
+				basic_machine=hppa-unknown
+				basic_os=linux
+				;;
+			psp)
+				basic_machine=mipsallegrexel-sony
+				basic_os=psp
+				;;
+			pw32)
+				basic_machine=i586-unknown
+				basic_os=pw32
+				;;
+			rdos | rdos64)
+				basic_machine=x86_64-pc
+				basic_os=rdos
+				;;
+			rdos32)
+				basic_machine=i386-pc
+				basic_os=rdos
+				;;
+			rom68k)
+				basic_machine=m68k-rom68k
+				basic_os=coff
+				;;
+			sa29200)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			sei)
+				basic_machine=mips-sei
+				basic_os=seiux
+				;;
+			sequent)
+				basic_machine=i386-sequent
+				basic_os=
+				;;
+			sps7)
+				basic_machine=m68k-bull
+				basic_os=sysv2
+				;;
+			st2000)
+				basic_machine=m68k-tandem
+				basic_os=
+				;;
+			stratus)
+				basic_machine=i860-stratus
+				basic_os=sysv4
+				;;
+			sun2)
+				basic_machine=m68000-sun
+				basic_os=
+				;;
+			sun2os3)
+				basic_machine=m68000-sun
+				basic_os=sunos3
+				;;
+			sun2os4)
+				basic_machine=m68000-sun
+				basic_os=sunos4
+				;;
+			sun3)
+				basic_machine=m68k-sun
+				basic_os=
+				;;
+			sun3os3)
+				basic_machine=m68k-sun
+				basic_os=sunos3
+				;;
+			sun3os4)
+				basic_machine=m68k-sun
+				basic_os=sunos4
+				;;
+			sun4)
+				basic_machine=sparc-sun
+				basic_os=
+				;;
+			sun4os3)
+				basic_machine=sparc-sun
+				basic_os=sunos3
+				;;
+			sun4os4)
+				basic_machine=sparc-sun
+				basic_os=sunos4
+				;;
+			sun4sol2)
+				basic_machine=sparc-sun
+				basic_os=solaris2
+				;;
+			sun386 | sun386i | roadrunner)
+				basic_machine=i386-sun
+				basic_os=
+				;;
+			sv1)
+				basic_machine=sv1-cray
+				basic_os=unicos
+				;;
+			symmetry)
+				basic_machine=i386-sequent
+				basic_os=dynix
+				;;
+			t3e)
+				basic_machine=alphaev5-cray
+				basic_os=unicos
+				;;
+			t90)
+				basic_machine=t90-cray
+				basic_os=unicos
+				;;
+			toad1)
+				basic_machine=pdp10-xkl
+				basic_os=tops20
+				;;
+			tpf)
+				basic_machine=s390x-ibm
+				basic_os=tpf
+				;;
+			udi29k)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			ultra3)
+				basic_machine=a29k-nyu
+				basic_os=sym1
+				;;
+			v810 | necv810)
+				basic_machine=v810-nec
+				basic_os=none
+				;;
+			vaxv)
+				basic_machine=vax-dec
+				basic_os=sysv
+				;;
+			vms)
+				basic_machine=vax-dec
+				basic_os=vms
+				;;
+			vsta)
+				basic_machine=i386-pc
+				basic_os=vsta
+				;;
+			vxworks960)
+				basic_machine=i960-wrs
+				basic_os=vxworks
+				;;
+			vxworks68)
+				basic_machine=m68k-wrs
+				basic_os=vxworks
+				;;
+			vxworks29k)
+				basic_machine=a29k-wrs
+				basic_os=vxworks
+				;;
+			xbox)
+				basic_machine=i686-pc
+				basic_os=mingw32
+				;;
+			ymp)
+				basic_machine=ymp-cray
+				basic_os=unicos
+				;;
+			*)
+				basic_machine=$1
+				basic_os=
+				;;
+		esac
 		;;
 esac
 
-# Decode aliases for certain CPU-COMPANY combinations.
+# Decode 1-component or ad-hoc basic machines
 case $basic_machine in
-	# Recognize the basic CPU types without company name.
-	# Some are omitted here because they have special meanings below.
-	1750a | 580 \
-	| a29k \
-	| aarch64 | aarch64_be \
-	| alpha | alphaev[4-8] | alphaev56 | alphaev6[78] | alphapca5[67] \
-	| alpha64 | alpha64ev[4-8] | alpha64ev56 | alpha64ev6[78] | alpha64pca5[67] \
-	| am33_2.0 \
-	| arc | arceb \
-	| arm | arm[bl]e | arme[lb] | armv[2-8] | armv[3-8][lb] | armv7[arm] \
-	| avr | avr32 \
-	| ba \
-	| be32 | be64 \
-	| bfin \
-	| c4x | c8051 | clipper \
-	| d10v | d30v | dlx | dsp16xx \
-	| e2k | epiphany \
-	| fido | fr30 | frv | ft32 \
-	| h8300 | h8500 | hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
-	| hexagon \
-	| i370 | i860 | i960 | ia16 | ia64 \
-	| ip2k | iq2000 \
-	| k1om \
-	| le32 | le64 \
-	| lm32 \
-	| m32c | m32r | m32rle | m68000 | m68k | m88k \
-	| maxq | mb | microblaze | microblazeel | mcore | mep | metag \
-	| mips | mipsbe | mipseb | mipsel | mipsle \
-	| mips16 \
-	| mips64 | mips64el \
-	| mips64octeon | mips64octeonel \
-	| mips64orion | mips64orionel \
-	| mips64r5900 | mips64r5900el \
-	| mips64vr | mips64vrel \
-	| mips64vr4100 | mips64vr4100el \
-	| mips64vr4300 | mips64vr4300el \
-	| mips64vr5000 | mips64vr5000el \
-	| mips64vr5900 | mips64vr5900el \
-	| mipsisa32 | mipsisa32el \
-	| mipsisa32r2 | mipsisa32r2el \
-	| mipsisa32r6 | mipsisa32r6el \
-	| mipsisa64 | mipsisa64el \
-	| mipsisa64r2 | mipsisa64r2el \
-	| mipsisa64r6 | mipsisa64r6el \
-	| mipsisa64sb1 | mipsisa64sb1el \
-	| mipsisa64sr71k | mipsisa64sr71kel \
-	| mipsr5900 | mipsr5900el \
-	| mipstx39 | mipstx39el \
-	| mn10200 | mn10300 \
-	| moxie \
-	| mt \
-	| msp430 \
-	| nds32 | nds32le | nds32be \
-	| nios | nios2 | nios2eb | nios2el \
-	| ns16k | ns32k \
-	| open8 | or1k | or1knd | or32 \
-	| pdp10 | pj | pjl \
-	| powerpc | powerpc64 | powerpc64le | powerpcle \
-	| pru \
-	| pyramid \
-	| riscv32 | riscv64 \
-	| rl78 | rx \
-	| score \
-	| sh | sh[1234] | sh[24]a | sh[24]aeb | sh[23]e | sh[234]eb | sheb | shbe | shle | sh[1234]le | sh3ele \
-	| sh64 | sh64le \
-	| sparc | sparc64 | sparc64b | sparc64v | sparc86x | sparclet | sparclite \
-	| sparcv8 | sparcv9 | sparcv9b | sparcv9v \
-	| spu \
-	| tahoe | tic4x | tic54x | tic55x | tic6x | tic80 | tron \
-	| ubicom32 \
-	| v850 | v850e | v850e1 | v850e2 | v850es | v850e2v3 \
-	| visium \
-	| wasm32 \
-	| x86 | xc16x | xstormy16 | xtensa \
-	| z8k | z80)
-		basic_machine=$basic_machine-unknown
+	# Here we handle the default manufacturer of certain CPU types.  It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	w89k)
+		cpu=hppa1.1
+		vendor=winbond
 		;;
-	c54x)
-		basic_machine=tic54x-unknown
+	op50n)
+		cpu=hppa1.1
+		vendor=oki
 		;;
-	c55x)
-		basic_machine=tic55x-unknown
+	op60c)
+		cpu=hppa1.1
+		vendor=oki
 		;;
-	c6x)
-		basic_machine=tic6x-unknown
+	ibm*)
+		cpu=i370
+		vendor=ibm
+		;;
+	orion105)
+		cpu=clipper
+		vendor=highlevel
+		;;
+	mac | mpw | mac-mpw)
+		cpu=m68k
+		vendor=apple
+		;;
+	pmac | pmac-mpw)
+		cpu=powerpc
+		vendor=apple
+		;;
+
+	# Recognize the various machine names and aliases which stand
+	# for a CPU type and a company and sometimes even an OS.
+	3b1 | 7300 | 7300-att | att-7300 | pc7300 | safari | unixpc)
+		cpu=m68000
+		vendor=att
+		;;
+	3b*)
+		cpu=we32k
+		vendor=att
+		;;
+	bluegene*)
+		cpu=powerpc
+		vendor=ibm
+		basic_os=cnk
+		;;
+	decsystem10* | dec10*)
+		cpu=pdp10
+		vendor=dec
+		basic_os=tops10
+		;;
+	decsystem20* | dec20*)
+		cpu=pdp10
+		vendor=dec
+		basic_os=tops20
+		;;
+	delta | 3300 | motorola-3300 | motorola-delta \
+	      | 3300-motorola | delta-motorola)
+		cpu=m68k
+		vendor=motorola
+		;;
+	dpx2*)
+		cpu=m68k
+		vendor=bull
+		basic_os=sysv3
+		;;
+	encore | umax | mmax)
+		cpu=ns32k
+		vendor=encore
+		;;
+	elxsi)
+		cpu=elxsi
+		vendor=elxsi
+		basic_os=${basic_os:-bsd}
+		;;
+	fx2800)
+		cpu=i860
+		vendor=alliant
+		;;
+	genix)
+		cpu=ns32k
+		vendor=ns
+		;;
+	h3050r* | hiux*)
+		cpu=hppa1.1
+		vendor=hitachi
+		basic_os=hiuxwe2
+		;;
+	hp3k9[0-9][0-9] | hp9[0-9][0-9])
+		cpu=hppa1.0
+		vendor=hp
+		;;
+	hp9k2[0-9][0-9] | hp9k31[0-9])
+		cpu=m68000
+		vendor=hp
+		;;
+	hp9k3[2-9][0-9])
+		cpu=m68k
+		vendor=hp
+		;;
+	hp9k6[0-9][0-9] | hp6[0-9][0-9])
+		cpu=hppa1.0
+		vendor=hp
+		;;
+	hp9k7[0-79][0-9] | hp7[0-79][0-9])
+		cpu=hppa1.1
+		vendor=hp
+		;;
+	hp9k78[0-9] | hp78[0-9])
+		# FIXME: really hppa2.0-hp
+		cpu=hppa1.1
+		vendor=hp
+		;;
+	hp9k8[67]1 | hp8[67]1 | hp9k80[24] | hp80[24] | hp9k8[78]9 | hp8[78]9 | hp9k893 | hp893)
+		# FIXME: really hppa2.0-hp
+		cpu=hppa1.1
+		vendor=hp
+		;;
+	hp9k8[0-9][13679] | hp8[0-9][13679])
+		cpu=hppa1.1
+		vendor=hp
+		;;
+	hp9k8[0-9][0-9] | hp8[0-9][0-9])
+		cpu=hppa1.0
+		vendor=hp
+		;;
+	i*86v32)
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv32
+		;;
+	i*86v4*)
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv4
+		;;
+	i*86v)
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv
+		;;
+	i*86sol2)
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=solaris2
+		;;
+	j90 | j90-cray)
+		cpu=j90
+		vendor=cray
+		basic_os=${basic_os:-unicos}
+		;;
+	iris | iris4d)
+		cpu=mips
+		vendor=sgi
+		case $basic_os in
+		    irix*)
+			;;
+		    *)
+			basic_os=irix4
+			;;
+		esac
+		;;
+	miniframe)
+		cpu=m68000
+		vendor=convergent
+		;;
+	*mint | mint[0-9]* | *MiNT | *MiNT[0-9]*)
+		cpu=m68k
+		vendor=atari
+		basic_os=mint
+		;;
+	news-3600 | risc-news)
+		cpu=mips
+		vendor=sony
+		basic_os=newsos
+		;;
+	next | m*-next)
+		cpu=m68k
+		vendor=next
+		case $basic_os in
+		    openstep*)
+		        ;;
+		    nextstep*)
+			;;
+		    ns2*)
+		      basic_os=nextstep2
+			;;
+		    *)
+		      basic_os=nextstep3
+			;;
+		esac
+		;;
+	np1)
+		cpu=np1
+		vendor=gould
+		;;
+	op50n-* | op60c-*)
+		cpu=hppa1.1
+		vendor=oki
+		basic_os=proelf
+		;;
+	pa-hitachi)
+		cpu=hppa1.1
+		vendor=hitachi
+		basic_os=hiuxwe2
+		;;
+	pbd)
+		cpu=sparc
+		vendor=tti
+		;;
+	pbb)
+		cpu=m68k
+		vendor=tti
+		;;
+	pc532)
+		cpu=ns32k
+		vendor=pc532
+		;;
+	pn)
+		cpu=pn
+		vendor=gould
+		;;
+	power)
+		cpu=power
+		vendor=ibm
+		;;
+	ps2)
+		cpu=i386
+		vendor=ibm
+		;;
+	rm[46]00)
+		cpu=mips
+		vendor=siemens
+		;;
+	rtpc | rtpc-*)
+		cpu=romp
+		vendor=ibm
+		;;
+	sde)
+		cpu=mipsisa32
+		vendor=sde
+		basic_os=${basic_os:-elf}
+		;;
+	simso-wrs)
+		cpu=sparclite
+		vendor=wrs
+		basic_os=vxworks
+		;;
+	tower | tower-32)
+		cpu=m68k
+		vendor=ncr
+		;;
+	vpp*|vx|vx-*)
+		cpu=f301
+		vendor=fujitsu
+		;;
+	w65)
+		cpu=w65
+		vendor=wdc
+		;;
+	w89k-*)
+		cpu=hppa1.1
+		vendor=winbond
+		basic_os=proelf
+		;;
+	none)
+		cpu=none
+		vendor=none
 		;;
 	leon|leon[3-9])
-		basic_machine=sparc-$basic_machine
+		cpu=sparc
+		vendor=$basic_machine
 		;;
-	m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip)
-		basic_machine=$basic_machine-unknown
-		os=-none
-		;;
-	m88110 | m680[12346]0 | m683?2 | m68360 | m5200 | v70 | w65)
-		;;
-	ms1)
-		basic_machine=mt-unknown
+	leon-*|leon[3-9]-*)
+		cpu=sparc
+		vendor=`echo "$basic_machine" | sed 's/-.*//'`
 		;;
 
-	strongarm | thumb | xscale)
-		basic_machine=arm-unknown
+	*-*)
+		# shellcheck disable=SC2162
+		saved_IFS=$IFS
+		IFS="-" read cpu vendor <<EOF
+$basic_machine
+EOF
+		IFS=$saved_IFS
 		;;
-	xgate)
-		basic_machine=$basic_machine-unknown
-		os=-none
-		;;
-	xscaleeb)
-		basic_machine=armeb-unknown
-		;;
-
-	xscaleel)
-		basic_machine=armel-unknown
-		;;
-
 	# We use `pc' rather than `unknown'
 	# because (1) that's what they normally are, and
 	# (2) the word "unknown" tends to confuse beginning users.
 	i*86 | x86_64)
-	  basic_machine=$basic_machine-pc
-	  ;;
-	# Object if more than one company name word.
-	*-*-*)
-		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
-		exit 1
+		cpu=$basic_machine
+		vendor=pc
 		;;
-	# Recognize the basic CPU types with company name.
-	580-* \
-	| a29k-* \
-	| aarch64-* | aarch64_be-* \
-	| alpha-* | alphaev[4-8]-* | alphaev56-* | alphaev6[78]-* \
-	| alpha64-* | alpha64ev[4-8]-* | alpha64ev56-* | alpha64ev6[78]-* \
-	| alphapca5[67]-* | alpha64pca5[67]-* | arc-* | arceb-* \
-	| arm-*  | armbe-* | armle-* | armeb-* | armv*-* \
-	| avr-* | avr32-* \
-	| ba-* \
-	| be32-* | be64-* \
-	| bfin-* | bs2000-* \
-	| c[123]* | c30-* | [cjt]90-* | c4x-* \
-	| c8051-* | clipper-* | craynv-* | cydra-* \
-	| d10v-* | d30v-* | dlx-* \
-	| e2k-* | elxsi-* \
-	| f30[01]-* | f700-* | fido-* | fr30-* | frv-* | fx80-* \
-	| h8300-* | h8500-* \
-	| hppa-* | hppa1.[01]-* | hppa2.0-* | hppa2.0[nw]-* | hppa64-* \
-	| hexagon-* \
-	| i*86-* | i860-* | i960-* | ia16-* | ia64-* \
-	| ip2k-* | iq2000-* \
-	| k1om-* \
-	| le32-* | le64-* \
-	| lm32-* \
-	| m32c-* | m32r-* | m32rle-* \
-	| m68000-* | m680[012346]0-* | m68360-* | m683?2-* | m68k-* \
-	| m88110-* | m88k-* | maxq-* | mcore-* | metag-* \
-	| microblaze-* | microblazeel-* \
-	| mips-* | mipsbe-* | mipseb-* | mipsel-* | mipsle-* \
-	| mips16-* \
-	| mips64-* | mips64el-* \
-	| mips64octeon-* | mips64octeonel-* \
-	| mips64orion-* | mips64orionel-* \
-	| mips64r5900-* | mips64r5900el-* \
-	| mips64vr-* | mips64vrel-* \
-	| mips64vr4100-* | mips64vr4100el-* \
-	| mips64vr4300-* | mips64vr4300el-* \
-	| mips64vr5000-* | mips64vr5000el-* \
-	| mips64vr5900-* | mips64vr5900el-* \
-	| mipsisa32-* | mipsisa32el-* \
-	| mipsisa32r2-* | mipsisa32r2el-* \
-	| mipsisa32r6-* | mipsisa32r6el-* \
-	| mipsisa64-* | mipsisa64el-* \
-	| mipsisa64r2-* | mipsisa64r2el-* \
-	| mipsisa64r6-* | mipsisa64r6el-* \
-	| mipsisa64sb1-* | mipsisa64sb1el-* \
-	| mipsisa64sr71k-* | mipsisa64sr71kel-* \
-	| mipsr5900-* | mipsr5900el-* \
-	| mipstx39-* | mipstx39el-* \
-	| mmix-* \
-	| mt-* \
-	| msp430-* \
-	| nds32-* | nds32le-* | nds32be-* \
-	| nios-* | nios2-* | nios2eb-* | nios2el-* \
-	| none-* | np1-* | ns16k-* | ns32k-* \
-	| open8-* \
-	| or1k*-* \
-	| orion-* \
-	| pdp10-* | pdp11-* | pj-* | pjl-* | pn-* | power-* \
-	| powerpc-* | powerpc64-* | powerpc64le-* | powerpcle-* \
-	| pru-* \
-	| pyramid-* \
-	| riscv32-* | riscv64-* \
-	| rl78-* | romp-* | rs6000-* | rx-* \
-	| sh-* | sh[1234]-* | sh[24]a-* | sh[24]aeb-* | sh[23]e-* | sh[34]eb-* | sheb-* | shbe-* \
-	| shle-* | sh[1234]le-* | sh3ele-* | sh64-* | sh64le-* \
-	| sparc-* | sparc64-* | sparc64b-* | sparc64v-* | sparc86x-* | sparclet-* \
-	| sparclite-* \
-	| sparcv8-* | sparcv9-* | sparcv9b-* | sparcv9v-* | sv1-* | sx*-* \
-	| tahoe-* \
-	| tic30-* | tic4x-* | tic54x-* | tic55x-* | tic6x-* | tic80-* \
-	| tile*-* \
-	| tron-* \
-	| ubicom32-* \
-	| v850-* | v850e-* | v850e1-* | v850es-* | v850e2-* | v850e2v3-* \
-	| vax-* \
-	| visium-* \
-	| wasm32-* \
-	| we32k-* \
-	| x86-* | x86_64-* | xc16x-* | xps100-* \
-	| xstormy16-* | xtensa*-* \
-	| ymp-* \
-	| z8k-* | z80-*)
-		;;
-	# Recognize the basic CPU types without company name, with glob match.
-	xtensa*)
-		basic_machine=$basic_machine-unknown
-		;;
-	# Recognize the various machine names and aliases which stand
-	# for a CPU type and a company and sometimes even an OS.
-	386bsd)
-		basic_machine=i386-pc
-		os=-bsd
-		;;
-	3b1 | 7300 | 7300-att | att-7300 | pc7300 | safari | unixpc)
-		basic_machine=m68000-att
-		;;
-	3b*)
-		basic_machine=we32k-att
-		;;
-	a29khif)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	abacus)
-		basic_machine=abacus-unknown
-		;;
-	adobe68k)
-		basic_machine=m68010-adobe
-		os=-scout
-		;;
-	alliant | fx80)
-		basic_machine=fx80-alliant
-		;;
-	altos | altos3068)
-		basic_machine=m68k-altos
-		;;
-	am29k)
-		basic_machine=a29k-none
-		os=-bsd
-		;;
-	amd64)
-		basic_machine=x86_64-pc
-		;;
-	amd64-*)
-		basic_machine=x86_64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	amdahl)
-		basic_machine=580-amdahl
-		os=-sysv
-		;;
-	amiga | amiga-*)
-		basic_machine=m68k-unknown
-		;;
-	amigaos | amigados)
-		basic_machine=m68k-unknown
-		os=-amigaos
-		;;
-	amigaunix | amix)
-		basic_machine=m68k-unknown
-		os=-sysv4
-		;;
-	apollo68)
-		basic_machine=m68k-apollo
-		os=-sysv
-		;;
-	apollo68bsd)
-		basic_machine=m68k-apollo
-		os=-bsd
-		;;
-	aros)
-		basic_machine=i386-pc
-		os=-aros
-		;;
-	asmjs)
-		basic_machine=asmjs-unknown
-		;;
-	aux)
-		basic_machine=m68k-apple
-		os=-aux
-		;;
-	balance)
-		basic_machine=ns32k-sequent
-		os=-dynix
-		;;
-	blackfin)
-		basic_machine=bfin-unknown
-		os=-linux
-		;;
-	blackfin-*)
-		basic_machine=bfin-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
-		;;
-	bluegene*)
-		basic_machine=powerpc-ibm
-		os=-cnk
-		;;
-	c54x-*)
-		basic_machine=tic54x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c55x-*)
-		basic_machine=tic55x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c6x-*)
-		basic_machine=tic6x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c90)
-		basic_machine=c90-cray
-		os=-unicos
-		;;
-	cegcc)
-		basic_machine=arm-unknown
-		os=-cegcc
-		;;
-	convex-c1)
-		basic_machine=c1-convex
-		os=-bsd
-		;;
-	convex-c2)
-		basic_machine=c2-convex
-		os=-bsd
-		;;
-	convex-c32)
-		basic_machine=c32-convex
-		os=-bsd
-		;;
-	convex-c34)
-		basic_machine=c34-convex
-		os=-bsd
-		;;
-	convex-c38)
-		basic_machine=c38-convex
-		os=-bsd
-		;;
-	cray | j90)
-		basic_machine=j90-cray
-		os=-unicos
-		;;
-	craynv)
-		basic_machine=craynv-cray
-		os=-unicosmp
-		;;
-	cr16 | cr16-*)
-		basic_machine=cr16-unknown
-		os=-elf
-		;;
-	crds | unos)
-		basic_machine=m68k-crds
-		;;
-	crisv32 | crisv32-* | etraxfs*)
-		basic_machine=crisv32-axis
-		;;
-	cris | cris-* | etrax*)
-		basic_machine=cris-axis
-		;;
-	crx)
-		basic_machine=crx-unknown
-		os=-elf
-		;;
-	da30 | da30-*)
-		basic_machine=m68k-da30
-		;;
-	decstation | decstation-3100 | pmax | pmax-* | pmin | dec3100 | decstatn)
-		basic_machine=mips-dec
-		;;
-	decsystem10* | dec10*)
-		basic_machine=pdp10-dec
-		os=-tops10
-		;;
-	decsystem20* | dec20*)
-		basic_machine=pdp10-dec
-		os=-tops20
-		;;
-	delta | 3300 | motorola-3300 | motorola-delta \
-	      | 3300-motorola | delta-motorola)
-		basic_machine=m68k-motorola
-		;;
-	delta88)
-		basic_machine=m88k-motorola
-		os=-sysv3
-		;;
-	dicos)
-		basic_machine=i686-pc
-		os=-dicos
-		;;
-	djgpp)
-		basic_machine=i586-pc
-		os=-msdosdjgpp
-		;;
-	dpx20 | dpx20-*)
-		basic_machine=rs6000-bull
-		os=-bosx
-		;;
-	dpx2*)
-		basic_machine=m68k-bull
-		os=-sysv3
-		;;
-	e500v[12])
-		basic_machine=powerpc-unknown
-		os=$os"spe"
-		;;
-	e500v[12]-*)
-		basic_machine=powerpc-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=$os"spe"
-		;;
-	ebmon29k)
-		basic_machine=a29k-amd
-		os=-ebmon
-		;;
-	elxsi)
-		basic_machine=elxsi-elxsi
-		os=-bsd
-		;;
-	encore | umax | mmax)
-		basic_machine=ns32k-encore
-		;;
-	es1800 | OSE68k | ose68k | ose | OSE)
-		basic_machine=m68k-ericsson
-		os=-ose
-		;;
-	fx2800)
-		basic_machine=i860-alliant
-		;;
-	genix)
-		basic_machine=ns32k-ns
-		;;
-	gmicro)
-		basic_machine=tron-gmicro
-		os=-sysv
-		;;
-	go32)
-		basic_machine=i386-pc
-		os=-go32
-		;;
-	h3050r* | hiux*)
-		basic_machine=hppa1.1-hitachi
-		os=-hiuxwe2
-		;;
-	h8300hms)
-		basic_machine=h8300-hitachi
-		os=-hms
-		;;
-	h8300xray)
-		basic_machine=h8300-hitachi
-		os=-xray
-		;;
-	h8500hms)
-		basic_machine=h8500-hitachi
-		os=-hms
-		;;
-	harris)
-		basic_machine=m88k-harris
-		os=-sysv3
-		;;
-	hp300-*)
-		basic_machine=m68k-hp
-		;;
-	hp300bsd)
-		basic_machine=m68k-hp
-		os=-bsd
-		;;
-	hp300hpux)
-		basic_machine=m68k-hp
-		os=-hpux
-		;;
-	hp3k9[0-9][0-9] | hp9[0-9][0-9])
-		basic_machine=hppa1.0-hp
-		;;
-	hp9k2[0-9][0-9] | hp9k31[0-9])
-		basic_machine=m68000-hp
-		;;
-	hp9k3[2-9][0-9])
-		basic_machine=m68k-hp
-		;;
-	hp9k6[0-9][0-9] | hp6[0-9][0-9])
-		basic_machine=hppa1.0-hp
-		;;
-	hp9k7[0-79][0-9] | hp7[0-79][0-9])
-		basic_machine=hppa1.1-hp
-		;;
-	hp9k78[0-9] | hp78[0-9])
-		# FIXME: really hppa2.0-hp
-		basic_machine=hppa1.1-hp
-		;;
-	hp9k8[67]1 | hp8[67]1 | hp9k80[24] | hp80[24] | hp9k8[78]9 | hp8[78]9 | hp9k893 | hp893)
-		# FIXME: really hppa2.0-hp
-		basic_machine=hppa1.1-hp
-		;;
-	hp9k8[0-9][13679] | hp8[0-9][13679])
-		basic_machine=hppa1.1-hp
-		;;
-	hp9k8[0-9][0-9] | hp8[0-9][0-9])
-		basic_machine=hppa1.0-hp
-		;;
-	hppaosf)
-		basic_machine=hppa1.1-hp
-		os=-osf
-		;;
-	hppro)
-		basic_machine=hppa1.1-hp
-		os=-proelf
-		;;
-	i370-ibm* | ibm*)
-		basic_machine=i370-ibm
-		;;
-	i*86v32)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv32
-		;;
-	i*86v4*)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv4
-		;;
-	i*86v)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv
-		;;
-	i*86sol2)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-solaris2
-		;;
-	i386mach)
-		basic_machine=i386-mach
-		os=-mach
-		;;
-	vsta)
-		basic_machine=i386-unknown
-		os=-vsta
-		;;
-	iris | iris4d)
-		basic_machine=mips-sgi
-		case $os in
-		    -irix*)
-			;;
-		    *)
-			os=-irix4
-			;;
-		esac
-		;;
-	isi68 | isi)
-		basic_machine=m68k-isi
-		os=-sysv
-		;;
-	leon-*|leon[3-9]-*)
-		basic_machine=sparc-`echo "$basic_machine" | sed 's/-.*//'`
-		;;
-	m68knommu)
-		basic_machine=m68k-unknown
-		os=-linux
-		;;
-	m68knommu-*)
-		basic_machine=m68k-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
-		;;
-	magnum | m3230)
-		basic_machine=mips-mips
-		os=-sysv
-		;;
-	merlin)
-		basic_machine=ns32k-utek
-		os=-sysv
-		;;
-	microblaze*)
-		basic_machine=microblaze-xilinx
-		;;
-	mingw64)
-		basic_machine=x86_64-pc
-		os=-mingw64
-		;;
-	mingw32)
-		basic_machine=i686-pc
-		os=-mingw32
-		;;
-	mingw32ce)
-		basic_machine=arm-unknown
-		os=-mingw32ce
-		;;
-	miniframe)
-		basic_machine=m68000-convergent
-		;;
-	*mint | -mint[0-9]* | *MiNT | *MiNT[0-9]*)
-		basic_machine=m68k-atari
-		os=-mint
-		;;
-	mips3*-*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/mips3/mips64/'`
-		;;
-	mips3*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/mips3/mips64/'`-unknown
-		;;
-	monitor)
-		basic_machine=m68k-rom68k
-		os=-coff
-		;;
-	morphos)
-		basic_machine=powerpc-unknown
-		os=-morphos
-		;;
-	moxiebox)
-		basic_machine=moxie-unknown
-		os=-moxiebox
-		;;
-	msdos)
-		basic_machine=i386-pc
-		os=-msdos
-		;;
-	ms1-*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/ms1-/mt-/'`
-		;;
-	msys)
-		basic_machine=i686-pc
-		os=-msys
-		;;
-	mvs)
-		basic_machine=i370-ibm
-		os=-mvs
-		;;
-	nacl)
-		basic_machine=le32-unknown
-		os=-nacl
-		;;
-	ncr3000)
-		basic_machine=i486-ncr
-		os=-sysv4
-		;;
-	netbsd386)
-		basic_machine=i386-unknown
-		os=-netbsd
-		;;
-	netwinder)
-		basic_machine=armv4l-rebel
-		os=-linux
-		;;
-	news | news700 | news800 | news900)
-		basic_machine=m68k-sony
-		os=-newsos
-		;;
-	news1000)
-		basic_machine=m68030-sony
-		os=-newsos
-		;;
-	news-3600 | risc-news)
-		basic_machine=mips-sony
-		os=-newsos
-		;;
-	necv70)
-		basic_machine=v70-nec
-		os=-sysv
-		;;
-	next | m*-next)
-		basic_machine=m68k-next
-		case $os in
-		    -nextstep* )
-			;;
-		    -ns2*)
-		      os=-nextstep2
-			;;
-		    *)
-		      os=-nextstep3
-			;;
-		esac
-		;;
-	nh3000)
-		basic_machine=m68k-harris
-		os=-cxux
-		;;
-	nh[45]000)
-		basic_machine=m88k-harris
-		os=-cxux
-		;;
-	nindy960)
-		basic_machine=i960-intel
-		os=-nindy
-		;;
-	mon960)
-		basic_machine=i960-intel
-		os=-mon960
-		;;
-	nonstopux)
-		basic_machine=mips-compaq
-		os=-nonstopux
-		;;
-	np1)
-		basic_machine=np1-gould
-		;;
-	neo-tandem)
-		basic_machine=neo-tandem
-		;;
-	nse-tandem)
-		basic_machine=nse-tandem
-		;;
-	nsr-tandem)
-		basic_machine=nsr-tandem
-		;;
-	nsv-tandem)
-		basic_machine=nsv-tandem
-		;;
-	nsx-tandem)
-		basic_machine=nsx-tandem
-		;;
-	op50n-* | op60c-*)
-		basic_machine=hppa1.1-oki
-		os=-proelf
-		;;
-	openrisc | openrisc-*)
-		basic_machine=or32-unknown
-		;;
-	os400)
-		basic_machine=powerpc-ibm
-		os=-os400
-		;;
-	OSE68000 | ose68000)
-		basic_machine=m68000-ericsson
-		os=-ose
-		;;
-	os68k)
-		basic_machine=m68k-none
-		os=-os68k
-		;;
-	pa-hitachi)
-		basic_machine=hppa1.1-hitachi
-		os=-hiuxwe2
-		;;
-	paragon)
-		basic_machine=i860-intel
-		os=-osf
-		;;
-	parisc)
-		basic_machine=hppa-unknown
-		os=-linux
-		;;
-	parisc-*)
-		basic_machine=hppa-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
-		;;
-	pbd)
-		basic_machine=sparc-tti
-		;;
-	pbb)
-		basic_machine=m68k-tti
-		;;
-	pc532 | pc532-*)
-		basic_machine=ns32k-pc532
-		;;
+	# These rules are duplicated from below for sake of the special case above;
+	# i.e. things that normalized to x86 arches should also default to "pc"
 	pc98)
-		basic_machine=i386-pc
+		cpu=i386
+		vendor=pc
 		;;
-	pc98-*)
-		basic_machine=i386-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	x64 | amd64)
+		cpu=x86_64
+		vendor=pc
 		;;
-	pentium | p5 | k5 | k6 | nexgen | viac3)
-		basic_machine=i586-pc
+	# Recognize the basic CPU types without company name.
+	*)
+		cpu=$basic_machine
+		vendor=unknown
 		;;
-	pentiumpro | p6 | 6x86 | athlon | athlon_*)
-		basic_machine=i686-pc
+esac
+
+unset -v basic_machine
+
+# Decode basic machines in the full and proper CPU-Company form.
+case $cpu-$vendor in
+	# Here we handle the default manufacturer of certain CPU types in canonical form. It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	craynv-unknown)
+		vendor=cray
+		basic_os=${basic_os:-unicosmp}
 		;;
-	pentiumii | pentium2 | pentiumiii | pentium3)
-		basic_machine=i686-pc
+	c90-unknown | c90-cray)
+		vendor=cray
+		basic_os=${Basic_os:-unicos}
 		;;
-	pentium4)
-		basic_machine=i786-pc
+	fx80-unknown)
+		vendor=alliant
 		;;
-	pentium-* | p5-* | k5-* | k6-* | nexgen-* | viac3-*)
-		basic_machine=i586-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	romp-unknown)
+		vendor=ibm
 		;;
-	pentiumpro-* | p6-* | 6x86-* | athlon-*)
-		basic_machine=i686-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	mmix-unknown)
+		vendor=knuth
 		;;
-	pentiumii-* | pentium2-* | pentiumiii-* | pentium3-*)
-		basic_machine=i686-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	microblaze-unknown | microblazeel-unknown)
+		vendor=xilinx
 		;;
-	pentium4-*)
-		basic_machine=i786-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	rs6000-unknown)
+		vendor=ibm
 		;;
-	pn)
-		basic_machine=pn-gould
+	vax-unknown)
+		vendor=dec
 		;;
-	power)	basic_machine=power-ibm
+	pdp11-unknown)
+		vendor=dec
 		;;
-	ppc | ppcbe)	basic_machine=powerpc-unknown
+	we32k-unknown)
+		vendor=att
 		;;
-	ppc-* | ppcbe-*)
-		basic_machine=powerpc-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	cydra-unknown)
+		vendor=cydrome
 		;;
-	ppcle | powerpclittle)
-		basic_machine=powerpcle-unknown
+	i370-ibm*)
+		vendor=ibm
 		;;
-	ppcle-* | powerpclittle-*)
-		basic_machine=powerpcle-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	orion-unknown)
+		vendor=highlevel
 		;;
-	ppc64)	basic_machine=powerpc64-unknown
-		;;
-	ppc64-*) basic_machine=powerpc64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	ppc64le | powerpc64little)
-		basic_machine=powerpc64le-unknown
-		;;
-	ppc64le-* | powerpc64little-*)
-		basic_machine=powerpc64le-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	ps2)
-		basic_machine=i386-ibm
-		;;
-	pw32)
-		basic_machine=i586-unknown
-		os=-pw32
-		;;
-	rdos | rdos64)
-		basic_machine=x86_64-pc
-		os=-rdos
-		;;
-	rdos32)
-		basic_machine=i386-pc
-		os=-rdos
-		;;
-	rom68k)
-		basic_machine=m68k-rom68k
-		os=-coff
-		;;
-	rm[46]00)
-		basic_machine=mips-siemens
-		;;
-	rtpc | rtpc-*)
-		basic_machine=romp-ibm
-		;;
-	s390 | s390-*)
-		basic_machine=s390-ibm
-		;;
-	s390x | s390x-*)
-		basic_machine=s390x-ibm
-		;;
-	sa29200)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	sb1)
-		basic_machine=mipsisa64sb1-unknown
-		;;
-	sb1el)
-		basic_machine=mipsisa64sb1el-unknown
-		;;
-	sde)
-		basic_machine=mipsisa32-sde
-		os=-elf
-		;;
-	sei)
-		basic_machine=mips-sei
-		os=-seiux
-		;;
-	sequent)
-		basic_machine=i386-sequent
-		;;
-	sh5el)
-		basic_machine=sh5le-unknown
-		;;
-	simso-wrs)
-		basic_machine=sparclite-wrs
-		os=-vxworks
-		;;
-	sps7)
-		basic_machine=m68k-bull
-		os=-sysv2
-		;;
-	spur)
-		basic_machine=spur-unknown
-		;;
-	st2000)
-		basic_machine=m68k-tandem
-		;;
-	stratus)
-		basic_machine=i860-stratus
-		os=-sysv4
-		;;
-	strongarm-* | thumb-*)
-		basic_machine=arm-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	sun2)
-		basic_machine=m68000-sun
-		;;
-	sun2os3)
-		basic_machine=m68000-sun
-		os=-sunos3
-		;;
-	sun2os4)
-		basic_machine=m68000-sun
-		os=-sunos4
-		;;
-	sun3os3)
-		basic_machine=m68k-sun
-		os=-sunos3
-		;;
-	sun3os4)
-		basic_machine=m68k-sun
-		os=-sunos4
-		;;
-	sun4os3)
-		basic_machine=sparc-sun
-		os=-sunos3
-		;;
-	sun4os4)
-		basic_machine=sparc-sun
-		os=-sunos4
-		;;
-	sun4sol2)
-		basic_machine=sparc-sun
-		os=-solaris2
-		;;
-	sun3 | sun3-*)
-		basic_machine=m68k-sun
-		;;
-	sun4)
-		basic_machine=sparc-sun
-		;;
-	sun386 | sun386i | roadrunner)
-		basic_machine=i386-sun
-		;;
-	sv1)
-		basic_machine=sv1-cray
-		os=-unicos
-		;;
-	symmetry)
-		basic_machine=i386-sequent
-		os=-dynix
-		;;
-	t3e)
-		basic_machine=alphaev5-cray
-		os=-unicos
-		;;
-	t90)
-		basic_machine=t90-cray
-		os=-unicos
-		;;
-	tile*)
-		basic_machine=$basic_machine-unknown
-		os=-linux-gnu
-		;;
-	tx39)
-		basic_machine=mipstx39-unknown
-		;;
-	tx39el)
-		basic_machine=mipstx39el-unknown
-		;;
-	toad1)
-		basic_machine=pdp10-xkl
-		os=-tops20
-		;;
-	tower | tower-32)
-		basic_machine=m68k-ncr
-		;;
-	tpf)
-		basic_machine=s390x-ibm
-		os=-tpf
-		;;
-	udi29k)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	ultra3)
-		basic_machine=a29k-nyu
-		os=-sym1
-		;;
-	v810 | necv810)
-		basic_machine=v810-nec
-		os=-none
-		;;
-	vaxv)
-		basic_machine=vax-dec
-		os=-sysv
-		;;
-	vms)
-		basic_machine=vax-dec
-		os=-vms
-		;;
-	vpp*|vx|vx-*)
-		basic_machine=f301-fujitsu
-		;;
-	vxworks960)
-		basic_machine=i960-wrs
-		os=-vxworks
-		;;
-	vxworks68)
-		basic_machine=m68k-wrs
-		os=-vxworks
-		;;
-	vxworks29k)
-		basic_machine=a29k-wrs
-		os=-vxworks
-		;;
-	w65*)
-		basic_machine=w65-wdc
-		os=-none
-		;;
-	w89k-*)
-		basic_machine=hppa1.1-winbond
-		os=-proelf
-		;;
-	x64)
-		basic_machine=x86_64-pc
-		;;
-	xbox)
-		basic_machine=i686-pc
-		os=-mingw32
-		;;
-	xps | xps100)
-		basic_machine=xps100-honeywell
-		;;
-	xscale-* | xscalee[bl]-*)
-		basic_machine=`echo "$basic_machine" | sed 's/^xscale/arm/'`
-		;;
-	ymp)
-		basic_machine=ymp-cray
-		os=-unicos
-		;;
-	none)
-		basic_machine=none-none
-		os=-none
+	xps-unknown | xps100-unknown)
+		cpu=xps100
+		vendor=honeywell
 		;;
 
-# Here we handle the default manufacturer of certain CPU types.  It is in
-# some cases the only manufacturer, in others, it is the most popular.
-	w89k)
-		basic_machine=hppa1.1-winbond
+	# Here we normalize CPU types with a missing or matching vendor
+	dpx20-unknown | dpx20-bull)
+		cpu=rs6000
+		vendor=bull
+		basic_os=${basic_os:-bosx}
 		;;
-	op50n)
-		basic_machine=hppa1.1-oki
+
+	# Here we normalize CPU types irrespective of the vendor
+	amd64-*)
+		cpu=x86_64
 		;;
-	op60c)
-		basic_machine=hppa1.1-oki
+	blackfin-*)
+		cpu=bfin
+		basic_os=linux
 		;;
-	romp)
-		basic_machine=romp-ibm
+	c54x-*)
+		cpu=tic54x
 		;;
-	mmix)
-		basic_machine=mmix-knuth
+	c55x-*)
+		cpu=tic55x
 		;;
-	rs6000)
-		basic_machine=rs6000-ibm
+	c6x-*)
+		cpu=tic6x
 		;;
-	vax)
-		basic_machine=vax-dec
+	e500v[12]-*)
+		cpu=powerpc
+		basic_os=${basic_os}"spe"
 		;;
-	pdp11)
-		basic_machine=pdp11-dec
+	mips3*-*)
+		cpu=mips64
 		;;
-	we32k)
-		basic_machine=we32k-att
+	ms1-*)
+		cpu=mt
 		;;
-	sh[1234] | sh[24]a | sh[24]aeb | sh[34]eb | sh[1234]le | sh[23]ele)
-		basic_machine=sh-unknown
+	m68knommu-*)
+		cpu=m68k
+		basic_os=linux
 		;;
-	cydra)
-		basic_machine=cydra-cydrome
+	m9s12z-* | m68hcs12z-* | hcs12z-* | s12z-*)
+		cpu=s12z
 		;;
-	orion)
-		basic_machine=orion-highlevel
+	openrisc-*)
+		cpu=or32
 		;;
-	orion105)
-		basic_machine=clipper-highlevel
+	parisc-*)
+		cpu=hppa
+		basic_os=linux
 		;;
-	mac | mpw | mac-mpw)
-		basic_machine=m68k-apple
+	pentium-* | p5-* | k5-* | k6-* | nexgen-* | viac3-*)
+		cpu=i586
 		;;
-	pmac | pmac-mpw)
-		basic_machine=powerpc-apple
+	pentiumpro-* | p6-* | 6x86-* | athlon-* | athalon_*-*)
+		cpu=i686
 		;;
-	*-unknown)
-		# Make sure to match an already-canonicalized machine name.
+	pentiumii-* | pentium2-* | pentiumiii-* | pentium3-*)
+		cpu=i686
 		;;
+	pentium4-*)
+		cpu=i786
+		;;
+	pc98-*)
+		cpu=i386
+		;;
+	ppc-* | ppcbe-*)
+		cpu=powerpc
+		;;
+	ppcle-* | powerpclittle-*)
+		cpu=powerpcle
+		;;
+	ppc64-*)
+		cpu=powerpc64
+		;;
+	ppc64le-* | powerpc64little-*)
+		cpu=powerpc64le
+		;;
+	sb1-*)
+		cpu=mipsisa64sb1
+		;;
+	sb1el-*)
+		cpu=mipsisa64sb1el
+		;;
+	sh5e[lb]-*)
+		cpu=`echo "$cpu" | sed 's/^\(sh.\)e\(.\)$/\1\2e/'`
+		;;
+	spur-*)
+		cpu=spur
+		;;
+	strongarm-* | thumb-*)
+		cpu=arm
+		;;
+	tx39-*)
+		cpu=mipstx39
+		;;
+	tx39el-*)
+		cpu=mipstx39el
+		;;
+	x64-*)
+		cpu=x86_64
+		;;
+	xscale-* | xscalee[bl]-*)
+		cpu=`echo "$cpu" | sed 's/^xscale/arm/'`
+		;;
+	arm64-*)
+		cpu=aarch64
+		;;
+
+	# Recognize the canonical CPU Types that limit and/or modify the
+	# company names they are paired with.
+	cr16-*)
+		basic_os=${basic_os:-elf}
+		;;
+	crisv32-* | etraxfs*-*)
+		cpu=crisv32
+		vendor=axis
+		;;
+	cris-* | etrax*-*)
+		cpu=cris
+		vendor=axis
+		;;
+	crx-*)
+		basic_os=${basic_os:-elf}
+		;;
+	neo-tandem)
+		cpu=neo
+		vendor=tandem
+		;;
+	nse-tandem)
+		cpu=nse
+		vendor=tandem
+		;;
+	nsr-tandem)
+		cpu=nsr
+		vendor=tandem
+		;;
+	nsv-tandem)
+		cpu=nsv
+		vendor=tandem
+		;;
+	nsx-tandem)
+		cpu=nsx
+		vendor=tandem
+		;;
+	mipsallegrexel-sony)
+		cpu=mipsallegrexel
+		vendor=sony
+		;;
+	tile*-*)
+		basic_os=${basic_os:-linux-gnu}
+		;;
+
 	*)
-		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
-		exit 1
+		# Recognize the canonical CPU types that are allowed with any
+		# company name.
+		case $cpu in
+			1750a | 580 \
+			| a29k \
+			| aarch64 | aarch64_be \
+			| abacus \
+			| alpha | alphaev[4-8] | alphaev56 | alphaev6[78] \
+			| alpha64 | alpha64ev[4-8] | alpha64ev56 | alpha64ev6[78] \
+			| alphapca5[67] | alpha64pca5[67] \
+			| am33_2.0 \
+			| amdgcn \
+			| arc | arceb | arc32 | arc64 \
+			| arm | arm[lb]e | arme[lb] | armv* \
+			| avr | avr32 \
+			| asmjs \
+			| ba \
+			| be32 | be64 \
+			| bfin | bpf | bs2000 \
+			| c[123]* | c30 | [cjt]90 | c4x \
+			| c8051 | clipper | craynv | csky | cydra \
+			| d10v | d30v | dlx | dsp16xx \
+			| e2k | elxsi | epiphany \
+			| f30[01] | f700 | fido | fr30 | frv | ft32 | fx80 \
+			| h8300 | h8500 \
+			| hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
+			| hexagon \
+			| i370 | i*86 | i860 | i960 | ia16 | ia64 \
+			| ip2k | iq2000 \
+			| k1om \
+			| le32 | le64 \
+			| lm32 \
+			| loongarch32 | loongarch64 | loongarchx32 \
+			| m32c | m32r | m32rle \
+			| m5200 | m68000 | m680[012346]0 | m68360 | m683?2 | m68k \
+			| m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x \
+			| m88110 | m88k | maxq | mb | mcore | mep | metag \
+			| microblaze | microblazeel \
+			| mips | mipsbe | mipseb | mipsel | mipsle \
+			| mips16 \
+			| mips64 | mips64eb | mips64el \
+			| mips64octeon | mips64octeonel \
+			| mips64orion | mips64orionel \
+			| mips64r5900 | mips64r5900el \
+			| mips64vr | mips64vrel \
+			| mips64vr4100 | mips64vr4100el \
+			| mips64vr4300 | mips64vr4300el \
+			| mips64vr5000 | mips64vr5000el \
+			| mips64vr5900 | mips64vr5900el \
+			| mipsisa32 | mipsisa32el \
+			| mipsisa32r2 | mipsisa32r2el \
+			| mipsisa32r3 | mipsisa32r3el \
+			| mipsisa32r5 | mipsisa32r5el \
+			| mipsisa32r6 | mipsisa32r6el \
+			| mipsisa64 | mipsisa64el \
+			| mipsisa64r2 | mipsisa64r2el \
+			| mipsisa64r3 | mipsisa64r3el \
+			| mipsisa64r5 | mipsisa64r5el \
+			| mipsisa64r6 | mipsisa64r6el \
+			| mipsisa64sb1 | mipsisa64sb1el \
+			| mipsisa64sr71k | mipsisa64sr71kel \
+			| mipsr5900 | mipsr5900el \
+			| mipstx39 | mipstx39el \
+			| mmix \
+			| mn10200 | mn10300 \
+			| moxie \
+			| mt \
+			| msp430 \
+			| nds32 | nds32le | nds32be \
+			| nfp \
+			| nios | nios2 | nios2eb | nios2el \
+			| none | np1 | ns16k | ns32k | nvptx \
+			| open8 \
+			| or1k* \
+			| or32 \
+			| orion \
+			| picochip \
+			| pdp10 | pdp11 | pj | pjl | pn | power \
+			| powerpc | powerpc64 | powerpc64le | powerpcle | powerpcspe \
+			| pru \
+			| pyramid \
+			| riscv | riscv32 | riscv32be | riscv64 | riscv64be \
+			| rl78 | romp | rs6000 | rx \
+			| s390 | s390x \
+			| score \
+			| sh | shl \
+			| sh[1234] | sh[24]a | sh[24]ae[lb] | sh[23]e | she[lb] | sh[lb]e \
+			| sh[1234]e[lb] |  sh[12345][lb]e | sh[23]ele | sh64 | sh64le \
+			| sparc | sparc64 | sparc64b | sparc64v | sparc86x | sparclet \
+			| sparclite \
+			| sparcv8 | sparcv9 | sparcv9b | sparcv9v | sv1 | sx* \
+			| spu \
+			| tahoe \
+			| thumbv7* \
+			| tic30 | tic4x | tic54x | tic55x | tic6x | tic80 \
+			| tron \
+			| ubicom32 \
+			| v70 | v850 | v850e | v850e1 | v850es | v850e2 | v850e2v3 \
+			| vax \
+			| visium \
+			| w65 \
+			| wasm32 | wasm64 \
+			| we32k \
+			| x86 | x86_64 | xc16x | xgate | xps100 \
+			| xstormy16 | xtensa* \
+			| ymp \
+			| z8k | z80)
+				;;
+
+			*)
+				echo Invalid configuration \`"$1"\': machine \`"$cpu-$vendor"\' not recognized 1>&2
+				exit 1
+				;;
+		esac
 		;;
 esac
 
 # Here we canonicalize certain aliases for manufacturers.
-case $basic_machine in
-	*-digital*)
-		basic_machine=`echo "$basic_machine" | sed 's/digital.*/dec/'`
+case $vendor in
+	digital*)
+		vendor=dec
 		;;
-	*-commodore*)
-		basic_machine=`echo "$basic_machine" | sed 's/commodore.*/cbm/'`
+	commodore*)
+		vendor=cbm
 		;;
 	*)
 		;;
@@ -1334,203 +1301,215 @@
 
 # Decode manufacturer-specific aliases for certain operating systems.
 
-if [ x"$os" != x"" ]
+if test x$basic_os != x
 then
+
+# First recognize some ad-hoc caes, or perhaps split kernel-os, or else just
+# set os.
+case $basic_os in
+	gnu/linux*)
+		kernel=linux
+		os=`echo "$basic_os" | sed -e 's|gnu/linux|gnu|'`
+		;;
+	os2-emx)
+		kernel=os2
+		os=`echo "$basic_os" | sed -e 's|os2-emx|emx|'`
+		;;
+	nto-qnx*)
+		kernel=nto
+		os=`echo "$basic_os" | sed -e 's|nto-qnx|qnx|'`
+		;;
+	*-*)
+		# shellcheck disable=SC2162
+		saved_IFS=$IFS
+		IFS="-" read kernel os <<EOF
+$basic_os
+EOF
+		IFS=$saved_IFS
+		;;
+	# Default OS when just kernel was specified
+	nto*)
+		kernel=nto
+		os=`echo "$basic_os" | sed -e 's|nto|qnx|'`
+		;;
+	linux*)
+		kernel=linux
+		os=`echo "$basic_os" | sed -e 's|linux|gnu|'`
+		;;
+	*)
+		kernel=
+		os=$basic_os
+		;;
+esac
+
+# Now, normalize the OS (knowing we just have one component, it's not a kernel,
+# etc.)
 case $os in
 	# First match some system type aliases that might get confused
 	# with valid system types.
-	# -solaris* is a basic system type, with this one exception.
-	-auroraux)
-		os=-auroraux
+	# solaris* is a basic system type, with this one exception.
+	auroraux)
+		os=auroraux
 		;;
-	-solaris1 | -solaris1.*)
-		os=`echo $os | sed -e 's|solaris1|sunos4|'`
+	bluegene*)
+		os=cnk
 		;;
-	-solaris)
-		os=-solaris2
+	solaris1 | solaris1.*)
+		os=`echo "$os" | sed -e 's|solaris1|sunos4|'`
 		;;
-	-unixware*)
-		os=-sysv4.2uw
+	solaris)
+		os=solaris2
 		;;
-	-gnu/linux*)
-		os=`echo $os | sed -e 's|gnu/linux|linux-gnu|'`
+	unixware*)
+		os=sysv4.2uw
 		;;
 	# es1800 is here to avoid being matched by es* (a different OS)
-	-es1800*)
-		os=-ose
+	es1800*)
+		os=ose
 		;;
-	# Now accept the basic system types.
-	# The portable systems comes first.
-	# Each alternative MUST end in a * to match a version number.
-	# -sysv* is not here because it comes later, after sysvr4.
-	-gnu* | -bsd* | -mach* | -minix* | -genix* | -ultrix* | -irix* \
-	      | -*vms* | -sco* | -esix* | -isc* | -aix* | -cnk* | -sunos | -sunos[34]*\
-	      | -hpux* | -unos* | -osf* | -luna* | -dgux* | -auroraux* | -solaris* \
-	      | -sym* | -kopensolaris* | -plan9* \
-	      | -amigaos* | -amigados* | -msdos* | -newsos* | -unicos* | -aof* \
-	      | -aos* | -aros* | -cloudabi* | -sortix* \
-	      | -nindy* | -vxsim* | -vxworks* | -ebmon* | -hms* | -mvs* \
-	      | -clix* | -riscos* | -uniplus* | -iris* | -rtu* | -xenix* \
-	      | -hiux* | -knetbsd* | -mirbsd* | -netbsd* \
-	      | -bitrig* | -openbsd* | -solidbsd* | -libertybsd* \
-	      | -ekkobsd* | -kfreebsd* | -freebsd* | -riscix* | -lynxos* \
-	      | -bosx* | -nextstep* | -cxux* | -aout* | -elf* | -oabi* \
-	      | -ptx* | -coff* | -ecoff* | -winnt* | -domain* | -vsta* \
-	      | -udi* | -eabi* | -lites* | -ieee* | -go32* | -aux* | -hcos* \
-	      | -chorusos* | -chorusrdb* | -cegcc* | -glidix* \
-	      | -cygwin* | -msys* | -pe* | -psos* | -moss* | -proelf* | -rtems* \
-	      | -midipix* | -mingw32* | -mingw64* | -linux-gnu* | -linux-android* \
-	      | -linux-newlib* | -linux-musl* | -linux-uclibc* \
-	      | -uxpv* | -beos* | -mpeix* | -udk* | -moxiebox* \
-	      | -interix* | -uwin* | -mks* | -rhapsody* | -darwin* \
-	      | -openstep* | -oskit* | -conix* | -pw32* | -nonstopux* \
-	      | -storm-chaos* | -tops10* | -tenex* | -tops20* | -its* \
-	      | -os2* | -vos* | -palmos* | -uclinux* | -nucleus* \
-	      | -morphos* | -superux* | -rtmk* | -windiss* \
-	      | -powermax* | -dnix* | -nx6 | -nx7 | -sei* | -dragonfly* \
-	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops* | -es* \
-	      | -onefs* | -tirtos* | -phoenix* | -fuchsia* | -redox* | -bme* \
-	      | -midnightbsd*)
-	# Remember, each alternative MUST END IN *, to match a version number.
+	# Some version numbers need modification
+	chorusos*)
+		os=chorusos
 		;;
-	-qnx*)
-		case $basic_machine in
-		    x86-* | i*86-*)
-			;;
-		    *)
-			os=-nto$os
-			;;
-		esac
+	isc)
+		os=isc2.2
 		;;
-	-nto-qnx*)
+	sco6)
+		os=sco5v6
 		;;
-	-nto*)
-		os=`echo $os | sed -e 's|nto|nto-qnx|'`
+	sco5)
+		os=sco3.2v5
 		;;
-	-sim | -xray | -os68k* | -v88r* \
-	      | -windows* | -osx | -abug | -netware* | -os9* \
-	      | -macos* | -mpw* | -magic* | -mmixware* | -mon960* | -lnews*)
+	sco4)
+		os=sco3.2v4
 		;;
-	-mac*)
+	sco3.2.[4-9]*)
+		os=`echo "$os" | sed -e 's/sco3.2./sco3.2v/'`
+		;;
+	sco*v* | scout)
+		# Don't match below
+		;;
+	sco*)
+		os=sco3.2v2
+		;;
+	psos*)
+		os=psos
+		;;
+	qnx*)
+		os=qnx
+		;;
+	hiux*)
+		os=hiuxwe2
+		;;
+	lynx*178)
+		os=lynxos178
+		;;
+	lynx*5)
+		os=lynxos5
+		;;
+	lynxos*)
+		# don't get caught up in next wildcard
+		;;
+	lynx*)
+		os=lynxos
+		;;
+	mac[0-9]*)
 		os=`echo "$os" | sed -e 's|mac|macos|'`
 		;;
-	-linux-dietlibc)
-		os=-linux-dietlibc
+	opened*)
+		os=openedition
 		;;
-	-linux*)
-		os=`echo $os | sed -e 's|linux|linux-gnu|'`
+	os400*)
+		os=os400
 		;;
-	-sunos5*)
+	sunos5*)
 		os=`echo "$os" | sed -e 's|sunos5|solaris2|'`
 		;;
-	-sunos6*)
+	sunos6*)
 		os=`echo "$os" | sed -e 's|sunos6|solaris3|'`
 		;;
-	-opened*)
-		os=-openedition
+	wince*)
+		os=wince
 		;;
-	-os400*)
-		os=-os400
+	utek*)
+		os=bsd
 		;;
-	-wince*)
-		os=-wince
+	dynix*)
+		os=bsd
 		;;
-	-utek*)
-		os=-bsd
+	acis*)
+		os=aos
 		;;
-	-dynix*)
-		os=-bsd
+	atheos*)
+		os=atheos
 		;;
-	-acis*)
-		os=-aos
+	syllable*)
+		os=syllable
 		;;
-	-atheos*)
-		os=-atheos
+	386bsd)
+		os=bsd
 		;;
-	-syllable*)
-		os=-syllable
+	ctix* | uts*)
+		os=sysv
 		;;
-	-386bsd)
-		os=-bsd
+	nova*)
+		os=rtmk-nova
 		;;
-	-ctix* | -uts*)
-		os=-sysv
-		;;
-	-nova*)
-		os=-rtmk-nova
-		;;
-	-ns2)
-		os=-nextstep2
-		;;
-	-nsk*)
-		os=-nsk
+	ns2)
+		os=nextstep2
 		;;
 	# Preserve the version number of sinix5.
-	-sinix5.*)
-		os=`echo $os | sed -e 's|sinix|sysv|'`
+	sinix5.*)
+		os=`echo "$os" | sed -e 's|sinix|sysv|'`
 		;;
-	-sinix*)
-		os=-sysv4
+	sinix*)
+		os=sysv4
 		;;
-	-tpf*)
-		os=-tpf
+	tpf*)
+		os=tpf
 		;;
-	-triton*)
-		os=-sysv3
+	triton*)
+		os=sysv3
 		;;
-	-oss*)
-		os=-sysv3
+	oss*)
+		os=sysv3
 		;;
-	-svr4*)
-		os=-sysv4
+	svr4*)
+		os=sysv4
 		;;
-	-svr3)
-		os=-sysv3
+	svr3)
+		os=sysv3
 		;;
-	-sysvr4)
-		os=-sysv4
+	sysvr4)
+		os=sysv4
 		;;
-	# This must come after -sysvr4.
-	-sysv*)
+	ose*)
+		os=ose
 		;;
-	-ose*)
-		os=-ose
+	*mint | mint[0-9]* | *MiNT | MiNT[0-9]*)
+		os=mint
 		;;
-	-*mint | -mint[0-9]* | -*MiNT | -MiNT[0-9]*)
-		os=-mint
+	dicos*)
+		os=dicos
 		;;
-	-zvmoe)
-		os=-zvmoe
-		;;
-	-dicos*)
-		os=-dicos
-		;;
-	-pikeos*)
+	pikeos*)
 		# Until real need of OS specific support for
 		# particular features comes up, bare metal
 		# configurations are quite functional.
-		case $basic_machine in
+		case $cpu in
 		    arm*)
-			os=-eabi
+			os=eabi
 			;;
 		    *)
-			os=-elf
+			os=elf
 			;;
 		esac
 		;;
-	-nacl*)
-		;;
-	-ios)
-		;;
-	-none)
-		;;
 	*)
-		# Get rid of the `-' at the beginning of $os.
-		os=`echo $os | sed 's/[^-]*-//'`
-		echo Invalid configuration \`"$1"\': system \`"$os"\' not recognized 1>&2
-		exit 1
+		# No normalization, but not necessarily accepted, that comes below.
 		;;
 esac
+
 else
 
 # Here we handle the default operating systems that come with various machines.
@@ -1543,254 +1522,358 @@
 # will signal an error saying that MANUFACTURER isn't an operating
 # system, and we'll never get to this point.
 
-case $basic_machine in
+kernel=
+case $cpu-$vendor in
 	score-*)
-		os=-elf
+		os=elf
 		;;
 	spu-*)
-		os=-elf
+		os=elf
 		;;
 	*-acorn)
-		os=-riscix1.2
+		os=riscix1.2
 		;;
 	arm*-rebel)
-		os=-linux
+		kernel=linux
+		os=gnu
 		;;
 	arm*-semi)
-		os=-aout
+		os=aout
 		;;
 	c4x-* | tic4x-*)
-		os=-coff
+		os=coff
 		;;
 	c8051-*)
-		os=-elf
+		os=elf
+		;;
+	clipper-intergraph)
+		os=clix
 		;;
 	hexagon-*)
-		os=-elf
+		os=elf
 		;;
 	tic54x-*)
-		os=-coff
+		os=coff
 		;;
 	tic55x-*)
-		os=-coff
+		os=coff
 		;;
 	tic6x-*)
-		os=-coff
+		os=coff
 		;;
 	# This must come before the *-dec entry.
 	pdp10-*)
-		os=-tops20
+		os=tops20
 		;;
 	pdp11-*)
-		os=-none
+		os=none
 		;;
 	*-dec | vax-*)
-		os=-ultrix4.2
+		os=ultrix4.2
 		;;
 	m68*-apollo)
-		os=-domain
+		os=domain
 		;;
 	i386-sun)
-		os=-sunos4.0.2
+		os=sunos4.0.2
 		;;
 	m68000-sun)
-		os=-sunos3
+		os=sunos3
 		;;
 	m68*-cisco)
-		os=-aout
+		os=aout
 		;;
 	mep-*)
-		os=-elf
+		os=elf
 		;;
 	mips*-cisco)
-		os=-elf
+		os=elf
 		;;
 	mips*-*)
-		os=-elf
+		os=elf
 		;;
 	or32-*)
-		os=-coff
+		os=coff
 		;;
 	*-tti)	# must be before sparc entry or we get the wrong os.
-		os=-sysv3
+		os=sysv3
 		;;
 	sparc-* | *-sun)
-		os=-sunos4.1.1
+		os=sunos4.1.1
 		;;
 	pru-*)
-		os=-elf
+		os=elf
 		;;
 	*-be)
-		os=-beos
+		os=beos
 		;;
 	*-ibm)
-		os=-aix
+		os=aix
 		;;
 	*-knuth)
-		os=-mmixware
+		os=mmixware
 		;;
 	*-wec)
-		os=-proelf
+		os=proelf
 		;;
 	*-winbond)
-		os=-proelf
+		os=proelf
 		;;
 	*-oki)
-		os=-proelf
+		os=proelf
 		;;
 	*-hp)
-		os=-hpux
+		os=hpux
 		;;
 	*-hitachi)
-		os=-hiux
+		os=hiux
 		;;
 	i860-* | *-att | *-ncr | *-altos | *-motorola | *-convergent)
-		os=-sysv
+		os=sysv
 		;;
 	*-cbm)
-		os=-amigaos
+		os=amigaos
 		;;
 	*-dg)
-		os=-dgux
+		os=dgux
 		;;
 	*-dolphin)
-		os=-sysv3
+		os=sysv3
 		;;
 	m68k-ccur)
-		os=-rtu
+		os=rtu
 		;;
 	m88k-omron*)
-		os=-luna
+		os=luna
 		;;
 	*-next)
-		os=-nextstep
+		os=nextstep
 		;;
 	*-sequent)
-		os=-ptx
+		os=ptx
 		;;
 	*-crds)
-		os=-unos
+		os=unos
 		;;
 	*-ns)
-		os=-genix
+		os=genix
 		;;
 	i370-*)
-		os=-mvs
+		os=mvs
 		;;
 	*-gould)
-		os=-sysv
+		os=sysv
 		;;
 	*-highlevel)
-		os=-bsd
+		os=bsd
 		;;
 	*-encore)
-		os=-bsd
+		os=bsd
 		;;
 	*-sgi)
-		os=-irix
+		os=irix
 		;;
 	*-siemens)
-		os=-sysv4
+		os=sysv4
 		;;
 	*-masscomp)
-		os=-rtu
+		os=rtu
 		;;
 	f30[01]-fujitsu | f700-fujitsu)
-		os=-uxpv
+		os=uxpv
 		;;
 	*-rom68k)
-		os=-coff
+		os=coff
 		;;
 	*-*bug)
-		os=-coff
+		os=coff
 		;;
 	*-apple)
-		os=-macos
+		os=macos
 		;;
 	*-atari*)
-		os=-mint
+		os=mint
+		;;
+	*-wrs)
+		os=vxworks
 		;;
 	*)
-		os=-none
+		os=none
 		;;
 esac
+
 fi
 
+# Now, validate our (potentially fixed-up) OS.
+case $os in
+	# Sometimes we do "kernel-libc", so those need to count as OSes.
+	musl* | newlib* | relibc* | uclibc*)
+		;;
+	# Likewise for "kernel-abi"
+	eabi* | gnueabi*)
+		;;
+	# VxWorks passes extra cpu info in the 4th filed.
+	simlinux | simwindows | spe)
+		;;
+	# Now accept the basic system types.
+	# The portable systems comes first.
+	# Each alternative MUST end in a * to match a version number.
+	gnu* | android* | bsd* | mach* | minix* | genix* | ultrix* | irix* \
+	     | *vms* | esix* | aix* | cnk* | sunos | sunos[34]* \
+	     | hpux* | unos* | osf* | luna* | dgux* | auroraux* | solaris* \
+	     | sym* |  plan9* | psp* | sim* | xray* | os68k* | v88r* \
+	     | hiux* | abug | nacl* | netware* | windows* \
+	     | os9* | macos* | osx* | ios* \
+	     | mpw* | magic* | mmixware* | mon960* | lnews* \
+	     | amigaos* | amigados* | msdos* | newsos* | unicos* | aof* \
+	     | aos* | aros* | cloudabi* | sortix* | twizzler* \
+	     | nindy* | vxsim* | vxworks* | ebmon* | hms* | mvs* \
+	     | clix* | riscos* | uniplus* | iris* | isc* | rtu* | xenix* \
+	     | mirbsd* | netbsd* | dicos* | openedition* | ose* \
+	     | bitrig* | openbsd* | secbsd* | solidbsd* | libertybsd* | os108* \
+	     | ekkobsd* | freebsd* | riscix* | lynxos* | os400* \
+	     | bosx* | nextstep* | cxux* | aout* | elf* | oabi* \
+	     | ptx* | coff* | ecoff* | winnt* | domain* | vsta* \
+	     | udi* | lites* | ieee* | go32* | aux* | hcos* \
+	     | chorusrdb* | cegcc* | glidix* | serenity* \
+	     | cygwin* | msys* | pe* | moss* | proelf* | rtems* \
+	     | midipix* | mingw32* | mingw64* | mint* \
+	     | uxpv* | beos* | mpeix* | udk* | moxiebox* \
+	     | interix* | uwin* | mks* | rhapsody* | darwin* \
+	     | openstep* | oskit* | conix* | pw32* | nonstopux* \
+	     | storm-chaos* | tops10* | tenex* | tops20* | its* \
+	     | os2* | vos* | palmos* | uclinux* | nucleus* | morphos* \
+	     | scout* | superux* | sysv* | rtmk* | tpf* | windiss* \
+	     | powermax* | dnix* | nx6 | nx7 | sei* | dragonfly* \
+	     | skyos* | haiku* | rdos* | toppers* | drops* | es* \
+	     | onefs* | tirtos* | phoenix* | fuchsia* | redox* | bme* \
+	     | midnightbsd* | amdhsa* | unleashed* | emscripten* | wasi* \
+	     | nsk* | powerunix* | genode* | zvmoe* | qnx* | emx* | zephyr*)
+		;;
+	# This one is extra strict with allowed versions
+	sco3.2v2 | sco3.2v[4-9]* | sco5v6*)
+		# Don't forget version if it is 3.2v4 or newer.
+		;;
+	none)
+		;;
+	*)
+		echo Invalid configuration \`"$1"\': OS \`"$os"\' not recognized 1>&2
+		exit 1
+		;;
+esac
+
+# As a final step for OS-related things, validate the OS-kernel combination
+# (given a valid OS), if there is a kernel.
+case $kernel-$os in
+	linux-gnu* | linux-dietlibc* | linux-android* | linux-newlib* \
+		   | linux-musl* | linux-relibc* | linux-uclibc* )
+		;;
+	uclinux-uclibc* )
+		;;
+	-dietlibc* | -newlib* | -musl* | -relibc* | -uclibc* )
+		# These are just libc implementations, not actual OSes, and thus
+		# require a kernel.
+		echo "Invalid configuration \`$1': libc \`$os' needs explicit kernel." 1>&2
+		exit 1
+		;;
+	kfreebsd*-gnu* | kopensolaris*-gnu*)
+		;;
+	vxworks-simlinux | vxworks-simwindows | vxworks-spe)
+		;;
+	nto-qnx*)
+		;;
+	os2-emx)
+		;;
+	*-eabi* | *-gnueabi*)
+		;;
+	-*)
+		# Blank kernel with real OS is always fine.
+		;;
+	*-*)
+		echo "Invalid configuration \`$1': Kernel \`$kernel' not known to work with OS \`$os'." 1>&2
+		exit 1
+		;;
+esac
+
 # Here we handle the case where we know the os, and the CPU type, but not the
 # manufacturer.  We pick the logical manufacturer.
-vendor=unknown
-case $basic_machine in
-	*-unknown)
-		case $os in
-			-riscix*)
+case $vendor in
+	unknown)
+		case $cpu-$os in
+			*-riscix*)
 				vendor=acorn
 				;;
-			-sunos*)
+			*-sunos*)
 				vendor=sun
 				;;
-			-cnk*|-aix*)
+			*-cnk* | *-aix*)
 				vendor=ibm
 				;;
-			-beos*)
+			*-beos*)
 				vendor=be
 				;;
-			-hpux*)
+			*-hpux*)
 				vendor=hp
 				;;
-			-mpeix*)
+			*-mpeix*)
 				vendor=hp
 				;;
-			-hiux*)
+			*-hiux*)
 				vendor=hitachi
 				;;
-			-unos*)
+			*-unos*)
 				vendor=crds
 				;;
-			-dgux*)
+			*-dgux*)
 				vendor=dg
 				;;
-			-luna*)
+			*-luna*)
 				vendor=omron
 				;;
-			-genix*)
+			*-genix*)
 				vendor=ns
 				;;
-			-mvs* | -opened*)
+			*-clix*)
+				vendor=intergraph
+				;;
+			*-mvs* | *-opened*)
 				vendor=ibm
 				;;
-			-os400*)
+			*-os400*)
 				vendor=ibm
 				;;
-			-ptx*)
+			s390-* | s390x-*)
+				vendor=ibm
+				;;
+			*-ptx*)
 				vendor=sequent
 				;;
-			-tpf*)
+			*-tpf*)
 				vendor=ibm
 				;;
-			-vxsim* | -vxworks* | -windiss*)
+			*-vxsim* | *-vxworks* | *-windiss*)
 				vendor=wrs
 				;;
-			-aux*)
+			*-aux*)
 				vendor=apple
 				;;
-			-hms*)
+			*-hms*)
 				vendor=hitachi
 				;;
-			-mpw* | -macos*)
+			*-mpw* | *-macos*)
 				vendor=apple
 				;;
-			-*mint | -mint[0-9]* | -*MiNT | -MiNT[0-9]*)
+			*-*mint | *-mint[0-9]* | *-*MiNT | *-MiNT[0-9]*)
 				vendor=atari
 				;;
-			-vos*)
+			*-vos*)
 				vendor=stratus
 				;;
 		esac
-		basic_machine=`echo "$basic_machine" | sed "s/unknown/$vendor/"`
 		;;
 esac
 
-echo "$basic_machine$os"
+echo "$cpu-$vendor-${kernel:+$kernel-}$os"
 exit
 
 # Local variables:
diff --git a/configure b/configure
index 1b2c463..b66bb11 100755
--- a/configure
+++ b/configure
@@ -1,11 +1,12 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for libpng 1.6.37.
+# Generated by GNU Autoconf 2.71 for libpng 1.6.38.
 #
 # Report bugs to <png-mng-implement@lists.sourceforge.net>.
 #
 #
-# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
+# Copyright (C) 1992-1996, 1998-2017, 2020-2021 Free Software Foundation,
+# Inc.
 #
 #
 # This configure script is free software; the Free Software Foundation
@@ -16,14 +17,16 @@
 
 # Be more Bourne compatible
 DUALCASE=1; export DUALCASE # for MKS sh
-if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then :
+as_nop=:
+if test ${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on ${1+"$@"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '${1+"$@"}'='"$@"'
   setopt NO_GLOB_SUBST
-else
+else $as_nop
   case `(set -o) 2>/dev/null` in #(
   *posix*) :
     set -o posix ;; #(
@@ -33,46 +36,46 @@
 fi
 
 
+
+# Reset variables that may have inherited troublesome values from
+# the environment.
+
+# IFS needs to be set, to space, tab, and newline, in precisely that order.
+# (If _AS_PATH_WALK were called with IFS unset, it would have the
+# side effect of setting IFS to empty, thus disabling word splitting.)
+# Quoting is to prevent editors from complaining about space-tab.
 as_nl='
 '
 export as_nl
-# Printing a long string crashes Solaris 7 /usr/bin/printf.
-as_echo='\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo$as_echo
-# Prefer a ksh shell builtin over an external printf program on Solaris,
-# but without wasting forks for bash or zsh.
-if test -z "$BASH_VERSION$ZSH_VERSION" \
-    && (test "X`print -r -- $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='print -r --'
-  as_echo_n='print -rn --'
-elif (test "X`printf %s $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='printf %s\n'
-  as_echo_n='printf %s'
-else
-  if test "X`(/usr/ucb/echo -n -n $as_echo) 2>/dev/null`" = "X-n $as_echo"; then
-    as_echo_body='eval /usr/ucb/echo -n "$1$as_nl"'
-    as_echo_n='/usr/ucb/echo -n'
-  else
-    as_echo_body='eval expr "X$1" : "X\\(.*\\)"'
-    as_echo_n_body='eval
-      arg=$1;
-      case $arg in #(
-      *"$as_nl"*)
-	expr "X$arg" : "X\\(.*\\)$as_nl";
-	arg=`expr "X$arg" : ".*$as_nl\\(.*\\)"`;;
-      esac;
-      expr "X$arg" : "X\\(.*\\)" | tr -d "$as_nl"
-    '
-    export as_echo_n_body
-    as_echo_n='sh -c $as_echo_n_body as_echo'
-  fi
-  export as_echo_body
-  as_echo='sh -c $as_echo_body as_echo'
-fi
+IFS=" ""	$as_nl"
+
+PS1='$ '
+PS2='> '
+PS4='+ '
+
+# Ensure predictable behavior from utilities with locale-dependent output.
+LC_ALL=C
+export LC_ALL
+LANGUAGE=C
+export LANGUAGE
+
+# We cannot yet rely on "unset" to work, but we need these variables
+# to be unset--not just set to an empty or harmless value--now, to
+# avoid bugs in old shells (e.g. pre-3.0 UWIN ksh).  This construct
+# also avoids known problems related to "unset" and subshell syntax
+# in other old shells (e.g. bash 2.01 and pdksh 5.2.14).
+for as_var in BASH_ENV ENV MAIL MAILPATH CDPATH
+do eval test \${$as_var+y} \
+  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
+done
+
+# Ensure that fds 0, 1, and 2 are open.
+if (exec 3>&0) 2>/dev/null; then :; else exec 0</dev/null; fi
+if (exec 3>&1) 2>/dev/null; then :; else exec 1>/dev/null; fi
+if (exec 3>&2)            ; then :; else exec 2>/dev/null; fi
 
 # The user is always right.
-if test "${PATH_SEPARATOR+set}" != set; then
+if ${PATH_SEPARATOR+false} :; then
   PATH_SEPARATOR=:
   (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 && {
     (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 ||
@@ -81,13 +84,6 @@
 fi
 
 
-# IFS
-# We need space, tab and new line, in precisely that order.  Quoting is
-# there to prevent editors from complaining about space-tab.
-# (If _AS_PATH_WALK were called with IFS unset, it would disable word
-# splitting by setting IFS to empty value.)
-IFS=" ""	$as_nl"
-
 # Find who we are.  Look in the path if we contain no directory separator.
 as_myself=
 case $0 in #((
@@ -96,8 +92,12 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    test -r "$as_dir/$0" && as_myself=$as_dir/$0 && break
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    test -r "$as_dir$0" && as_myself=$as_dir$0 && break
   done
 IFS=$as_save_IFS
 
@@ -109,30 +109,10 @@
   as_myself=$0
 fi
 if test ! -f "$as_myself"; then
-  $as_echo "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
+  printf "%s\n" "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
   exit 1
 fi
 
-# Unset variables that we do not need and which cause bugs (e.g. in
-# pre-3.0 UWIN ksh).  But do not cause bugs in bash 2.01; the "|| exit 1"
-# suppresses any "Segmentation fault" message there.  '((' could
-# trigger a bug in pdksh 5.2.14.
-for as_var in BASH_ENV ENV MAIL MAILPATH
-do eval test x\${$as_var+set} = xset \
-  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
-done
-PS1='$ '
-PS2='> '
-PS4='+ '
-
-# NLS nuisances.
-LC_ALL=C
-export LC_ALL
-LANGUAGE=C
-export LANGUAGE
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
 
 # Use a proper internal environment variable to ensure we don't fall
   # into an infinite loop, continuously re-executing ourselves.
@@ -154,20 +134,22 @@
 exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
 # Admittedly, this is quite paranoid, since all the known shells bail
 # out after a failed `exec'.
-$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
-as_fn_exit 255
+printf "%s\n" "$0: could not re-execute with $CONFIG_SHELL" >&2
+exit 255
   fi
   # We don't want this to propagate to other subprocesses.
           { _as_can_reexec=; unset _as_can_reexec;}
 if test "x$CONFIG_SHELL" = x; then
-  as_bourne_compatible="if test -n \"\${ZSH_VERSION+set}\" && (emulate sh) >/dev/null 2>&1; then :
+  as_bourne_compatible="as_nop=:
+if test \${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on \${1+\"\$@\"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '\${1+\"\$@\"}'='\"\$@\"'
   setopt NO_GLOB_SUBST
-else
+else \$as_nop
   case \`(set -o) 2>/dev/null\` in #(
   *posix*) :
     set -o posix ;; #(
@@ -187,12 +169,15 @@
 as_fn_failure && { exitcode=1; echo as_fn_failure succeeded.; }
 as_fn_ret_success || { exitcode=1; echo as_fn_ret_success failed.; }
 as_fn_ret_failure && { exitcode=1; echo as_fn_ret_failure succeeded.; }
-if ( set x; as_fn_ret_success y && test x = \"\$1\" ); then :
+if ( set x; as_fn_ret_success y && test x = \"\$1\" )
+then :
 
-else
+else \$as_nop
   exitcode=1; echo positional parameters were not saved.
 fi
 test x\$exitcode = x0 || exit 1
+blah=\$(echo \$(echo blah))
+test x\"\$blah\" = xblah || exit 1
 test -x / || exit 1"
   as_suggested="  as_lineno_1=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_1a=\$LINENO
   as_lineno_2=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_2a=\$LINENO
@@ -207,30 +192,38 @@
     PATH=/empty FPATH=/empty; export PATH FPATH
     test \"X\`printf %s \$ECHO\`\" = \"X\$ECHO\" \\
       || test \"X\`print -r -- \$ECHO\`\" = \"X\$ECHO\" ) || exit 1"
-  if (eval "$as_required") 2>/dev/null; then :
+  if (eval "$as_required") 2>/dev/null
+then :
   as_have_required=yes
-else
+else $as_nop
   as_have_required=no
 fi
-  if test x$as_have_required = xyes && (eval "$as_suggested") 2>/dev/null; then :
+  if test x$as_have_required = xyes && (eval "$as_suggested") 2>/dev/null
+then :
 
-else
+else $as_nop
   as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 as_found=false
 for as_dir in /bin$PATH_SEPARATOR/usr/bin$PATH_SEPARATOR$PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
   as_found=:
   case $as_dir in #(
 	 /*)
 	   for as_base in sh bash ksh sh5; do
 	     # Try only shells that exist, to save several forks.
-	     as_shell=$as_dir/$as_base
+	     as_shell=$as_dir$as_base
 	     if { test -f "$as_shell" || test -f "$as_shell.exe"; } &&
-		    { $as_echo "$as_bourne_compatible""$as_required" | as_run=a "$as_shell"; } 2>/dev/null; then :
+		    as_run=a "$as_shell" -c "$as_bourne_compatible""$as_required" 2>/dev/null
+then :
   CONFIG_SHELL=$as_shell as_have_required=yes
-		   if { $as_echo "$as_bourne_compatible""$as_suggested" | as_run=a "$as_shell"; } 2>/dev/null; then :
+		   if as_run=a "$as_shell" -c "$as_bourne_compatible""$as_suggested" 2>/dev/null
+then :
   break 2
 fi
 fi
@@ -238,14 +231,21 @@
        esac
   as_found=false
 done
-$as_found || { if { test -f "$SHELL" || test -f "$SHELL.exe"; } &&
-	      { $as_echo "$as_bourne_compatible""$as_required" | as_run=a "$SHELL"; } 2>/dev/null; then :
-  CONFIG_SHELL=$SHELL as_have_required=yes
-fi; }
 IFS=$as_save_IFS
+if $as_found
+then :
+
+else $as_nop
+  if { test -f "$SHELL" || test -f "$SHELL.exe"; } &&
+	      as_run=a "$SHELL" -c "$as_bourne_compatible""$as_required" 2>/dev/null
+then :
+  CONFIG_SHELL=$SHELL as_have_required=yes
+fi
+fi
 
 
-      if test "x$CONFIG_SHELL" != x; then :
+      if test "x$CONFIG_SHELL" != x
+then :
   export CONFIG_SHELL
              # We cannot yet assume a decent shell, so we have to provide a
 # neutralization value for shells without unset; and this also
@@ -263,18 +263,19 @@
 exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
 # Admittedly, this is quite paranoid, since all the known shells bail
 # out after a failed `exec'.
-$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
+printf "%s\n" "$0: could not re-execute with $CONFIG_SHELL" >&2
 exit 255
 fi
 
-    if test x$as_have_required = xno; then :
-  $as_echo "$0: This script requires a shell more modern than all"
-  $as_echo "$0: the shells that I found on your system."
-  if test x${ZSH_VERSION+set} = xset ; then
-    $as_echo "$0: In particular, zsh $ZSH_VERSION has bugs and should"
-    $as_echo "$0: be upgraded to zsh 4.3.4 or later."
+    if test x$as_have_required = xno
+then :
+  printf "%s\n" "$0: This script requires a shell more modern than all"
+  printf "%s\n" "$0: the shells that I found on your system."
+  if test ${ZSH_VERSION+y} ; then
+    printf "%s\n" "$0: In particular, zsh $ZSH_VERSION has bugs and should"
+    printf "%s\n" "$0: be upgraded to zsh 4.3.4 or later."
   else
-    $as_echo "$0: Please tell bug-autoconf@gnu.org and
+    printf "%s\n" "$0: Please tell bug-autoconf@gnu.org and
 $0: png-mng-implement@lists.sourceforge.net about your
 $0: system, including any error possibly output before this
 $0: message. Then install a modern shell, or manually run
@@ -302,6 +303,7 @@
 }
 as_unset=as_fn_unset
 
+
 # as_fn_set_status STATUS
 # -----------------------
 # Set $? to STATUS, without forking.
@@ -319,6 +321,14 @@
   as_fn_set_status $1
   exit $1
 } # as_fn_exit
+# as_fn_nop
+# ---------
+# Do nothing but, unlike ":", preserve the value of $?.
+as_fn_nop ()
+{
+  return $?
+}
+as_nop=as_fn_nop
 
 # as_fn_mkdir_p
 # -------------
@@ -333,7 +343,7 @@
     as_dirs=
     while :; do
       case $as_dir in #(
-      *\'*) as_qdir=`$as_echo "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
+      *\'*) as_qdir=`printf "%s\n" "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
       *) as_qdir=$as_dir;;
       esac
       as_dirs="'$as_qdir' $as_dirs"
@@ -342,7 +352,7 @@
 	 X"$as_dir" : 'X\(//\)[^/]' \| \
 	 X"$as_dir" : 'X\(//\)$' \| \
 	 X"$as_dir" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_dir" |
+printf "%s\n" X"$as_dir" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -381,12 +391,13 @@
 # advantage of any shell optimizations that allow amortized linear growth over
 # repeated appends, instead of the typical quadratic growth present in naive
 # implementations.
-if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null; then :
+if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null
+then :
   eval 'as_fn_append ()
   {
     eval $1+=\$2
   }'
-else
+else $as_nop
   as_fn_append ()
   {
     eval $1=\$$1\$2
@@ -398,18 +409,27 @@
 # Perform arithmetic evaluation on the ARGs, and store the result in the
 # global $as_val. Take advantage of shells that can avoid forks. The arguments
 # must be portable across $(()) and expr.
-if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null; then :
+if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null
+then :
   eval 'as_fn_arith ()
   {
     as_val=$(( $* ))
   }'
-else
+else $as_nop
   as_fn_arith ()
   {
     as_val=`expr "$@" || test $? -eq 1`
   }
 fi # as_fn_arith
 
+# as_fn_nop
+# ---------
+# Do nothing but, unlike ":", preserve the value of $?.
+as_fn_nop ()
+{
+  return $?
+}
+as_nop=as_fn_nop
 
 # as_fn_error STATUS ERROR [LINENO LOG_FD]
 # ----------------------------------------
@@ -421,9 +441,9 @@
   as_status=$1; test $as_status -eq 0 && as_status=1
   if test "$4"; then
     as_lineno=${as_lineno-"$3"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-    $as_echo "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
   fi
-  $as_echo "$as_me: error: $2" >&2
+  printf "%s\n" "$as_me: error: $2" >&2
   as_fn_exit $as_status
 } # as_fn_error
 
@@ -450,7 +470,7 @@
 $as_expr X/"$0" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$0" : 'X\(//\)$' \| \
 	 X"$0" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$0" |
+printf "%s\n" X/"$0" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -494,7 +514,7 @@
       s/-\n.*//
     ' >$as_me.lineno &&
   chmod +x "$as_me.lineno" ||
-    { $as_echo "$as_me: error: cannot create $as_me.lineno; rerun with a POSIX shell" >&2; as_fn_exit 1; }
+    { printf "%s\n" "$as_me: error: cannot create $as_me.lineno; rerun with a POSIX shell" >&2; as_fn_exit 1; }
 
   # If we had to re-execute with $CONFIG_SHELL, we're ensured to have
   # already done that, so ensure we don't try to do so again and fall
@@ -508,6 +528,10 @@
   exit
 }
 
+
+# Determine whether it's possible to make 'echo' print without a newline.
+# These variables are no longer used directly by Autoconf, but are AC_SUBSTed
+# for compatibility with existing Makefiles.
 ECHO_C= ECHO_N= ECHO_T=
 case `echo -n x` in #(((((
 -n*)
@@ -521,6 +545,13 @@
   ECHO_N='-n';;
 esac
 
+# For backward compatibility with old third-party macros, we provide
+# the shell variables $as_echo and $as_echo_n.  New code should use
+# AS_ECHO(["message"]) and AS_ECHO_N(["message"]), respectively.
+as_echo='printf %s\n'
+as_echo_n='printf %s'
+
+
 rm -f conf$$ conf$$.exe conf$$.file
 if test -d conf$$.dir; then
   rm -f conf$$.dir/conf$$.file
@@ -590,51 +621,48 @@
 # Identity of this package.
 PACKAGE_NAME='libpng'
 PACKAGE_TARNAME='libpng'
-PACKAGE_VERSION='1.6.37'
-PACKAGE_STRING='libpng 1.6.37'
+PACKAGE_VERSION='1.6.38'
+PACKAGE_STRING='libpng 1.6.38'
 PACKAGE_BUGREPORT='png-mng-implement@lists.sourceforge.net'
 PACKAGE_URL=''
 
 ac_unique_file="pngget.c"
 # Factoring default headers for most tests.
 ac_includes_default="\
-#include <stdio.h>
-#ifdef HAVE_SYS_TYPES_H
-# include <sys/types.h>
+#include <stddef.h>
+#ifdef HAVE_STDIO_H
+# include <stdio.h>
 #endif
-#ifdef HAVE_SYS_STAT_H
-# include <sys/stat.h>
-#endif
-#ifdef STDC_HEADERS
+#ifdef HAVE_STDLIB_H
 # include <stdlib.h>
-# include <stddef.h>
-#else
-# ifdef HAVE_STDLIB_H
-#  include <stdlib.h>
-# endif
 #endif
 #ifdef HAVE_STRING_H
-# if !defined STDC_HEADERS && defined HAVE_MEMORY_H
-#  include <memory.h>
-# endif
 # include <string.h>
 #endif
-#ifdef HAVE_STRINGS_H
-# include <strings.h>
-#endif
 #ifdef HAVE_INTTYPES_H
 # include <inttypes.h>
 #endif
 #ifdef HAVE_STDINT_H
 # include <stdint.h>
 #endif
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
 #ifdef HAVE_UNISTD_H
 # include <unistd.h>
 #endif"
 
+ac_header_c_list=
 ac_subst_vars='am__EXEEXT_FALSE
 am__EXEEXT_TRUE
 LTLIBOBJS
+LIBOBJS
 PNG_POWERPC_VSX_FALSE
 PNG_POWERPC_VSX_TRUE
 PNG_INTEL_SSE_FALSE
@@ -665,8 +693,6 @@
 HAVE_SOLARIS_LD_TRUE
 HAVE_CLOCK_GETTIME_FALSE
 HAVE_CLOCK_GETTIME_TRUE
-LIBOBJS
-POW_LIB
 PNG_COPTS
 DFNCPP
 LT_SYS_LIBRARY_PATH
@@ -679,6 +705,7 @@
 RANLIB
 ac_ct_AR
 AR
+FILECMD
 NM
 ac_ct_DUMPBIN
 DUMPBIN
@@ -729,6 +756,9 @@
 AM_DEFAULT_VERBOSITY
 AM_DEFAULT_V
 AM_V
+CSCOPE
+ETAGS
+CTAGS
 am__untar
 am__tar
 AMTAR
@@ -771,6 +801,7 @@
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -870,6 +901,7 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -899,8 +931,6 @@
   *)    ac_optarg=yes ;;
   esac
 
-  # Accept the important Cygnus configure options, so we can diagnose typos.
-
   case $ac_dashdash$ac_option in
   --)
     ac_dashdash=yes ;;
@@ -941,9 +971,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*disable-\(.*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid feature name: $ac_useropt"
+      as_fn_error $? "invalid feature name: \`$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "enable_$ac_useropt"
@@ -967,9 +997,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*enable-\([^=]*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid feature name: $ac_useropt"
+      as_fn_error $? "invalid feature name: \`$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "enable_$ac_useropt"
@@ -1122,6 +1152,15 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1171,9 +1210,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*with-\([^=]*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid package name: $ac_useropt"
+      as_fn_error $? "invalid package name: \`$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "with_$ac_useropt"
@@ -1187,9 +1226,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*without-\(.*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid package name: $ac_useropt"
+      as_fn_error $? "invalid package name: \`$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "with_$ac_useropt"
@@ -1233,9 +1272,9 @@
 
   *)
     # FIXME: should be removed in autoconf 3.0.
-    $as_echo "$as_me: WARNING: you should use --build, --host, --target" >&2
+    printf "%s\n" "$as_me: WARNING: you should use --build, --host, --target" >&2
     expr "x$ac_option" : ".*[^-._$as_cr_alnum]" >/dev/null &&
-      $as_echo "$as_me: WARNING: invalid host type: $ac_option" >&2
+      printf "%s\n" "$as_me: WARNING: invalid host type: $ac_option" >&2
     : "${build_alias=$ac_option} ${host_alias=$ac_option} ${target_alias=$ac_option}"
     ;;
 
@@ -1251,7 +1290,7 @@
   case $enable_option_checking in
     no) ;;
     fatal) as_fn_error $? "unrecognized options: $ac_unrecognized_opts" ;;
-    *)     $as_echo "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2 ;;
+    *)     printf "%s\n" "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2 ;;
   esac
 fi
 
@@ -1259,7 +1298,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1315,7 +1354,7 @@
 	 X"$as_myself" : 'X\(//\)[^/]' \| \
 	 X"$as_myself" : 'X\(//\)$' \| \
 	 X"$as_myself" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_myself" |
+printf "%s\n" X"$as_myself" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -1372,7 +1411,7 @@
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures libpng 1.6.37 to adapt to many kinds of systems.
+\`configure' configures libpng 1.6.38 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1412,6 +1451,7 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -1442,7 +1482,7 @@
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of libpng 1.6.37:";;
+     short | recursive ) echo "Configuration of libpng 1.6.38:";;
    esac
   cat <<\_ACEOF
 
@@ -1575,9 +1615,9 @@
 case "$ac_dir" in
 .) ac_dir_suffix= ac_top_builddir_sub=. ac_top_build_prefix= ;;
 *)
-  ac_dir_suffix=/`$as_echo "$ac_dir" | sed 's|^\.[\\/]||'`
+  ac_dir_suffix=/`printf "%s\n" "$ac_dir" | sed 's|^\.[\\/]||'`
   # A ".." for each directory in $ac_dir_suffix.
-  ac_top_builddir_sub=`$as_echo "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
+  ac_top_builddir_sub=`printf "%s\n" "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
   case $ac_top_builddir_sub in
   "") ac_top_builddir_sub=. ac_top_build_prefix= ;;
   *)  ac_top_build_prefix=$ac_top_builddir_sub/ ;;
@@ -1605,7 +1645,8 @@
 ac_abs_srcdir=$ac_abs_top_srcdir$ac_dir_suffix
 
     cd "$ac_dir" || { ac_status=$?; continue; }
-    # Check for guested configure.
+    # Check for configure.gnu first; this name is used for a wrapper for
+    # Metaconfig's "Configure" on case-insensitive file systems.
     if test -f "$ac_srcdir/configure.gnu"; then
       echo &&
       $SHELL "$ac_srcdir/configure.gnu" --help=recursive
@@ -1613,7 +1654,7 @@
       echo &&
       $SHELL "$ac_srcdir/configure" --help=recursive
     else
-      $as_echo "$as_me: WARNING: no configuration information is in $ac_dir" >&2
+      printf "%s\n" "$as_me: WARNING: no configuration information is in $ac_dir" >&2
     fi || ac_status=$?
     cd "$ac_pwd" || { ac_status=$?; break; }
   done
@@ -1622,10 +1663,10 @@
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-libpng configure 1.6.37
-generated by GNU Autoconf 2.69
+libpng configure 1.6.38
+generated by GNU Autoconf 2.71
 
-Copyright (C) 2012 Free Software Foundation, Inc.
+Copyright (C) 2021 Free Software Foundation, Inc.
 This configure script is free software; the Free Software Foundation
 gives unlimited permission to copy, distribute and modify it.
 _ACEOF
@@ -1642,14 +1683,14 @@
 ac_fn_c_try_compile ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  rm -f conftest.$ac_objext
+  rm -f conftest.$ac_objext conftest.beam
   if { { ac_try="$ac_compile"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compile") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1657,14 +1698,15 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       } && test -s conftest.$ac_objext; then :
+       } && test -s conftest.$ac_objext
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else $as_nop
+  printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
 	ac_retval=1
@@ -1686,7 +1728,7 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_cpp conftest.$ac_ext") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1694,14 +1736,15 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } > conftest.i && {
 	 test -z "$ac_c_preproc_warn_flag$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       }; then :
+       }
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else $as_nop
+  printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
     ac_retval=1
@@ -1717,14 +1760,14 @@
 ac_fn_c_try_link ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  rm -f conftest.$ac_objext conftest$ac_exeext
+  rm -f conftest.$ac_objext conftest.beam conftest$ac_exeext
   if { { ac_try="$ac_link"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1732,17 +1775,18 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
        } && test -s conftest$ac_exeext && {
 	 test "$cross_compiling" = yes ||
 	 test -x conftest$ac_exeext
-       }; then :
+       }
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else $as_nop
+  printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
 	ac_retval=1
@@ -1764,83 +1808,44 @@
 ac_fn_c_check_header_compile ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
+printf %s "checking for $2... " >&6; }
+if eval test \${$3+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 $4
 #include <$2>
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   eval "$3=yes"
-else
+else $as_nop
   eval "$3=no"
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 fi
 eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_check_header_compile
 
-# ac_fn_c_try_run LINENO
-# ----------------------
-# Try to link conftest.$ac_ext, and return whether this succeeded. Assumes
-# that executables *can* be run.
-ac_fn_c_try_run ()
-{
-  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  if { { ac_try="$ac_link"
-case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
-  (eval "$ac_link") 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; } && { ac_try='./conftest$ac_exeext'
-  { { case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
-  (eval "$ac_try") 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; }; then :
-  ac_retval=0
-else
-  $as_echo "$as_me: program exited with status $ac_status" >&5
-       $as_echo "$as_me: failed program was:" >&5
-sed 's/^/| /' conftest.$ac_ext >&5
-
-       ac_retval=$ac_status
-fi
-  rm -rf conftest.dSYM conftest_ipa8_conftest.oo
-  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
-  as_fn_set_status $ac_retval
-
-} # ac_fn_c_try_run
-
 # ac_fn_c_check_func LINENO FUNC VAR
 # ----------------------------------
 # Tests whether FUNC exists, setting the cache variable VAR accordingly
 ac_fn_c_check_func ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
+printf %s "checking for $2... " >&6; }
+if eval test \${$3+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 /* Define $2 to an innocuous variant, in case <limits.h> declares $2.
@@ -1848,16 +1853,9 @@
 #define $2 innocuous_$2
 
 /* System header to define __stub macros and hopefully few prototypes,
-    which can conflict with char $2 (); below.
-    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-    <limits.h> exists even on freestanding compilers.  */
+   which can conflict with char $2 (); below.  */
 
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
-
+#include <limits.h>
 #undef $2
 
 /* Override any GCC internal prototype to avoid an error.
@@ -1875,89 +1873,56 @@
 #endif
 
 int
-main ()
+main (void)
 {
 return $2 ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   eval "$3=yes"
-else
+else $as_nop
   eval "$3=no"
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 fi
 eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_check_func
+ac_configure_args_raw=
+for ac_arg
+do
+  case $ac_arg in
+  *\'*)
+    ac_arg=`printf "%s\n" "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
+  esac
+  as_fn_append ac_configure_args_raw " '$ac_arg'"
+done
 
-# ac_fn_c_check_type LINENO TYPE VAR INCLUDES
-# -------------------------------------------
-# Tests whether TYPE exists after having included INCLUDES, setting cache
-# variable VAR accordingly.
-ac_fn_c_check_type ()
-{
-  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  eval "$3=no"
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-$4
-int
-main ()
-{
-if (sizeof ($2))
-	 return 0;
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-$4
-int
-main ()
-{
-if (sizeof (($2)))
-	    return 0;
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+case $ac_configure_args_raw in
+  *$as_nl*)
+    ac_safe_unquote= ;;
+  *)
+    ac_unsafe_z='|&;<>()$`\\"*?[ ''	' # This string ends in space, tab.
+    ac_unsafe_a="$ac_unsafe_z#~"
+    ac_safe_unquote="s/ '\\([^$ac_unsafe_a][^$ac_unsafe_z]*\\)'/ \\1/g"
+    ac_configure_args_raw=`      printf "%s\n" "$ac_configure_args_raw" | sed "$ac_safe_unquote"`;;
+esac
 
-else
-  eval "$3=yes"
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
-
-} # ac_fn_c_check_type
 cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by libpng $as_me 1.6.37, which was
-generated by GNU Autoconf 2.69.  Invocation command line was
+It was created by libpng $as_me 1.6.38, which was
+generated by GNU Autoconf 2.71.  Invocation command line was
 
-  $ $0 $@
+  $ $0$ac_configure_args_raw
 
 _ACEOF
 exec 5>>config.log
@@ -1990,8 +1955,12 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    $as_echo "PATH: $as_dir"
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    printf "%s\n" "PATH: $as_dir"
   done
 IFS=$as_save_IFS
 
@@ -2026,7 +1995,7 @@
     | -silent | --silent | --silen | --sile | --sil)
       continue ;;
     *\'*)
-      ac_arg=`$as_echo "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
+      ac_arg=`printf "%s\n" "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
     esac
     case $ac_pass in
     1) as_fn_append ac_configure_args0 " '$ac_arg'" ;;
@@ -2061,11 +2030,13 @@
 # WARNING: Use '\'' to represent an apostrophe within the trap.
 # WARNING: Do not start the trap code with a newline, due to a FreeBSD 4.0 bug.
 trap 'exit_status=$?
+  # Sanitize IFS.
+  IFS=" ""	$as_nl"
   # Save into config.log some information that might help in debugging.
   {
     echo
 
-    $as_echo "## ---------------- ##
+    printf "%s\n" "## ---------------- ##
 ## Cache variables. ##
 ## ---------------- ##"
     echo
@@ -2076,8 +2047,8 @@
     case $ac_val in #(
     *${as_nl}*)
       case $ac_var in #(
-      *_cv_*) { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
-$as_echo "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
+      *_cv_*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
+printf "%s\n" "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
       esac
       case $ac_var in #(
       _ | IFS | as_nl) ;; #(
@@ -2101,7 +2072,7 @@
 )
     echo
 
-    $as_echo "## ----------------- ##
+    printf "%s\n" "## ----------------- ##
 ## Output variables. ##
 ## ----------------- ##"
     echo
@@ -2109,14 +2080,14 @@
     do
       eval ac_val=\$$ac_var
       case $ac_val in
-      *\'\''*) ac_val=`$as_echo "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
+      *\'\''*) ac_val=`printf "%s\n" "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
       esac
-      $as_echo "$ac_var='\''$ac_val'\''"
+      printf "%s\n" "$ac_var='\''$ac_val'\''"
     done | sort
     echo
 
     if test -n "$ac_subst_files"; then
-      $as_echo "## ------------------- ##
+      printf "%s\n" "## ------------------- ##
 ## File substitutions. ##
 ## ------------------- ##"
       echo
@@ -2124,15 +2095,15 @@
       do
 	eval ac_val=\$$ac_var
 	case $ac_val in
-	*\'\''*) ac_val=`$as_echo "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
+	*\'\''*) ac_val=`printf "%s\n" "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
 	esac
-	$as_echo "$ac_var='\''$ac_val'\''"
+	printf "%s\n" "$ac_var='\''$ac_val'\''"
       done | sort
       echo
     fi
 
     if test -s confdefs.h; then
-      $as_echo "## ----------- ##
+      printf "%s\n" "## ----------- ##
 ## confdefs.h. ##
 ## ----------- ##"
       echo
@@ -2140,8 +2111,8 @@
       echo
     fi
     test "$ac_signal" != 0 &&
-      $as_echo "$as_me: caught signal $ac_signal"
-    $as_echo "$as_me: exit $exit_status"
+      printf "%s\n" "$as_me: caught signal $ac_signal"
+    printf "%s\n" "$as_me: exit $exit_status"
   } >&5
   rm -f core *.core core.conftest.* &&
     rm -f -r conftest* confdefs* conf$$* $ac_clean_files &&
@@ -2155,63 +2126,48 @@
 # confdefs.h avoids OS command line length limits that DEFS can exceed.
 rm -f -r conftest* confdefs.h
 
-$as_echo "/* confdefs.h */" > confdefs.h
+printf "%s\n" "/* confdefs.h */" > confdefs.h
 
 # Predefined preprocessor variables.
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_NAME "$PACKAGE_NAME"
-_ACEOF
+printf "%s\n" "#define PACKAGE_NAME \"$PACKAGE_NAME\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_TARNAME "$PACKAGE_TARNAME"
-_ACEOF
+printf "%s\n" "#define PACKAGE_TARNAME \"$PACKAGE_TARNAME\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_VERSION "$PACKAGE_VERSION"
-_ACEOF
+printf "%s\n" "#define PACKAGE_VERSION \"$PACKAGE_VERSION\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_STRING "$PACKAGE_STRING"
-_ACEOF
+printf "%s\n" "#define PACKAGE_STRING \"$PACKAGE_STRING\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_BUGREPORT "$PACKAGE_BUGREPORT"
-_ACEOF
+printf "%s\n" "#define PACKAGE_BUGREPORT \"$PACKAGE_BUGREPORT\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_URL "$PACKAGE_URL"
-_ACEOF
+printf "%s\n" "#define PACKAGE_URL \"$PACKAGE_URL\"" >>confdefs.h
 
 
 # Let the site file select an alternate cache file if it wants to.
 # Prefer an explicitly selected file to automatically selected ones.
-ac_site_file1=NONE
-ac_site_file2=NONE
 if test -n "$CONFIG_SITE"; then
-  # We do not want a PATH search for config.site.
-  case $CONFIG_SITE in #((
-    -*)  ac_site_file1=./$CONFIG_SITE;;
-    */*) ac_site_file1=$CONFIG_SITE;;
-    *)   ac_site_file1=./$CONFIG_SITE;;
-  esac
+  ac_site_files="$CONFIG_SITE"
 elif test "x$prefix" != xNONE; then
-  ac_site_file1=$prefix/share/config.site
-  ac_site_file2=$prefix/etc/config.site
+  ac_site_files="$prefix/share/config.site $prefix/etc/config.site"
 else
-  ac_site_file1=$ac_default_prefix/share/config.site
-  ac_site_file2=$ac_default_prefix/etc/config.site
+  ac_site_files="$ac_default_prefix/share/config.site $ac_default_prefix/etc/config.site"
 fi
-for ac_site_file in "$ac_site_file1" "$ac_site_file2"
+
+for ac_site_file in $ac_site_files
 do
-  test "x$ac_site_file" = xNONE && continue
-  if test /dev/null != "$ac_site_file" && test -r "$ac_site_file"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: loading site script $ac_site_file" >&5
-$as_echo "$as_me: loading site script $ac_site_file" >&6;}
+  case $ac_site_file in #(
+  */*) :
+     ;; #(
+  *) :
+    ac_site_file=./$ac_site_file ;;
+esac
+  if test -f "$ac_site_file" && test -r "$ac_site_file"; then
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: loading site script $ac_site_file" >&5
+printf "%s\n" "$as_me: loading site script $ac_site_file" >&6;}
     sed 's/^/| /' "$ac_site_file" >&5
     . "$ac_site_file" \
-      || { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+      || { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "failed to load site script $ac_site_file
 See \`config.log' for more details" "$LINENO" 5; }
   fi
@@ -2221,19 +2177,434 @@
   # Some versions of bash will fail to source /dev/null (special files
   # actually), so we avoid doing that.  DJGPP emulates it as a regular file.
   if test /dev/null != "$cache_file" && test -f "$cache_file"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: loading cache $cache_file" >&5
-$as_echo "$as_me: loading cache $cache_file" >&6;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: loading cache $cache_file" >&5
+printf "%s\n" "$as_me: loading cache $cache_file" >&6;}
     case $cache_file in
       [\\/]* | ?:[\\/]* ) . "$cache_file";;
       *)                      . "./$cache_file";;
     esac
   fi
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: creating cache $cache_file" >&5
-$as_echo "$as_me: creating cache $cache_file" >&6;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating cache $cache_file" >&5
+printf "%s\n" "$as_me: creating cache $cache_file" >&6;}
   >$cache_file
 fi
 
+# Test code for whether the C compiler supports C89 (global declarations)
+ac_c_conftest_c89_globals='
+/* Does the compiler advertise C89 conformance?
+   Do not test the value of __STDC__, because some compilers set it to 0
+   while being otherwise adequately conformant. */
+#if !defined __STDC__
+# error "Compiler does not advertise C89 conformance"
+#endif
+
+#include <stddef.h>
+#include <stdarg.h>
+struct stat;
+/* Most of the following tests are stolen from RCS 5.7 src/conf.sh.  */
+struct buf { int x; };
+struct buf * (*rcsopen) (struct buf *, struct stat *, int);
+static char *e (p, i)
+     char **p;
+     int i;
+{
+  return p[i];
+}
+static char *f (char * (*g) (char **, int), char **p, ...)
+{
+  char *s;
+  va_list v;
+  va_start (v,p);
+  s = g (p, va_arg (v,int));
+  va_end (v);
+  return s;
+}
+
+/* OSF 4.0 Compaq cc is some sort of almost-ANSI by default.  It has
+   function prototypes and stuff, but not \xHH hex character constants.
+   These do not provoke an error unfortunately, instead are silently treated
+   as an "x".  The following induces an error, until -std is added to get
+   proper ANSI mode.  Curiously \x00 != x always comes out true, for an
+   array size at least.  It is necessary to write \x00 == 0 to get something
+   that is true only with -std.  */
+int osf4_cc_array ['\''\x00'\'' == 0 ? 1 : -1];
+
+/* IBM C 6 for AIX is almost-ANSI by default, but it replaces macro parameters
+   inside strings and character constants.  */
+#define FOO(x) '\''x'\''
+int xlc6_cc_array[FOO(a) == '\''x'\'' ? 1 : -1];
+
+int test (int i, double x);
+struct s1 {int (*f) (int a);};
+struct s2 {int (*f) (double a);};
+int pairnames (int, char **, int *(*)(struct buf *, struct stat *, int),
+               int, int);'
+
+# Test code for whether the C compiler supports C89 (body of main).
+ac_c_conftest_c89_main='
+ok |= (argc == 0 || f (e, argv, 0) != argv[0] || f (e, argv, 1) != argv[1]);
+'
+
+# Test code for whether the C compiler supports C99 (global declarations)
+ac_c_conftest_c99_globals='
+// Does the compiler advertise C99 conformance?
+#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 199901L
+# error "Compiler does not advertise C99 conformance"
+#endif
+
+#include <stdbool.h>
+extern int puts (const char *);
+extern int printf (const char *, ...);
+extern int dprintf (int, const char *, ...);
+extern void *malloc (size_t);
+
+// Check varargs macros.  These examples are taken from C99 6.10.3.5.
+// dprintf is used instead of fprintf to avoid needing to declare
+// FILE and stderr.
+#define debug(...) dprintf (2, __VA_ARGS__)
+#define showlist(...) puts (#__VA_ARGS__)
+#define report(test,...) ((test) ? puts (#test) : printf (__VA_ARGS__))
+static void
+test_varargs_macros (void)
+{
+  int x = 1234;
+  int y = 5678;
+  debug ("Flag");
+  debug ("X = %d\n", x);
+  showlist (The first, second, and third items.);
+  report (x>y, "x is %d but y is %d", x, y);
+}
+
+// Check long long types.
+#define BIG64 18446744073709551615ull
+#define BIG32 4294967295ul
+#define BIG_OK (BIG64 / BIG32 == 4294967297ull && BIG64 % BIG32 == 0)
+#if !BIG_OK
+  #error "your preprocessor is broken"
+#endif
+#if BIG_OK
+#else
+  #error "your preprocessor is broken"
+#endif
+static long long int bignum = -9223372036854775807LL;
+static unsigned long long int ubignum = BIG64;
+
+struct incomplete_array
+{
+  int datasize;
+  double data[];
+};
+
+struct named_init {
+  int number;
+  const wchar_t *name;
+  double average;
+};
+
+typedef const char *ccp;
+
+static inline int
+test_restrict (ccp restrict text)
+{
+  // See if C++-style comments work.
+  // Iterate through items via the restricted pointer.
+  // Also check for declarations in for loops.
+  for (unsigned int i = 0; *(text+i) != '\''\0'\''; ++i)
+    continue;
+  return 0;
+}
+
+// Check varargs and va_copy.
+static bool
+test_varargs (const char *format, ...)
+{
+  va_list args;
+  va_start (args, format);
+  va_list args_copy;
+  va_copy (args_copy, args);
+
+  const char *str = "";
+  int number = 0;
+  float fnumber = 0;
+
+  while (*format)
+    {
+      switch (*format++)
+	{
+	case '\''s'\'': // string
+	  str = va_arg (args_copy, const char *);
+	  break;
+	case '\''d'\'': // int
+	  number = va_arg (args_copy, int);
+	  break;
+	case '\''f'\'': // float
+	  fnumber = va_arg (args_copy, double);
+	  break;
+	default:
+	  break;
+	}
+    }
+  va_end (args_copy);
+  va_end (args);
+
+  return *str && number && fnumber;
+}
+'
+
+# Test code for whether the C compiler supports C99 (body of main).
+ac_c_conftest_c99_main='
+  // Check bool.
+  _Bool success = false;
+  success |= (argc != 0);
+
+  // Check restrict.
+  if (test_restrict ("String literal") == 0)
+    success = true;
+  char *restrict newvar = "Another string";
+
+  // Check varargs.
+  success &= test_varargs ("s, d'\'' f .", "string", 65, 34.234);
+  test_varargs_macros ();
+
+  // Check flexible array members.
+  struct incomplete_array *ia =
+    malloc (sizeof (struct incomplete_array) + (sizeof (double) * 10));
+  ia->datasize = 10;
+  for (int i = 0; i < ia->datasize; ++i)
+    ia->data[i] = i * 1.234;
+
+  // Check named initializers.
+  struct named_init ni = {
+    .number = 34,
+    .name = L"Test wide string",
+    .average = 543.34343,
+  };
+
+  ni.number = 58;
+
+  int dynamic_array[ni.number];
+  dynamic_array[0] = argv[0][0];
+  dynamic_array[ni.number - 1] = 543;
+
+  // work around unused variable warnings
+  ok |= (!success || bignum == 0LL || ubignum == 0uLL || newvar[0] == '\''x'\''
+	 || dynamic_array[ni.number - 1] != 543);
+'
+
+# Test code for whether the C compiler supports C11 (global declarations)
+ac_c_conftest_c11_globals='
+// Does the compiler advertise C11 conformance?
+#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112L
+# error "Compiler does not advertise C11 conformance"
+#endif
+
+// Check _Alignas.
+char _Alignas (double) aligned_as_double;
+char _Alignas (0) no_special_alignment;
+extern char aligned_as_int;
+char _Alignas (0) _Alignas (int) aligned_as_int;
+
+// Check _Alignof.
+enum
+{
+  int_alignment = _Alignof (int),
+  int_array_alignment = _Alignof (int[100]),
+  char_alignment = _Alignof (char)
+};
+_Static_assert (0 < -_Alignof (int), "_Alignof is signed");
+
+// Check _Noreturn.
+int _Noreturn does_not_return (void) { for (;;) continue; }
+
+// Check _Static_assert.
+struct test_static_assert
+{
+  int x;
+  _Static_assert (sizeof (int) <= sizeof (long int),
+                  "_Static_assert does not work in struct");
+  long int y;
+};
+
+// Check UTF-8 literals.
+#define u8 syntax error!
+char const utf8_literal[] = u8"happens to be ASCII" "another string";
+
+// Check duplicate typedefs.
+typedef long *long_ptr;
+typedef long int *long_ptr;
+typedef long_ptr long_ptr;
+
+// Anonymous structures and unions -- taken from C11 6.7.2.1 Example 1.
+struct anonymous
+{
+  union {
+    struct { int i; int j; };
+    struct { int k; long int l; } w;
+  };
+  int m;
+} v1;
+'
+
+# Test code for whether the C compiler supports C11 (body of main).
+ac_c_conftest_c11_main='
+  _Static_assert ((offsetof (struct anonymous, i)
+		   == offsetof (struct anonymous, w.k)),
+		  "Anonymous union alignment botch");
+  v1.i = 2;
+  v1.w.k = 5;
+  ok |= v1.i != 5;
+'
+
+# Test code for whether the C compiler supports C11 (complete).
+ac_c_conftest_c11_program="${ac_c_conftest_c89_globals}
+${ac_c_conftest_c99_globals}
+${ac_c_conftest_c11_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  ${ac_c_conftest_c99_main}
+  ${ac_c_conftest_c11_main}
+  return ok;
+}
+"
+
+# Test code for whether the C compiler supports C99 (complete).
+ac_c_conftest_c99_program="${ac_c_conftest_c89_globals}
+${ac_c_conftest_c99_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  ${ac_c_conftest_c99_main}
+  return ok;
+}
+"
+
+# Test code for whether the C compiler supports C89 (complete).
+ac_c_conftest_c89_program="${ac_c_conftest_c89_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  return ok;
+}
+"
+
+as_fn_append ac_header_c_list " stdio.h stdio_h HAVE_STDIO_H"
+as_fn_append ac_header_c_list " stdlib.h stdlib_h HAVE_STDLIB_H"
+as_fn_append ac_header_c_list " string.h string_h HAVE_STRING_H"
+as_fn_append ac_header_c_list " inttypes.h inttypes_h HAVE_INTTYPES_H"
+as_fn_append ac_header_c_list " stdint.h stdint_h HAVE_STDINT_H"
+as_fn_append ac_header_c_list " strings.h strings_h HAVE_STRINGS_H"
+as_fn_append ac_header_c_list " sys/stat.h sys_stat_h HAVE_SYS_STAT_H"
+as_fn_append ac_header_c_list " sys/types.h sys_types_h HAVE_SYS_TYPES_H"
+as_fn_append ac_header_c_list " unistd.h unistd_h HAVE_UNISTD_H"
+
+# Auxiliary files required by this configure script.
+ac_aux_files="ltmain.sh config.guess config.sub compile missing install-sh"
+
+# Locations in which to look for auxiliary files.
+ac_aux_dir_candidates="${srcdir}${PATH_SEPARATOR}${srcdir}/..${PATH_SEPARATOR}${srcdir}/../.."
+
+# Search for a directory containing all of the required auxiliary files,
+# $ac_aux_files, from the $PATH-style list $ac_aux_dir_candidates.
+# If we don't find one directory that contains all the files we need,
+# we report the set of missing files from the *first* directory in
+# $ac_aux_dir_candidates and give up.
+ac_missing_aux_files=""
+ac_first_candidate=:
+printf "%s\n" "$as_me:${as_lineno-$LINENO}: looking for aux files: $ac_aux_files" >&5
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+as_found=false
+for as_dir in $ac_aux_dir_candidates
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+  as_found=:
+
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}:  trying $as_dir" >&5
+  ac_aux_dir_found=yes
+  ac_install_sh=
+  for ac_aux in $ac_aux_files
+  do
+    # As a special case, if "install-sh" is required, that requirement
+    # can be satisfied by any of "install-sh", "install.sh", or "shtool",
+    # and $ac_install_sh is set appropriately for whichever one is found.
+    if test x"$ac_aux" = x"install-sh"
+    then
+      if test -f "${as_dir}install-sh"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}install-sh found" >&5
+        ac_install_sh="${as_dir}install-sh -c"
+      elif test -f "${as_dir}install.sh"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}install.sh found" >&5
+        ac_install_sh="${as_dir}install.sh -c"
+      elif test -f "${as_dir}shtool"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}shtool found" >&5
+        ac_install_sh="${as_dir}shtool install -c"
+      else
+        ac_aux_dir_found=no
+        if $ac_first_candidate; then
+          ac_missing_aux_files="${ac_missing_aux_files} install-sh"
+        else
+          break
+        fi
+      fi
+    else
+      if test -f "${as_dir}${ac_aux}"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}${ac_aux} found" >&5
+      else
+        ac_aux_dir_found=no
+        if $ac_first_candidate; then
+          ac_missing_aux_files="${ac_missing_aux_files} ${ac_aux}"
+        else
+          break
+        fi
+      fi
+    fi
+  done
+  if test "$ac_aux_dir_found" = yes; then
+    ac_aux_dir="$as_dir"
+    break
+  fi
+  ac_first_candidate=false
+
+  as_found=false
+done
+IFS=$as_save_IFS
+if $as_found
+then :
+
+else $as_nop
+  as_fn_error $? "cannot find required auxiliary files:$ac_missing_aux_files" "$LINENO" 5
+fi
+
+
+# These three variables are undocumented and unsupported,
+# and are intended to be withdrawn in a future Autoconf release.
+# They can cause serious problems if a builder's source tree is in a directory
+# whose full name contains unusual characters.
+if test -f "${ac_aux_dir}config.guess"; then
+  ac_config_guess="$SHELL ${ac_aux_dir}config.guess"
+fi
+if test -f "${ac_aux_dir}config.sub"; then
+  ac_config_sub="$SHELL ${ac_aux_dir}config.sub"
+fi
+if test -f "$ac_aux_dir/configure"; then
+  ac_configure="$SHELL ${ac_aux_dir}configure"
+fi
+
 # Check that the precious variables saved in the cache have kept the same
 # value.
 ac_cache_corrupted=false
@@ -2244,12 +2615,12 @@
   eval ac_new_val=\$ac_env_${ac_var}_value
   case $ac_old_set,$ac_new_set in
     set,)
-      { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&5
-$as_echo "$as_me: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&2;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&5
+printf "%s\n" "$as_me: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&2;}
       ac_cache_corrupted=: ;;
     ,set)
-      { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was not set in the previous run" >&5
-$as_echo "$as_me: error: \`$ac_var' was not set in the previous run" >&2;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was not set in the previous run" >&5
+printf "%s\n" "$as_me: error: \`$ac_var' was not set in the previous run" >&2;}
       ac_cache_corrupted=: ;;
     ,);;
     *)
@@ -2258,24 +2629,24 @@
 	ac_old_val_w=`echo x $ac_old_val`
 	ac_new_val_w=`echo x $ac_new_val`
 	if test "$ac_old_val_w" != "$ac_new_val_w"; then
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' has changed since the previous run:" >&5
-$as_echo "$as_me: error: \`$ac_var' has changed since the previous run:" >&2;}
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' has changed since the previous run:" >&5
+printf "%s\n" "$as_me: error: \`$ac_var' has changed since the previous run:" >&2;}
 	  ac_cache_corrupted=:
 	else
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&5
-$as_echo "$as_me: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&2;}
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&5
+printf "%s\n" "$as_me: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&2;}
 	  eval $ac_var=\$ac_old_val
 	fi
-	{ $as_echo "$as_me:${as_lineno-$LINENO}:   former value:  \`$ac_old_val'" >&5
-$as_echo "$as_me:   former value:  \`$ac_old_val'" >&2;}
-	{ $as_echo "$as_me:${as_lineno-$LINENO}:   current value: \`$ac_new_val'" >&5
-$as_echo "$as_me:   current value: \`$ac_new_val'" >&2;}
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}:   former value:  \`$ac_old_val'" >&5
+printf "%s\n" "$as_me:   former value:  \`$ac_old_val'" >&2;}
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}:   current value: \`$ac_new_val'" >&5
+printf "%s\n" "$as_me:   current value: \`$ac_new_val'" >&2;}
       fi;;
   esac
   # Pass precious variables to config.status.
   if test "$ac_new_set" = set; then
     case $ac_new_val in
-    *\'*) ac_arg=$ac_var=`$as_echo "$ac_new_val" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_arg=$ac_var=`printf "%s\n" "$ac_new_val" | sed "s/'/'\\\\\\\\''/g"` ;;
     *) ac_arg=$ac_var=$ac_new_val ;;
     esac
     case " $ac_configure_args " in
@@ -2285,11 +2656,12 @@
   fi
 done
 if $ac_cache_corrupted; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
-  { $as_echo "$as_me:${as_lineno-$LINENO}: error: changes in the environment can compromise the build" >&5
-$as_echo "$as_me: error: changes in the environment can compromise the build" >&2;}
-  as_fn_error $? "run \`make distclean' and/or \`rm $cache_file' and start over" "$LINENO" 5
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: changes in the environment can compromise the build" >&5
+printf "%s\n" "$as_me: error: changes in the environment can compromise the build" >&2;}
+  as_fn_error $? "run \`${MAKE-make} distclean' and/or \`rm $cache_file'
+	    and start over" "$LINENO" 5
 fi
 ## -------------------- ##
 ## Main body of script. ##
@@ -2312,36 +2684,9 @@
 # 1.13 is required for parallel tests
 am__api_version='1.16'
 
-ac_aux_dir=
-for ac_dir in "$srcdir" "$srcdir/.." "$srcdir/../.."; do
-  if test -f "$ac_dir/install-sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install-sh -c"
-    break
-  elif test -f "$ac_dir/install.sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install.sh -c"
-    break
-  elif test -f "$ac_dir/shtool"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/shtool install -c"
-    break
-  fi
-done
-if test -z "$ac_aux_dir"; then
-  as_fn_error $? "cannot find install-sh, install.sh, or shtool in \"$srcdir\" \"$srcdir/..\" \"$srcdir/../..\"" "$LINENO" 5
-fi
-
-# These three variables are undocumented and unsupported,
-# and are intended to be withdrawn in a future Autoconf release.
-# They can cause serious problems if a builder's source tree is in a directory
-# whose full name contains unusual characters.
-ac_config_guess="$SHELL $ac_aux_dir/config.guess"  # Please don't use this var.
-ac_config_sub="$SHELL $ac_aux_dir/config.sub"  # Please don't use this var.
-ac_configure="$SHELL $ac_aux_dir/configure"  # Please don't use this var.
 
 
-# Find a good install program.  We prefer a C program (faster),
+  # Find a good install program.  We prefer a C program (faster),
 # so one script is as good as another.  But avoid the broken or
 # incompatible versions:
 # SysV /etc/install, /usr/sbin/install
@@ -2355,20 +2700,25 @@
 # OS/2's system install, which has a completely different semantic
 # ./install, which can be erroneously created by make from ./install.sh.
 # Reject install programs that cannot install multiple files.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a BSD-compatible install" >&5
-$as_echo_n "checking for a BSD-compatible install... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a BSD-compatible install" >&5
+printf %s "checking for a BSD-compatible install... " >&6; }
 if test -z "$INSTALL"; then
-if ${ac_cv_path_install+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+if test ${ac_cv_path_install+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    # Account for people who put trailing slashes in PATH elements.
-case $as_dir/ in #((
-  ./ | .// | /[cC]/* | \
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    # Account for fact that we put trailing slashes in our PATH walk.
+case $as_dir in #((
+  ./ | /[cC]/* | \
   /etc/* | /usr/sbin/* | /usr/etc/* | /sbin/* | /usr/afsws/bin/* | \
   ?:[\\/]os2[\\/]install[\\/]* | ?:[\\/]OS2[\\/]INSTALL[\\/]* | \
   /usr/ucb/* ) ;;
@@ -2378,13 +2728,13 @@
     # by default.
     for ac_prog in ginstall scoinst install; do
       for ac_exec_ext in '' $ac_executable_extensions; do
-	if as_fn_executable_p "$as_dir/$ac_prog$ac_exec_ext"; then
+	if as_fn_executable_p "$as_dir$ac_prog$ac_exec_ext"; then
 	  if test $ac_prog = install &&
-	    grep dspmsg "$as_dir/$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
+	    grep dspmsg "$as_dir$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
 	    # AIX install.  It has an incompatible calling convention.
 	    :
 	  elif test $ac_prog = install &&
-	    grep pwplus "$as_dir/$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
+	    grep pwplus "$as_dir$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
 	    # program-specific install script used by HP pwplus--don't use.
 	    :
 	  else
@@ -2392,12 +2742,12 @@
 	    echo one > conftest.one
 	    echo two > conftest.two
 	    mkdir conftest.dir
-	    if "$as_dir/$ac_prog$ac_exec_ext" -c conftest.one conftest.two "`pwd`/conftest.dir" &&
+	    if "$as_dir$ac_prog$ac_exec_ext" -c conftest.one conftest.two "`pwd`/conftest.dir/" &&
 	      test -s conftest.one && test -s conftest.two &&
 	      test -s conftest.dir/conftest.one &&
 	      test -s conftest.dir/conftest.two
 	    then
-	      ac_cv_path_install="$as_dir/$ac_prog$ac_exec_ext -c"
+	      ac_cv_path_install="$as_dir$ac_prog$ac_exec_ext -c"
 	      break 3
 	    fi
 	  fi
@@ -2413,7 +2763,7 @@
 rm -rf conftest.one conftest.two conftest.dir
 
 fi
-  if test "${ac_cv_path_install+set}" = set; then
+  if test ${ac_cv_path_install+y}; then
     INSTALL=$ac_cv_path_install
   else
     # As a last resort, use the slow shell script.  Don't cache a
@@ -2423,8 +2773,8 @@
     INSTALL=$ac_install_sh
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $INSTALL" >&5
-$as_echo "$INSTALL" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $INSTALL" >&5
+printf "%s\n" "$INSTALL" >&6; }
 
 # Use test -z because SunOS4 sh mishandles braces in ${var-val}.
 # It thinks the first close brace ends the variable substitution.
@@ -2434,8 +2784,8 @@
 
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether build environment is sane" >&5
-$as_echo_n "checking whether build environment is sane... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether build environment is sane" >&5
+printf %s "checking whether build environment is sane... " >&6; }
 # Reject unsafe characters in $srcdir or the absolute working directory
 # name.  Accept space and tab only in the latter.
 am_lf='
@@ -2489,8 +2839,8 @@
    as_fn_error $? "newly created file is older than distributed files!
 Check your system clock" "$LINENO" 5
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 # If we didn't sleep, we still need to ensure time stamps of config.status and
 # generated files are strictly newer.
 am_sleep_pid=
@@ -2509,26 +2859,23 @@
 # Double any \ or $.
 # By default was `s,x,x', remove it if useless.
 ac_script='s/[\\$]/&&/g;s/;s,x,x,$//'
-program_transform_name=`$as_echo "$program_transform_name" | sed "$ac_script"`
+program_transform_name=`printf "%s\n" "$program_transform_name" | sed "$ac_script"`
+
 
 # Expand $ac_aux_dir to an absolute path.
 am_aux_dir=`cd "$ac_aux_dir" && pwd`
 
-if test x"${MISSING+set}" != xset; then
-  case $am_aux_dir in
-  *\ * | *\	*)
-    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
-  *)
-    MISSING="\${SHELL} $am_aux_dir/missing" ;;
-  esac
+
+  if test x"${MISSING+set}" != xset; then
+  MISSING="\${SHELL} '$am_aux_dir/missing'"
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
   am_missing_run="$MISSING "
 else
   am_missing_run=
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: 'missing' script is too old or missing" >&5
-$as_echo "$as_me: WARNING: 'missing' script is too old or missing" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: 'missing' script is too old or missing" >&5
+printf "%s\n" "$as_me: WARNING: 'missing' script is too old or missing" >&2;}
 fi
 
 if test x"${install_sh+set}" != xset; then
@@ -2548,11 +2895,12 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}strip", so it can be a program name with args.
 set dummy ${ac_tool_prefix}strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$STRIP"; then
   ac_cv_prog_STRIP="$STRIP" # Let the user override the test.
 else
@@ -2560,11 +2908,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_STRIP="${ac_tool_prefix}strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -2575,11 +2927,11 @@
 fi
 STRIP=$ac_cv_prog_STRIP
 if test -n "$STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
-$as_echo "$STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
+printf "%s\n" "$STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -2588,11 +2940,12 @@
   ac_ct_STRIP=$STRIP
   # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_STRIP"; then
   ac_cv_prog_ac_ct_STRIP="$ac_ct_STRIP" # Let the user override the test.
 else
@@ -2600,11 +2953,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_STRIP="strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -2615,11 +2972,11 @@
 fi
 ac_ct_STRIP=$ac_cv_prog_ac_ct_STRIP
 if test -n "$ac_ct_STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
-$as_echo "$ac_ct_STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
+printf "%s\n" "$ac_ct_STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_STRIP" = x; then
@@ -2627,8 +2984,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     STRIP=$ac_ct_STRIP
@@ -2640,25 +2997,31 @@
 fi
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a thread-safe mkdir -p" >&5
-$as_echo_n "checking for a thread-safe mkdir -p... " >&6; }
+
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a race-free mkdir -p" >&5
+printf %s "checking for a race-free mkdir -p... " >&6; }
 if test -z "$MKDIR_P"; then
-  if ${ac_cv_path_mkdir+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  if test ${ac_cv_path_mkdir+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH$PATH_SEPARATOR/opt/sfw/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_prog in mkdir gmkdir; do
 	 for ac_exec_ext in '' $ac_executable_extensions; do
-	   as_fn_executable_p "$as_dir/$ac_prog$ac_exec_ext" || continue
-	   case `"$as_dir/$ac_prog$ac_exec_ext" --version 2>&1` in #(
-	     'mkdir (GNU coreutils) '* | \
-	     'mkdir (coreutils) '* | \
+	   as_fn_executable_p "$as_dir$ac_prog$ac_exec_ext" || continue
+	   case `"$as_dir$ac_prog$ac_exec_ext" --version 2>&1` in #(
+	     'mkdir ('*'coreutils) '* | \
+	     'BusyBox '* | \
 	     'mkdir (fileutils) '4.1*)
-	       ac_cv_path_mkdir=$as_dir/$ac_prog$ac_exec_ext
+	       ac_cv_path_mkdir=$as_dir$ac_prog$ac_exec_ext
 	       break 3;;
 	   esac
 	 done
@@ -2669,7 +3032,7 @@
 fi
 
   test -d ./--version && rmdir ./--version
-  if test "${ac_cv_path_mkdir+set}" = set; then
+  if test ${ac_cv_path_mkdir+y}; then
     MKDIR_P="$ac_cv_path_mkdir -p"
   else
     # As a last resort, use the slow shell script.  Don't cache a
@@ -2679,18 +3042,19 @@
     MKDIR_P="$ac_install_sh -d"
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $MKDIR_P" >&5
-$as_echo "$MKDIR_P" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MKDIR_P" >&5
+printf "%s\n" "$MKDIR_P" >&6; }
 
 for ac_prog in gawk mawk nawk awk
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AWK+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AWK+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$AWK"; then
   ac_cv_prog_AWK="$AWK" # Let the user override the test.
 else
@@ -2698,11 +3062,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AWK="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -2713,24 +3081,25 @@
 fi
 AWK=$ac_cv_prog_AWK
 if test -n "$AWK"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
-$as_echo "$AWK" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
+printf "%s\n" "$AWK" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
   test -n "$AWK" && break
 done
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
-$as_echo_n "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
+printf %s "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
 set x ${MAKE-make}
-ac_make=`$as_echo "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
-if eval \${ac_cv_prog_make_${ac_make}_set+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+ac_make=`printf "%s\n" "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
+if eval test \${ac_cv_prog_make_${ac_make}_set+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat >conftest.make <<\_ACEOF
 SHELL = /bin/sh
 all:
@@ -2746,12 +3115,12 @@
 rm -f conftest.make
 fi
 if eval test \$ac_cv_prog_make_${ac_make}_set = yes; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
   SET_MAKE=
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
   SET_MAKE="MAKE=${MAKE-make}"
 fi
 
@@ -2765,7 +3134,8 @@
 rmdir .tst 2>/dev/null
 
 # Check whether --enable-silent-rules was given.
-if test "${enable_silent_rules+set}" = set; then :
+if test ${enable_silent_rules+y}
+then :
   enableval=$enable_silent_rules;
 fi
 
@@ -2775,12 +3145,13 @@
     *) AM_DEFAULT_VERBOSITY=1;;
 esac
 am_make=${MAKE-make}
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $am_make supports nested variables" >&5
-$as_echo_n "checking whether $am_make supports nested variables... " >&6; }
-if ${am_cv_make_support_nested_variables+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if $as_echo 'TRUE=$(BAR$(V))
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $am_make supports nested variables" >&5
+printf %s "checking whether $am_make supports nested variables... " >&6; }
+if test ${am_cv_make_support_nested_variables+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  if printf "%s\n" 'TRUE=$(BAR$(V))
 BAR0=false
 BAR1=true
 V=1
@@ -2792,8 +3163,8 @@
   am_cv_make_support_nested_variables=no
 fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_make_support_nested_variables" >&5
-$as_echo "$am_cv_make_support_nested_variables" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_make_support_nested_variables" >&5
+printf "%s\n" "$am_cv_make_support_nested_variables" >&6; }
 if test $am_cv_make_support_nested_variables = yes; then
     AM_V='$(V)'
   AM_DEFAULT_V='$(AM_DEFAULT_VERBOSITY)'
@@ -2825,17 +3196,13 @@
 
 # Define the identity of the package.
  PACKAGE='libpng'
- VERSION='1.6.37'
+ VERSION='1.6.38'
 
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE "$PACKAGE"
-_ACEOF
+printf "%s\n" "#define PACKAGE \"$PACKAGE\"" >>confdefs.h
 
 
-cat >>confdefs.h <<_ACEOF
-#define VERSION "$VERSION"
-_ACEOF
+printf "%s\n" "#define VERSION \"$VERSION\"" >>confdefs.h
 
 # Some tools Automake needs.
 
@@ -2875,6 +3242,20 @@
 
 
 
+# Variables for tags utilities; see am/tags.am
+if test -z "$CTAGS"; then
+  CTAGS=ctags
+fi
+
+if test -z "$ETAGS"; then
+  ETAGS=etags
+fi
+
+if test -z "$CSCOPE"; then
+  CSCOPE=cscope
+fi
+
+
 
 # POSIX will say in a future version that running "rm -f" with no argument
 # is OK; and we want to be able to make that assumption in our Makefile
@@ -2922,17 +3303,18 @@
 # configure. This is necessary because libpng distributions cannot rely on the
 # time stamps of the autotools generated files being correct
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to enable maintainer-specific portions of Makefiles" >&5
-$as_echo_n "checking whether to enable maintainer-specific portions of Makefiles... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to enable maintainer-specific portions of Makefiles" >&5
+printf %s "checking whether to enable maintainer-specific portions of Makefiles... " >&6; }
     # Check whether --enable-maintainer-mode was given.
-if test "${enable_maintainer_mode+set}" = set; then :
+if test ${enable_maintainer_mode+y}
+then :
   enableval=$enable_maintainer_mode; USE_MAINTAINER_MODE=$enableval
-else
+else $as_nop
   USE_MAINTAINER_MODE=no
 fi
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $USE_MAINTAINER_MODE" >&5
-$as_echo "$USE_MAINTAINER_MODE" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $USE_MAINTAINER_MODE" >&5
+printf "%s\n" "$USE_MAINTAINER_MODE" >&6; }
    if test $USE_MAINTAINER_MODE = yes; then
   MAINTAINER_MODE_TRUE=
   MAINTAINER_MODE_FALSE='#'
@@ -2946,10 +3328,10 @@
 
 
 
-PNGLIB_VERSION=1.6.37
+PNGLIB_VERSION=1.6.38
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=37
+PNGLIB_RELEASE=38
 
 
 
@@ -2963,6 +3345,15 @@
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
+
+
+
+
+
+
+
+
+
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
@@ -2971,11 +3362,12 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}gcc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}gcc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
@@ -2983,11 +3375,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="${ac_tool_prefix}gcc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -2998,11 +3394,11 @@
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3011,11 +3407,12 @@
   ac_ct_CC=$CC
   # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_CC"; then
   ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
 else
@@ -3023,11 +3420,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_CC="gcc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3038,11 +3439,11 @@
 fi
 ac_ct_CC=$ac_cv_prog_ac_ct_CC
 if test -n "$ac_ct_CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
-$as_echo "$ac_ct_CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_CC" = x; then
@@ -3050,8 +3451,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     CC=$ac_ct_CC
@@ -3064,11 +3465,12 @@
           if test -n "$ac_tool_prefix"; then
     # Extract the first word of "${ac_tool_prefix}cc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}cc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
@@ -3076,11 +3478,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="${ac_tool_prefix}cc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3091,11 +3497,11 @@
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3104,11 +3510,12 @@
 if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
@@ -3117,15 +3524,19 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    if test "$as_dir/$ac_word$ac_exec_ext" = "/usr/ucb/cc"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    if test "$as_dir$ac_word$ac_exec_ext" = "/usr/ucb/cc"; then
        ac_prog_rejected=yes
        continue
      fi
     ac_cv_prog_CC="cc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3141,18 +3552,18 @@
     # However, it has the same basename, so the bogon will be chosen
     # first if we set CC to just the basename; use the full file name.
     shift
-    ac_cv_prog_CC="$as_dir/$ac_word${1+' '}$@"
+    ac_cv_prog_CC="$as_dir$ac_word${1+' '}$@"
   fi
 fi
 fi
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3163,11 +3574,12 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
@@ -3175,11 +3587,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3190,11 +3606,11 @@
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3207,11 +3623,12 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_CC"; then
   ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
 else
@@ -3219,11 +3636,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_CC="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3234,11 +3655,11 @@
 fi
 ac_ct_CC=$ac_cv_prog_ac_ct_CC
 if test -n "$ac_ct_CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
-$as_echo "$ac_ct_CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3250,8 +3671,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     CC=$ac_ct_CC
@@ -3259,25 +3680,129 @@
 fi
 
 fi
+if test -z "$CC"; then
+  if test -n "$ac_tool_prefix"; then
+  # Extract the first word of "${ac_tool_prefix}clang", so it can be a program name with args.
+set dummy ${ac_tool_prefix}clang; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  if test -n "$CC"; then
+  ac_cv_prog_CC="$CC" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_CC="${ac_tool_prefix}clang"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+CC=$ac_cv_prog_CC
+if test -n "$CC"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
 
 
-test -z "$CC" && { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+fi
+if test -z "$ac_cv_prog_CC"; then
+  ac_ct_CC=$CC
+  # Extract the first word of "clang", so it can be a program name with args.
+set dummy clang; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  if test -n "$ac_ct_CC"; then
+  ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_ac_ct_CC="clang"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+ac_ct_CC=$ac_cv_prog_ac_ct_CC
+if test -n "$ac_ct_CC"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+  if test "x$ac_ct_CC" = x; then
+    CC=""
+  else
+    case $cross_compiling:$ac_tool_warned in
+yes:)
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+ac_tool_warned=yes ;;
+esac
+    CC=$ac_ct_CC
+  fi
+else
+  CC="$ac_cv_prog_CC"
+fi
+
+fi
+
+
+test -z "$CC" && { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "no acceptable C compiler found in \$PATH
 See \`config.log' for more details" "$LINENO" 5; }
 
 # Provide some information about the compiler.
-$as_echo "$as_me:${as_lineno-$LINENO}: checking for C compiler version" >&5
+printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C compiler version" >&5
 set X $ac_compile
 ac_compiler=$2
-for ac_option in --version -v -V -qversion; do
+for ac_option in --version -v -V -qversion -version; do
   { { ac_try="$ac_compiler $ac_option >&5"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compiler $ac_option >&5") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -3287,7 +3812,7 @@
     cat conftest.er1 >&5
   fi
   rm -f conftest.er1 conftest.err
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 done
 
@@ -3295,7 +3820,7 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3307,9 +3832,9 @@
 # Try to create an executable without -o first, disregard a.out.
 # It will help us diagnose broken compilers, and finding out an intuition
 # of exeext.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the C compiler works" >&5
-$as_echo_n "checking whether the C compiler works... " >&6; }
-ac_link_default=`$as_echo "$ac_link" | sed 's/ -o *conftest[^ ]*//'`
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the C compiler works" >&5
+printf %s "checking whether the C compiler works... " >&6; }
+ac_link_default=`printf "%s\n" "$ac_link" | sed 's/ -o *conftest[^ ]*//'`
 
 # The possible output files:
 ac_files="a.out conftest.exe conftest a.exe a_out.exe b.out conftest.*"
@@ -3330,11 +3855,12 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link_default") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
   # Autoconf-2.13 could set the ac_cv_exeext variable to `no'.
 # So ignore a value of `no', otherwise this would lead to `EXEEXT = no'
 # in a Makefile.  We should not override ac_cv_exeext if it was cached,
@@ -3351,7 +3877,7 @@
 	# certainly right.
 	break;;
     *.* )
-	if test "${ac_cv_exeext+set}" = set && test "$ac_cv_exeext" != no;
+	if test ${ac_cv_exeext+y} && test "$ac_cv_exeext" != no;
 	then :; else
 	   ac_cv_exeext=`expr "$ac_file" : '[^.]*\(\..*\)'`
 	fi
@@ -3367,44 +3893,46 @@
 done
 test "$ac_cv_exeext" = no && ac_cv_exeext=
 
-else
+else $as_nop
   ac_file=''
 fi
-if test -z "$ac_file"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-$as_echo "$as_me: failed program was:" >&5
+if test -z "$ac_file"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error 77 "C compiler cannot create executables
 See \`config.log' for more details" "$LINENO" 5; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for C compiler default output file name" >&5
-$as_echo_n "checking for C compiler default output file name... " >&6; }
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_file" >&5
-$as_echo "$ac_file" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C compiler default output file name" >&5
+printf %s "checking for C compiler default output file name... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_file" >&5
+printf "%s\n" "$ac_file" >&6; }
 ac_exeext=$ac_cv_exeext
 
 rm -f -r a.out a.out.dSYM a.exe conftest$ac_cv_exeext b.out
 ac_clean_files=$ac_clean_files_save
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for suffix of executables" >&5
-$as_echo_n "checking for suffix of executables... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for suffix of executables" >&5
+printf %s "checking for suffix of executables... " >&6; }
 if { { ac_try="$ac_link"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
   # If both `conftest.exe' and `conftest' are `present' (well, observable)
 # catch `conftest.exe'.  For instance with Cygwin, `ls conftest' will
 # work properly (i.e., refer to `conftest.exe'), while it won't with
@@ -3418,15 +3946,15 @@
     * ) break;;
   esac
 done
-else
-  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+else $as_nop
+  { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "cannot compute suffix of executables: cannot compile and link
 See \`config.log' for more details" "$LINENO" 5; }
 fi
 rm -f conftest conftest$ac_cv_exeext
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_exeext" >&5
-$as_echo "$ac_cv_exeext" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_exeext" >&5
+printf "%s\n" "$ac_cv_exeext" >&6; }
 
 rm -f conftest.$ac_ext
 EXEEXT=$ac_cv_exeext
@@ -3435,7 +3963,7 @@
 /* end confdefs.h.  */
 #include <stdio.h>
 int
-main ()
+main (void)
 {
 FILE *f = fopen ("conftest.out", "w");
  return ferror (f) || fclose (f) != 0;
@@ -3447,8 +3975,8 @@
 ac_clean_files="$ac_clean_files conftest.out"
 # Check that the compiler produces executables we can run.  If not, either
 # the compiler is broken, or we cross compile.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether we are cross compiling" >&5
-$as_echo_n "checking whether we are cross compiling... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether we are cross compiling" >&5
+printf %s "checking whether we are cross compiling... " >&6; }
 if test "$cross_compiling" != yes; then
   { { ac_try="$ac_link"
 case "(($ac_try" in
@@ -3456,10 +3984,10 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
   if { ac_try='./conftest$ac_cv_exeext'
   { { case "(($ac_try" in
@@ -3467,39 +3995,40 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_try") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; }; then
     cross_compiling=no
   else
     if test "$cross_compiling" = maybe; then
 	cross_compiling=yes
     else
-	{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
-as_fn_error $? "cannot run C compiled programs.
+	{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error 77 "cannot run C compiled programs.
 If you meant to cross compile, use \`--host'.
 See \`config.log' for more details" "$LINENO" 5; }
     fi
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $cross_compiling" >&5
-$as_echo "$cross_compiling" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $cross_compiling" >&5
+printf "%s\n" "$cross_compiling" >&6; }
 
 rm -f conftest.$ac_ext conftest$ac_cv_exeext conftest.out
 ac_clean_files=$ac_clean_files_save
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for suffix of object files" >&5
-$as_echo_n "checking for suffix of object files... " >&6; }
-if ${ac_cv_objext+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for suffix of object files" >&5
+printf %s "checking for suffix of object files... " >&6; }
+if test ${ac_cv_objext+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3513,11 +4042,12 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compile") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
   for ac_file in conftest.o conftest.obj conftest.*; do
   test -f "$ac_file" || continue;
   case $ac_file in
@@ -3526,31 +4056,32 @@
        break;;
   esac
 done
-else
-  $as_echo "$as_me: failed program was:" >&5
+else $as_nop
+  printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "cannot compute suffix of object files: cannot compile
 See \`config.log' for more details" "$LINENO" 5; }
 fi
 rm -f conftest.$ac_cv_objext conftest.$ac_ext
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_objext" >&5
-$as_echo "$ac_cv_objext" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_objext" >&5
+printf "%s\n" "$ac_cv_objext" >&6; }
 OBJEXT=$ac_cv_objext
 ac_objext=$OBJEXT
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether we are using the GNU C compiler" >&5
-$as_echo_n "checking whether we are using the GNU C compiler... " >&6; }
-if ${ac_cv_c_compiler_gnu+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the compiler supports GNU C" >&5
+printf %s "checking whether the compiler supports GNU C... " >&6; }
+if test ${ac_cv_c_compiler_gnu+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 #ifndef __GNUC__
        choke me
@@ -3560,29 +4091,33 @@
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_compiler_gnu=yes
-else
+else $as_nop
   ac_compiler_gnu=no
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 ac_cv_c_compiler_gnu=$ac_compiler_gnu
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_compiler_gnu" >&5
-$as_echo "$ac_cv_c_compiler_gnu" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_compiler_gnu" >&5
+printf "%s\n" "$ac_cv_c_compiler_gnu" >&6; }
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
 if test $ac_compiler_gnu = yes; then
   GCC=yes
 else
   GCC=
 fi
-ac_test_CFLAGS=${CFLAGS+set}
+ac_test_CFLAGS=${CFLAGS+y}
 ac_save_CFLAGS=$CFLAGS
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC accepts -g" >&5
-$as_echo_n "checking whether $CC accepts -g... " >&6; }
-if ${ac_cv_prog_cc_g+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC accepts -g" >&5
+printf %s "checking whether $CC accepts -g... " >&6; }
+if test ${ac_cv_prog_cc_g+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_save_c_werror_flag=$ac_c_werror_flag
    ac_c_werror_flag=yes
    ac_cv_prog_cc_g=no
@@ -3591,57 +4126,60 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_g=yes
-else
+else $as_nop
   CFLAGS=""
       cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
 
-else
+else $as_nop
   ac_c_werror_flag=$ac_save_c_werror_flag
 	 CFLAGS="-g"
 	 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_g=yes
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
    ac_c_werror_flag=$ac_save_c_werror_flag
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_g" >&5
-$as_echo "$ac_cv_prog_cc_g" >&6; }
-if test "$ac_test_CFLAGS" = set; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_g" >&5
+printf "%s\n" "$ac_cv_prog_cc_g" >&6; }
+if test $ac_test_CFLAGS; then
   CFLAGS=$ac_save_CFLAGS
 elif test $ac_cv_prog_cc_g = yes; then
   if test "$GCC" = yes; then
@@ -3656,94 +4194,144 @@
     CFLAGS=
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $CC option to accept ISO C89" >&5
-$as_echo_n "checking for $CC option to accept ISO C89... " >&6; }
-if ${ac_cv_prog_cc_c89+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+ac_prog_cc_stdc=no
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C11 features" >&5
+printf %s "checking for $CC option to enable C11 features... " >&6; }
+if test ${ac_cv_prog_cc_c11+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  ac_cv_prog_cc_c11=no
+ac_save_CC=$CC
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+$ac_c_conftest_c11_program
+_ACEOF
+for ac_arg in '' -std=gnu11
+do
+  CC="$ac_save_CC $ac_arg"
+  if ac_fn_c_try_compile "$LINENO"
+then :
+  ac_cv_prog_cc_c11=$ac_arg
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam
+  test "x$ac_cv_prog_cc_c11" != "xno" && break
+done
+rm -f conftest.$ac_ext
+CC=$ac_save_CC
+fi
+
+if test "x$ac_cv_prog_cc_c11" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else $as_nop
+  if test "x$ac_cv_prog_cc_c11" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c11" >&5
+printf "%s\n" "$ac_cv_prog_cc_c11" >&6; }
+     CC="$CC $ac_cv_prog_cc_c11"
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c11
+  ac_prog_cc_stdc=c11
+fi
+fi
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C99 features" >&5
+printf %s "checking for $CC option to enable C99 features... " >&6; }
+if test ${ac_cv_prog_cc_c99+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  ac_cv_prog_cc_c99=no
+ac_save_CC=$CC
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+$ac_c_conftest_c99_program
+_ACEOF
+for ac_arg in '' -std=gnu99 -std=c99 -c99 -qlanglvl=extc1x -qlanglvl=extc99 -AC99 -D_STDC_C99=
+do
+  CC="$ac_save_CC $ac_arg"
+  if ac_fn_c_try_compile "$LINENO"
+then :
+  ac_cv_prog_cc_c99=$ac_arg
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam
+  test "x$ac_cv_prog_cc_c99" != "xno" && break
+done
+rm -f conftest.$ac_ext
+CC=$ac_save_CC
+fi
+
+if test "x$ac_cv_prog_cc_c99" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else $as_nop
+  if test "x$ac_cv_prog_cc_c99" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c99" >&5
+printf "%s\n" "$ac_cv_prog_cc_c99" >&6; }
+     CC="$CC $ac_cv_prog_cc_c99"
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c99
+  ac_prog_cc_stdc=c99
+fi
+fi
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C89 features" >&5
+printf %s "checking for $CC option to enable C89 features... " >&6; }
+if test ${ac_cv_prog_cc_c89+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_cv_prog_cc_c89=no
 ac_save_CC=$CC
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#include <stdarg.h>
-#include <stdio.h>
-struct stat;
-/* Most of the following tests are stolen from RCS 5.7's src/conf.sh.  */
-struct buf { int x; };
-FILE * (*rcsopen) (struct buf *, struct stat *, int);
-static char *e (p, i)
-     char **p;
-     int i;
-{
-  return p[i];
-}
-static char *f (char * (*g) (char **, int), char **p, ...)
-{
-  char *s;
-  va_list v;
-  va_start (v,p);
-  s = g (p, va_arg (v,int));
-  va_end (v);
-  return s;
-}
-
-/* OSF 4.0 Compaq cc is some sort of almost-ANSI by default.  It has
-   function prototypes and stuff, but not '\xHH' hex character constants.
-   These don't provoke an error unfortunately, instead are silently treated
-   as 'x'.  The following induces an error, until -std is added to get
-   proper ANSI mode.  Curiously '\x00'!='x' always comes out true, for an
-   array size at least.  It's necessary to write '\x00'==0 to get something
-   that's true only with -std.  */
-int osf4_cc_array ['\x00' == 0 ? 1 : -1];
-
-/* IBM C 6 for AIX is almost-ANSI by default, but it replaces macro parameters
-   inside strings and character constants.  */
-#define FOO(x) 'x'
-int xlc6_cc_array[FOO(a) == 'x' ? 1 : -1];
-
-int test (int i, double x);
-struct s1 {int (*f) (int a);};
-struct s2 {int (*f) (double a);};
-int pairnames (int, char **, FILE *(*)(struct buf *, struct stat *, int), int, int);
-int argc;
-char **argv;
-int
-main ()
-{
-return f (e, argv, 0) != argv[0]  ||  f (e, argv, 1) != argv[1];
-  ;
-  return 0;
-}
+$ac_c_conftest_c89_program
 _ACEOF
-for ac_arg in '' -qlanglvl=extc89 -qlanglvl=ansi -std \
-	-Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
+for ac_arg in '' -qlanglvl=extc89 -qlanglvl=ansi -std -Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
 do
   CC="$ac_save_CC $ac_arg"
-  if ac_fn_c_try_compile "$LINENO"; then :
+  if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_c89=$ac_arg
 fi
-rm -f core conftest.err conftest.$ac_objext
+rm -f core conftest.err conftest.$ac_objext conftest.beam
   test "x$ac_cv_prog_cc_c89" != "xno" && break
 done
 rm -f conftest.$ac_ext
 CC=$ac_save_CC
-
 fi
-# AC_CACHE_VAL
-case "x$ac_cv_prog_cc_c89" in
-  x)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
-$as_echo "none needed" >&6; } ;;
-  xno)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
-$as_echo "unsupported" >&6; } ;;
-  *)
-    CC="$CC $ac_cv_prog_cc_c89"
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c89" >&5
-$as_echo "$ac_cv_prog_cc_c89" >&6; } ;;
-esac
-if test "x$ac_cv_prog_cc_c89" != xno; then :
 
+if test "x$ac_cv_prog_cc_c89" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else $as_nop
+  if test "x$ac_cv_prog_cc_c89" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c89" >&5
+printf "%s\n" "$ac_cv_prog_cc_c89" >&6; }
+     CC="$CC $ac_cv_prog_cc_c89"
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c89
+  ac_prog_cc_stdc=c89
+fi
 fi
 
 ac_ext=c
@@ -3752,21 +4340,23 @@
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
-ac_ext=c
+
+  ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC understands -c and -o together" >&5
-$as_echo_n "checking whether $CC understands -c and -o together... " >&6; }
-if ${am_cv_prog_cc_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC understands -c and -o together" >&5
+printf %s "checking whether $CC understands -c and -o together... " >&6; }
+if test ${am_cv_prog_cc_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3794,8 +4384,8 @@
   rm -f core conftest*
   unset am_i
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_prog_cc_c_o" >&5
-$as_echo "$am_cv_prog_cc_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_prog_cc_c_o" >&5
+printf "%s\n" "$am_cv_prog_cc_c_o" >&6; }
 if test "$am_cv_prog_cc_c_o" != yes; then
    # Losing compiler, so override with the script.
    # FIXME: It is wrong to rewrite CC.
@@ -3814,8 +4404,8 @@
 
 ac_config_commands="$ac_config_commands depfiles"
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
-$as_echo_n "checking whether ${MAKE-make} supports the include directive... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
+printf %s "checking whether ${MAKE-make} supports the include directive... " >&6; }
 cat > confinc.mk << 'END'
 am__doit:
 	@echo this is the am__doit target >confinc.out
@@ -3851,11 +4441,12 @@
   fi
 done
 rm -f confinc.* confmf.*
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
-$as_echo "${_am_result}" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
+printf "%s\n" "${_am_result}" >&6; }
 
 # Check whether --enable-dependency-tracking was given.
-if test "${enable_dependency_tracking+set}" = set; then :
+if test ${enable_dependency_tracking+y}
+then :
   enableval=$enable_dependency_tracking;
 fi
 
@@ -3876,11 +4467,12 @@
 
 depcc="$CC"   am_compiler_list=
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CC_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
+printf %s "checking dependency style of $depcc... " >&6; }
+if test ${am_cv_CC_dependencies_compiler_type+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
   # We make a subdir and do the tests there.  Otherwise we can end up
   # making bogus files that we don't know about and never remove.  For
@@ -3987,8 +4579,8 @@
 fi
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CC_dependencies_compiler_type" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
+printf "%s\n" "$am_cv_CC_dependencies_compiler_type" >&6; }
 CCDEPMODE=depmode=$am_cv_CC_dependencies_compiler_type
 
  if
@@ -4011,11 +4603,12 @@
 
 depcc="$CCAS"   am_compiler_list=
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CCAS_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
+printf %s "checking dependency style of $depcc... " >&6; }
+if test ${am_cv_CCAS_dependencies_compiler_type+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
   # We make a subdir and do the tests there.  Otherwise we can end up
   # making bogus files that we don't know about and never remove.  For
@@ -4120,8 +4713,8 @@
 fi
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CCAS_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CCAS_dependencies_compiler_type" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_CCAS_dependencies_compiler_type" >&5
+printf "%s\n" "$am_cv_CCAS_dependencies_compiler_type" >&6; }
 CCASDEPMODE=depmode=$am_cv_CCAS_dependencies_compiler_type
 
  if
@@ -4135,26 +4728,29 @@
 fi
 
 
-# Make sure we can run config.sub.
-$SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
-  as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
-$as_echo_n "checking build system type... " >&6; }
-if ${ac_cv_build+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+
+  # Make sure we can run config.sub.
+$SHELL "${ac_aux_dir}config.sub" sun4 >/dev/null 2>&1 ||
+  as_fn_error $? "cannot run $SHELL ${ac_aux_dir}config.sub" "$LINENO" 5
+
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
+printf %s "checking build system type... " >&6; }
+if test ${ac_cv_build+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_build_alias=$build_alias
 test "x$ac_build_alias" = x &&
-  ac_build_alias=`$SHELL "$ac_aux_dir/config.guess"`
+  ac_build_alias=`$SHELL "${ac_aux_dir}config.guess"`
 test "x$ac_build_alias" = x &&
   as_fn_error $? "cannot guess build type; you must specify one" "$LINENO" 5
-ac_cv_build=`$SHELL "$ac_aux_dir/config.sub" $ac_build_alias` ||
-  as_fn_error $? "$SHELL $ac_aux_dir/config.sub $ac_build_alias failed" "$LINENO" 5
+ac_cv_build=`$SHELL "${ac_aux_dir}config.sub" $ac_build_alias` ||
+  as_fn_error $? "$SHELL ${ac_aux_dir}config.sub $ac_build_alias failed" "$LINENO" 5
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
-$as_echo "$ac_cv_build" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
+printf "%s\n" "$ac_cv_build" >&6; }
 case $ac_cv_build in
 *-*-*) ;;
 *) as_fn_error $? "invalid value of canonical build" "$LINENO" 5;;
@@ -4173,21 +4769,22 @@
 case $build_os in *\ *) build_os=`echo "$build_os" | sed 's/ /-/g'`;; esac
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
-$as_echo_n "checking host system type... " >&6; }
-if ${ac_cv_host+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
+printf %s "checking host system type... " >&6; }
+if test ${ac_cv_host+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test "x$host_alias" = x; then
   ac_cv_host=$ac_cv_build
 else
-  ac_cv_host=`$SHELL "$ac_aux_dir/config.sub" $host_alias` ||
-    as_fn_error $? "$SHELL $ac_aux_dir/config.sub $host_alias failed" "$LINENO" 5
+  ac_cv_host=`$SHELL "${ac_aux_dir}config.sub" $host_alias` ||
+    as_fn_error $? "$SHELL ${ac_aux_dir}config.sub $host_alias failed" "$LINENO" 5
 fi
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
-$as_echo "$ac_cv_host" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
+printf "%s\n" "$ac_cv_host" >&6; }
 case $ac_cv_host in
 *-*-*) ;;
 *) as_fn_error $? "invalid value of canonical host" "$LINENO" 5;;
@@ -4206,11 +4803,12 @@
 case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a sed that does not truncate output" >&5
-$as_echo_n "checking for a sed that does not truncate output... " >&6; }
-if ${ac_cv_path_SED+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a sed that does not truncate output" >&5
+printf %s "checking for a sed that does not truncate output... " >&6; }
+if test ${ac_cv_path_SED+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
             ac_script=s/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb/
      for ac_i in 1 2 3 4 5 6 7; do
        ac_script="$ac_script$as_nl$ac_script"
@@ -4224,10 +4822,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in sed gsed; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in sed gsed
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_SED="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_SED="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_SED" || continue
 # Check for GNU ac_path_SED and select it if it is found.
   # Check for GNU $ac_path_SED
@@ -4236,13 +4839,13 @@
   ac_cv_path_SED="$ac_path_SED" ac_path_SED_found=:;;
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo '' >> "conftest.nl"
+    printf "%s\n" '' >> "conftest.nl"
     "$ac_path_SED" -f conftest.sed < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4270,8 +4873,8 @@
 fi
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_SED" >&5
-$as_echo "$ac_cv_path_SED" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_SED" >&5
+printf "%s\n" "$ac_cv_path_SED" >&6; }
  SED="$ac_cv_path_SED"
   rm -f conftest.sed
 
@@ -4288,11 +4891,12 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for grep that handles long lines and -e" >&5
-$as_echo_n "checking for grep that handles long lines and -e... " >&6; }
-if ${ac_cv_path_GREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for grep that handles long lines and -e" >&5
+printf %s "checking for grep that handles long lines and -e... " >&6; }
+if test ${ac_cv_path_GREP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -z "$GREP"; then
   ac_path_GREP_found=false
   # Loop through the user's path and test for each of PROGNAME-LIST
@@ -4300,10 +4904,15 @@
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in grep ggrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in grep ggrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_GREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_GREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_GREP" || continue
 # Check for GNU ac_path_GREP and select it if it is found.
   # Check for GNU $ac_path_GREP
@@ -4312,13 +4921,13 @@
   ac_cv_path_GREP="$ac_path_GREP" ac_path_GREP_found=:;;
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'GREP' >> "conftest.nl"
+    printf "%s\n" 'GREP' >> "conftest.nl"
     "$ac_path_GREP" -e 'GREP$' -e '-(cannot match)-' < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4346,16 +4955,17 @@
 fi
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_GREP" >&5
-$as_echo "$ac_cv_path_GREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_GREP" >&5
+printf "%s\n" "$ac_cv_path_GREP" >&6; }
  GREP="$ac_cv_path_GREP"
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for egrep" >&5
-$as_echo_n "checking for egrep... " >&6; }
-if ${ac_cv_path_EGREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for egrep" >&5
+printf %s "checking for egrep... " >&6; }
+if test ${ac_cv_path_EGREP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if echo a | $GREP -E '(a|b)' >/dev/null 2>&1
    then ac_cv_path_EGREP="$GREP -E"
    else
@@ -4366,10 +4976,15 @@
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in egrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in egrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_EGREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_EGREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_EGREP" || continue
 # Check for GNU ac_path_EGREP and select it if it is found.
   # Check for GNU $ac_path_EGREP
@@ -4378,13 +4993,13 @@
   ac_cv_path_EGREP="$ac_path_EGREP" ac_path_EGREP_found=:;;
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'EGREP' >> "conftest.nl"
+    printf "%s\n" 'EGREP' >> "conftest.nl"
     "$ac_path_EGREP" 'EGREP$' < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4413,16 +5028,17 @@
 
    fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_EGREP" >&5
-$as_echo "$ac_cv_path_EGREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_EGREP" >&5
+printf "%s\n" "$ac_cv_path_EGREP" >&6; }
  EGREP="$ac_cv_path_EGREP"
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for fgrep" >&5
-$as_echo_n "checking for fgrep... " >&6; }
-if ${ac_cv_path_FGREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for fgrep" >&5
+printf %s "checking for fgrep... " >&6; }
+if test ${ac_cv_path_FGREP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if echo 'ab*c' | $GREP -F 'ab*c' >/dev/null 2>&1
    then ac_cv_path_FGREP="$GREP -F"
    else
@@ -4433,10 +5049,15 @@
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in fgrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in fgrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_FGREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_FGREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_FGREP" || continue
 # Check for GNU ac_path_FGREP and select it if it is found.
   # Check for GNU $ac_path_FGREP
@@ -4445,13 +5066,13 @@
   ac_cv_path_FGREP="$ac_path_FGREP" ac_path_FGREP_found=:;;
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'FGREP' >> "conftest.nl"
+    printf "%s\n" 'FGREP' >> "conftest.nl"
     "$ac_path_FGREP" FGREP < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4480,8 +5101,8 @@
 
    fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_FGREP" >&5
-$as_echo "$ac_cv_path_FGREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_FGREP" >&5
+printf "%s\n" "$ac_cv_path_FGREP" >&6; }
  FGREP="$ac_cv_path_FGREP"
 
 
@@ -4507,8 +5128,8 @@
 ECHO=$ECHO$ECHO$ECHO$ECHO$ECHO
 ECHO=$ECHO$ECHO$ECHO$ECHO$ECHO$ECHO
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to print strings" >&5
-$as_echo_n "checking how to print strings... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to print strings" >&5
+printf %s "checking how to print strings... " >&6; }
 # Test print first, because it will be a builtin if present.
 if test "X`( print -r -- -n ) 2>/dev/null`" = X-n && \
    test "X`print -r -- $ECHO 2>/dev/null`" = "X$ECHO"; then
@@ -4534,12 +5155,12 @@
 }
 
 case $ECHO in
-  printf*) { $as_echo "$as_me:${as_lineno-$LINENO}: result: printf" >&5
-$as_echo "printf" >&6; } ;;
-  print*) { $as_echo "$as_me:${as_lineno-$LINENO}: result: print -r" >&5
-$as_echo "print -r" >&6; } ;;
-  *) { $as_echo "$as_me:${as_lineno-$LINENO}: result: cat" >&5
-$as_echo "cat" >&6; } ;;
+  printf*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: printf" >&5
+printf "%s\n" "printf" >&6; } ;;
+  print*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: print -r" >&5
+printf "%s\n" "print -r" >&6; } ;;
+  *) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: cat" >&5
+printf "%s\n" "cat" >&6; } ;;
 esac
 
 
@@ -4558,17 +5179,18 @@
 
 
 # Check whether --with-gnu-ld was given.
-if test "${with_gnu_ld+set}" = set; then :
+if test ${with_gnu_ld+y}
+then :
   withval=$with_gnu_ld; test no = "$withval" || with_gnu_ld=yes
-else
+else $as_nop
   with_gnu_ld=no
 fi
 
 ac_prog=ld
 if test yes = "$GCC"; then
   # Check if gcc -print-prog-name=ld gives a path.
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ld used by $CC" >&5
-$as_echo_n "checking for ld used by $CC... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ld used by $CC" >&5
+printf %s "checking for ld used by $CC... " >&6; }
   case $host in
   *-*-mingw*)
     # gcc leaves a trailing carriage return, which upsets mingw
@@ -4597,15 +5219,16 @@
     ;;
   esac
 elif test yes = "$with_gnu_ld"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GNU ld" >&5
-$as_echo_n "checking for GNU ld... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for GNU ld" >&5
+printf %s "checking for GNU ld... " >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for non-GNU ld" >&5
-$as_echo_n "checking for non-GNU ld... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for non-GNU ld" >&5
+printf %s "checking for non-GNU ld... " >&6; }
 fi
-if ${lt_cv_path_LD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+if test ${lt_cv_path_LD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -z "$LD"; then
   lt_save_ifs=$IFS; IFS=$PATH_SEPARATOR
   for ac_dir in $PATH; do
@@ -4634,18 +5257,19 @@
 
 LD=$lt_cv_path_LD
 if test -n "$LD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $LD" >&5
-$as_echo "$LD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $LD" >&5
+printf "%s\n" "$LD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 test -z "$LD" && as_fn_error $? "no acceptable ld found in \$PATH" "$LINENO" 5
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if the linker ($LD) is GNU ld" >&5
-$as_echo_n "checking if the linker ($LD) is GNU ld... " >&6; }
-if ${lt_cv_prog_gnu_ld+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if the linker ($LD) is GNU ld" >&5
+printf %s "checking if the linker ($LD) is GNU ld... " >&6; }
+if test ${lt_cv_prog_gnu_ld+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   # I'd rather use --version here, but apparently some GNU lds only accept -v.
 case `$LD -v 2>&1 </dev/null` in
 *GNU* | *'with BFD'*)
@@ -4656,8 +5280,8 @@
   ;;
 esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_gnu_ld" >&5
-$as_echo "$lt_cv_prog_gnu_ld" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_gnu_ld" >&5
+printf "%s\n" "$lt_cv_prog_gnu_ld" >&6; }
 with_gnu_ld=$lt_cv_prog_gnu_ld
 
 
@@ -4673,40 +5297,36 @@
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to run the C preprocessor" >&5
-$as_echo_n "checking how to run the C preprocessor... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to run the C preprocessor" >&5
+printf %s "checking how to run the C preprocessor... " >&6; }
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
 fi
 if test -z "$CPP"; then
-  if ${ac_cv_prog_CPP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-      # Double quotes because CPP needs to be expanded
-    for CPP in "$CC -E" "$CC -E -traditional-cpp" "/lib/cpp"
+  if test ${ac_cv_prog_CPP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+      # Double quotes because $CC needs to be expanded
+    for CPP in "$CC -E" "$CC -E -traditional-cpp" cpp /lib/cpp
     do
       ac_preproc_ok=false
 for ac_c_preproc_warn_flag in '' yes
 do
   # Use a header file that comes with gcc, so configuring glibc
   # with a fresh cross-compiler works.
-  # Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-  # <limits.h> exists even on freestanding compilers.
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp. "Syntax error" is here to catch this case.
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
+#include <limits.h>
 		     Syntax error
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
 
-else
+else $as_nop
   # Broken: fails on valid input.
 continue
 fi
@@ -4718,10 +5338,11 @@
 /* end confdefs.h.  */
 #include <ac_nonexistent.h>
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
   # Broken: success on invalid input.
 continue
-else
+else $as_nop
   # Passes both tests.
 ac_preproc_ok=:
 break
@@ -4731,7 +5352,8 @@
 done
 # Because of `break', _AC_PREPROC_IFELSE's cleaning code was skipped.
 rm -f conftest.i conftest.err conftest.$ac_ext
-if $ac_preproc_ok; then :
+if $ac_preproc_ok
+then :
   break
 fi
 
@@ -4743,29 +5365,24 @@
 else
   ac_cv_prog_CPP=$CPP
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $CPP" >&5
-$as_echo "$CPP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CPP" >&5
+printf "%s\n" "$CPP" >&6; }
 ac_preproc_ok=false
 for ac_c_preproc_warn_flag in '' yes
 do
   # Use a header file that comes with gcc, so configuring glibc
   # with a fresh cross-compiler works.
-  # Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-  # <limits.h> exists even on freestanding compilers.
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp. "Syntax error" is here to catch this case.
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
+#include <limits.h>
 		     Syntax error
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
 
-else
+else $as_nop
   # Broken: fails on valid input.
 continue
 fi
@@ -4777,10 +5394,11 @@
 /* end confdefs.h.  */
 #include <ac_nonexistent.h>
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
   # Broken: success on invalid input.
 continue
-else
+else $as_nop
   # Passes both tests.
 ac_preproc_ok=:
 break
@@ -4790,11 +5408,12 @@
 done
 # Because of `break', _AC_PREPROC_IFELSE's cleaning code was skipped.
 rm -f conftest.i conftest.err conftest.$ac_ext
-if $ac_preproc_ok; then :
+if $ac_preproc_ok
+then :
 
-else
-  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+else $as_nop
+  { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "C preprocessor \"$CPP\" fails sanity check
 See \`config.log' for more details" "$LINENO" 5; }
 fi
@@ -4809,11 +5428,12 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AWK+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AWK+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$AWK"; then
   ac_cv_prog_AWK="$AWK" # Let the user override the test.
 else
@@ -4821,11 +5441,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AWK="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -4836,11 +5460,11 @@
 fi
 AWK=$ac_cv_prog_AWK
 if test -n "$AWK"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
-$as_echo "$AWK" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
+printf "%s\n" "$AWK" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -4848,24 +5472,25 @@
 done
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ln -s works" >&5
-$as_echo_n "checking whether ln -s works... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ln -s works" >&5
+printf %s "checking whether ln -s works... " >&6; }
 LN_S=$as_ln_s
 if test "$LN_S" = "ln -s"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no, using $LN_S" >&5
-$as_echo "no, using $LN_S" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no, using $LN_S" >&5
+printf "%s\n" "no, using $LN_S" >&6; }
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
-$as_echo_n "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
+printf %s "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
 set x ${MAKE-make}
-ac_make=`$as_echo "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
-if eval \${ac_cv_prog_make_${ac_make}_set+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+ac_make=`printf "%s\n" "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
+if eval test \${ac_cv_prog_make_${ac_make}_set+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat >conftest.make <<\_ACEOF
 SHELL = /bin/sh
 all:
@@ -4881,26 +5506,27 @@
 rm -f conftest.make
 fi
 if eval test \$ac_cv_prog_make_${ac_make}_set = yes; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
   SET_MAKE=
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
   SET_MAKE="MAKE=${MAKE-make}"
 fi
 
 
 case `pwd` in
   *\ * | *\	*)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&5
-$as_echo "$as_me: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&2;} ;;
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&5
+printf "%s\n" "$as_me: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&2;} ;;
 esac
 
 
 
-macro_version='2.4.6'
-macro_revision='2.4.6'
+macro_version='2.4.7'
+macro_revision='2.4.7'
+
 
 
 
@@ -4933,11 +5559,12 @@
 # Sed substitution to avoid accidental globbing in evaled expressions
 no_glob_subst='s/\*/\\\*/g'
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for BSD- or MS-compatible name lister (nm)" >&5
-$as_echo_n "checking for BSD- or MS-compatible name lister (nm)... " >&6; }
-if ${lt_cv_path_NM+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for BSD- or MS-compatible name lister (nm)" >&5
+printf %s "checking for BSD- or MS-compatible name lister (nm)... " >&6; }
+if test ${lt_cv_path_NM+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$NM"; then
   # Let the user override the test.
   lt_cv_path_NM=$NM
@@ -4962,13 +5589,13 @@
 	mingw*) lt_bad_file=conftest.nm/nofile ;;
 	*) lt_bad_file=/dev/null ;;
 	esac
-	case `"$tmp_nm" -B $lt_bad_file 2>&1 | sed '1q'` in
+	case `"$tmp_nm" -B $lt_bad_file 2>&1 | $SED '1q'` in
 	*$lt_bad_file* | *'Invalid file or object type'*)
 	  lt_cv_path_NM="$tmp_nm -B"
 	  break 2
 	  ;;
 	*)
-	  case `"$tmp_nm" -p /dev/null 2>&1 | sed '1q'` in
+	  case `"$tmp_nm" -p /dev/null 2>&1 | $SED '1q'` in
 	  */dev/null*)
 	    lt_cv_path_NM="$tmp_nm -p"
 	    break 2
@@ -4987,8 +5614,8 @@
   : ${lt_cv_path_NM=no}
 fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_NM" >&5
-$as_echo "$lt_cv_path_NM" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_NM" >&5
+printf "%s\n" "$lt_cv_path_NM" >&6; }
 if test no != "$lt_cv_path_NM"; then
   NM=$lt_cv_path_NM
 else
@@ -5001,11 +5628,12 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DUMPBIN+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DUMPBIN+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$DUMPBIN"; then
   ac_cv_prog_DUMPBIN="$DUMPBIN" # Let the user override the test.
 else
@@ -5013,11 +5641,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DUMPBIN="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5028,11 +5660,11 @@
 fi
 DUMPBIN=$ac_cv_prog_DUMPBIN
 if test -n "$DUMPBIN"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DUMPBIN" >&5
-$as_echo "$DUMPBIN" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DUMPBIN" >&5
+printf "%s\n" "$DUMPBIN" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5045,11 +5677,12 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DUMPBIN+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DUMPBIN+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_DUMPBIN"; then
   ac_cv_prog_ac_ct_DUMPBIN="$ac_ct_DUMPBIN" # Let the user override the test.
 else
@@ -5057,11 +5690,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DUMPBIN="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5072,11 +5709,11 @@
 fi
 ac_ct_DUMPBIN=$ac_cv_prog_ac_ct_DUMPBIN
 if test -n "$ac_ct_DUMPBIN"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DUMPBIN" >&5
-$as_echo "$ac_ct_DUMPBIN" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DUMPBIN" >&5
+printf "%s\n" "$ac_ct_DUMPBIN" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5088,15 +5725,15 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DUMPBIN=$ac_ct_DUMPBIN
   fi
 fi
 
-    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | sed '1q'` in
+    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | $SED '1q'` in
     *COFF*)
       DUMPBIN="$DUMPBIN -symbols -headers"
       ;;
@@ -5117,11 +5754,12 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the name lister ($NM) interface" >&5
-$as_echo_n "checking the name lister ($NM) interface... " >&6; }
-if ${lt_cv_nm_interface+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking the name lister ($NM) interface" >&5
+printf %s "checking the name lister ($NM) interface... " >&6; }
+if test ${lt_cv_nm_interface+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_nm_interface="BSD nm"
   echo "int some_variable = 0;" > conftest.$ac_ext
   (eval echo "\"\$as_me:$LINENO: $ac_compile\"" >&5)
@@ -5137,15 +5775,16 @@
   fi
   rm -f conftest*
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_nm_interface" >&5
-$as_echo "$lt_cv_nm_interface" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_nm_interface" >&5
+printf "%s\n" "$lt_cv_nm_interface" >&6; }
 
 # find the maximum length of command line arguments
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the maximum length of command line arguments" >&5
-$as_echo_n "checking the maximum length of command line arguments... " >&6; }
-if ${lt_cv_sys_max_cmd_len+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking the maximum length of command line arguments" >&5
+printf %s "checking the maximum length of command line arguments... " >&6; }
+if test ${lt_cv_sys_max_cmd_len+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
     i=0
   teststring=ABCD
 
@@ -5187,7 +5826,7 @@
     lt_cv_sys_max_cmd_len=8192;
     ;;
 
-  bitrig* | darwin* | dragonfly* | freebsd* | netbsd* | openbsd*)
+  bitrig* | darwin* | dragonfly* | freebsd* | midnightbsd* | netbsd* | openbsd*)
     # This has been around since 386BSD, at least.  Likely further.
     if test -x /sbin/sysctl; then
       lt_cv_sys_max_cmd_len=`/sbin/sysctl -n kern.argmax`
@@ -5230,7 +5869,7 @@
   sysv5* | sco5v6* | sysv4.2uw2*)
     kargmax=`grep ARG_MAX /etc/conf/cf.d/stune 2>/dev/null`
     if test -n "$kargmax"; then
-      lt_cv_sys_max_cmd_len=`echo $kargmax | sed 's/.*[	 ]//'`
+      lt_cv_sys_max_cmd_len=`echo $kargmax | $SED 's/.*[	 ]//'`
     else
       lt_cv_sys_max_cmd_len=32768
     fi
@@ -5272,11 +5911,11 @@
 fi
 
 if test -n "$lt_cv_sys_max_cmd_len"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sys_max_cmd_len" >&5
-$as_echo "$lt_cv_sys_max_cmd_len" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sys_max_cmd_len" >&5
+printf "%s\n" "$lt_cv_sys_max_cmd_len" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: none" >&5
-$as_echo "none" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none" >&5
+printf "%s\n" "none" >&6; }
 fi
 max_cmd_len=$lt_cv_sys_max_cmd_len
 
@@ -5320,11 +5959,12 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to $host format" >&5
-$as_echo_n "checking how to convert $build file names to $host format... " >&6; }
-if ${lt_cv_to_host_file_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to $host format" >&5
+printf %s "checking how to convert $build file names to $host format... " >&6; }
+if test ${lt_cv_to_host_file_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   case $host in
   *-*-mingw* )
     case $build in
@@ -5360,18 +6000,19 @@
 fi
 
 to_host_file_cmd=$lt_cv_to_host_file_cmd
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_host_file_cmd" >&5
-$as_echo "$lt_cv_to_host_file_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_host_file_cmd" >&5
+printf "%s\n" "$lt_cv_to_host_file_cmd" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to toolchain format" >&5
-$as_echo_n "checking how to convert $build file names to toolchain format... " >&6; }
-if ${lt_cv_to_tool_file_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to toolchain format" >&5
+printf %s "checking how to convert $build file names to toolchain format... " >&6; }
+if test ${lt_cv_to_tool_file_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   #assume ordinary cross tools, or native build.
 lt_cv_to_tool_file_cmd=func_convert_file_noop
 case $host in
@@ -5387,22 +6028,23 @@
 fi
 
 to_tool_file_cmd=$lt_cv_to_tool_file_cmd
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_tool_file_cmd" >&5
-$as_echo "$lt_cv_to_tool_file_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_tool_file_cmd" >&5
+printf "%s\n" "$lt_cv_to_tool_file_cmd" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $LD option to reload object files" >&5
-$as_echo_n "checking for $LD option to reload object files... " >&6; }
-if ${lt_cv_ld_reload_flag+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $LD option to reload object files" >&5
+printf %s "checking for $LD option to reload object files... " >&6; }
+if test ${lt_cv_ld_reload_flag+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_ld_reload_flag='-r'
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_reload_flag" >&5
-$as_echo "$lt_cv_ld_reload_flag" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_reload_flag" >&5
+printf "%s\n" "$lt_cv_ld_reload_flag" >&6; }
 reload_flag=$lt_cv_ld_reload_flag
 case $reload_flag in
 "" | " "*) ;;
@@ -5433,13 +6075,122 @@
 
 
 if test -n "$ac_tool_prefix"; then
+  # Extract the first word of "${ac_tool_prefix}file", so it can be a program name with args.
+set dummy ${ac_tool_prefix}file; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_FILECMD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  if test -n "$FILECMD"; then
+  ac_cv_prog_FILECMD="$FILECMD" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_FILECMD="${ac_tool_prefix}file"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+FILECMD=$ac_cv_prog_FILECMD
+if test -n "$FILECMD"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $FILECMD" >&5
+printf "%s\n" "$FILECMD" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+
+fi
+if test -z "$ac_cv_prog_FILECMD"; then
+  ac_ct_FILECMD=$FILECMD
+  # Extract the first word of "file", so it can be a program name with args.
+set dummy file; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_FILECMD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
+  if test -n "$ac_ct_FILECMD"; then
+  ac_cv_prog_ac_ct_FILECMD="$ac_ct_FILECMD" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_ac_ct_FILECMD="file"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+ac_ct_FILECMD=$ac_cv_prog_ac_ct_FILECMD
+if test -n "$ac_ct_FILECMD"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_FILECMD" >&5
+printf "%s\n" "$ac_ct_FILECMD" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+  if test "x$ac_ct_FILECMD" = x; then
+    FILECMD=":"
+  else
+    case $cross_compiling:$ac_tool_warned in
+yes:)
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+ac_tool_warned=yes ;;
+esac
+    FILECMD=$ac_ct_FILECMD
+  fi
+else
+  FILECMD="$ac_cv_prog_FILECMD"
+fi
+
+
+
+
+
+
+
+if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}objdump", so it can be a program name with args.
 set dummy ${ac_tool_prefix}objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$OBJDUMP"; then
   ac_cv_prog_OBJDUMP="$OBJDUMP" # Let the user override the test.
 else
@@ -5447,11 +6198,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OBJDUMP="${ac_tool_prefix}objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5462,11 +6217,11 @@
 fi
 OBJDUMP=$ac_cv_prog_OBJDUMP
 if test -n "$OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
-$as_echo "$OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
+printf "%s\n" "$OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5475,11 +6230,12 @@
   ac_ct_OBJDUMP=$OBJDUMP
   # Extract the first word of "objdump", so it can be a program name with args.
 set dummy objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_OBJDUMP"; then
   ac_cv_prog_ac_ct_OBJDUMP="$ac_ct_OBJDUMP" # Let the user override the test.
 else
@@ -5487,11 +6243,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OBJDUMP="objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5502,11 +6262,11 @@
 fi
 ac_ct_OBJDUMP=$ac_cv_prog_ac_ct_OBJDUMP
 if test -n "$ac_ct_OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
-$as_echo "$ac_ct_OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
+printf "%s\n" "$ac_ct_OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OBJDUMP" = x; then
@@ -5514,8 +6274,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OBJDUMP=$ac_ct_OBJDUMP
@@ -5531,11 +6291,12 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to recognize dependent libraries" >&5
-$as_echo_n "checking how to recognize dependent libraries... " >&6; }
-if ${lt_cv_deplibs_check_method+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to recognize dependent libraries" >&5
+printf %s "checking how to recognize dependent libraries... " >&6; }
+if test ${lt_cv_deplibs_check_method+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_file_magic_cmd='$MAGIC_CMD'
 lt_cv_file_magic_test_file=
 lt_cv_deplibs_check_method='unknown'
@@ -5561,7 +6322,7 @@
 
 bsdi[45]*)
   lt_cv_deplibs_check_method='file_magic ELF [0-9][0-9]*-bit [ML]SB (shared object|dynamic lib)'
-  lt_cv_file_magic_cmd='/usr/bin/file -L'
+  lt_cv_file_magic_cmd='$FILECMD -L'
   lt_cv_file_magic_test_file=/shlib/libc.so
   ;;
 
@@ -5595,14 +6356,14 @@
   lt_cv_deplibs_check_method=pass_all
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   if echo __ELF__ | $CC -E - | $GREP __ELF__ > /dev/null; then
     case $host_cpu in
     i*86 )
       # Not sure whether the presence of OpenBSD here was a mistake.
       # Let's accept both of them until this is cleared up.
       lt_cv_deplibs_check_method='file_magic (FreeBSD|OpenBSD|DragonFly)/i[3-9]86 (compact )?demand paged shared library'
-      lt_cv_file_magic_cmd=/usr/bin/file
+      lt_cv_file_magic_cmd=$FILECMD
       lt_cv_file_magic_test_file=`echo /usr/lib/libc.so.*`
       ;;
     esac
@@ -5616,7 +6377,7 @@
   ;;
 
 hpux10.20* | hpux11*)
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   case $host_cpu in
   ia64*)
     lt_cv_deplibs_check_method='file_magic (s[0-9][0-9][0-9]|ELF-[0-9][0-9]) shared object file - IA64'
@@ -5663,7 +6424,7 @@
 
 newos6*)
   lt_cv_deplibs_check_method='file_magic ELF [0-9][0-9]*-bit [ML]SB (executable|dynamic lib)'
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   lt_cv_file_magic_test_file=/usr/lib/libnls.so
   ;;
 
@@ -5731,8 +6492,8 @@
 esac
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_deplibs_check_method" >&5
-$as_echo "$lt_cv_deplibs_check_method" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_deplibs_check_method" >&5
+printf "%s\n" "$lt_cv_deplibs_check_method" >&6; }
 
 file_magic_glob=
 want_nocaseglob=no
@@ -5776,11 +6537,12 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dlltool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$DLLTOOL"; then
   ac_cv_prog_DLLTOOL="$DLLTOOL" # Let the user override the test.
 else
@@ -5788,11 +6550,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DLLTOOL="${ac_tool_prefix}dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5803,11 +6569,11 @@
 fi
 DLLTOOL=$ac_cv_prog_DLLTOOL
 if test -n "$DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
-$as_echo "$DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
+printf "%s\n" "$DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5816,11 +6582,12 @@
   ac_ct_DLLTOOL=$DLLTOOL
   # Extract the first word of "dlltool", so it can be a program name with args.
 set dummy dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_DLLTOOL"; then
   ac_cv_prog_ac_ct_DLLTOOL="$ac_ct_DLLTOOL" # Let the user override the test.
 else
@@ -5828,11 +6595,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DLLTOOL="dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5843,11 +6614,11 @@
 fi
 ac_ct_DLLTOOL=$ac_cv_prog_ac_ct_DLLTOOL
 if test -n "$ac_ct_DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
-$as_echo "$ac_ct_DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
+printf "%s\n" "$ac_ct_DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DLLTOOL" = x; then
@@ -5855,8 +6626,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DLLTOOL=$ac_ct_DLLTOOL
@@ -5873,11 +6644,12 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to associate runtime and link libraries" >&5
-$as_echo_n "checking how to associate runtime and link libraries... " >&6; }
-if ${lt_cv_sharedlib_from_linklib_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to associate runtime and link libraries" >&5
+printf %s "checking how to associate runtime and link libraries... " >&6; }
+if test ${lt_cv_sharedlib_from_linklib_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_sharedlib_from_linklib_cmd='unknown'
 
 case $host_os in
@@ -5900,8 +6672,8 @@
 esac
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sharedlib_from_linklib_cmd" >&5
-$as_echo "$lt_cv_sharedlib_from_linklib_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sharedlib_from_linklib_cmd" >&5
+printf "%s\n" "$lt_cv_sharedlib_from_linklib_cmd" >&6; }
 sharedlib_from_linklib_cmd=$lt_cv_sharedlib_from_linklib_cmd
 test -z "$sharedlib_from_linklib_cmd" && sharedlib_from_linklib_cmd=$ECHO
 
@@ -5917,11 +6689,12 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AR+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AR+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$AR"; then
   ac_cv_prog_AR="$AR" # Let the user override the test.
 else
@@ -5929,11 +6702,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AR="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5944,11 +6721,11 @@
 fi
 AR=$ac_cv_prog_AR
 if test -n "$AR"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AR" >&5
-$as_echo "$AR" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AR" >&5
+printf "%s\n" "$AR" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5961,11 +6738,12 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_AR+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_AR+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_AR"; then
   ac_cv_prog_ac_ct_AR="$ac_ct_AR" # Let the user override the test.
 else
@@ -5973,11 +6751,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_AR="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -5988,11 +6770,11 @@
 fi
 ac_ct_AR=$ac_cv_prog_ac_ct_AR
 if test -n "$ac_ct_AR"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AR" >&5
-$as_echo "$ac_ct_AR" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AR" >&5
+printf "%s\n" "$ac_ct_AR" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6004,8 +6786,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     AR=$ac_ct_AR
@@ -6013,42 +6795,60 @@
 fi
 
 : ${AR=ar}
-: ${AR_FLAGS=cru}
 
 
 
 
 
 
+# Use ARFLAGS variable as AR's operation code to sync the variable naming with
+# Automake.  If both AR_FLAGS and ARFLAGS are specified, AR_FLAGS should have
+# higher priority because thats what people were doing historically (setting
+# ARFLAGS for automake and AR_FLAGS for libtool).  FIXME: Make the AR_FLAGS
+# variable obsoleted/removed.
+
+test ${AR_FLAGS+y} || AR_FLAGS=${ARFLAGS-cr}
+lt_ar_flags=$AR_FLAGS
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for archiver @FILE support" >&5
-$as_echo_n "checking for archiver @FILE support... " >&6; }
-if ${lt_cv_ar_at_file+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+
+# Make AR_FLAGS overridable by 'make ARFLAGS='.  Don't try to run-time override
+# by AR_FLAGS because that was never working and AR_FLAGS is about to die.
+
+
+
+
+
+
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for archiver @FILE support" >&5
+printf %s "checking for archiver @FILE support... " >&6; }
+if test ${lt_cv_ar_at_file+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_ar_at_file=no
    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   echo conftest.$ac_objext > conftest.lst
       lt_ar_try='$AR $AR_FLAGS libconftest.a @conftest.lst >&5'
       { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$lt_ar_try\""; } >&5
   (eval $lt_ar_try) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
       if test 0 -eq "$ac_status"; then
 	# Ensure the archiver fails upon bogus file names.
@@ -6056,7 +6856,7 @@
 	{ { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$lt_ar_try\""; } >&5
   (eval $lt_ar_try) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 	if test 0 -ne "$ac_status"; then
           lt_cv_ar_at_file=@
@@ -6065,11 +6865,11 @@
       rm -f conftest.* libconftest.a
 
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ar_at_file" >&5
-$as_echo "$lt_cv_ar_at_file" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ar_at_file" >&5
+printf "%s\n" "$lt_cv_ar_at_file" >&6; }
 
 if test no = "$lt_cv_ar_at_file"; then
   archiver_list_spec=
@@ -6086,11 +6886,12 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}strip", so it can be a program name with args.
 set dummy ${ac_tool_prefix}strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$STRIP"; then
   ac_cv_prog_STRIP="$STRIP" # Let the user override the test.
 else
@@ -6098,11 +6899,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_STRIP="${ac_tool_prefix}strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -6113,11 +6918,11 @@
 fi
 STRIP=$ac_cv_prog_STRIP
 if test -n "$STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
-$as_echo "$STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
+printf "%s\n" "$STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6126,11 +6931,12 @@
   ac_ct_STRIP=$STRIP
   # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_STRIP"; then
   ac_cv_prog_ac_ct_STRIP="$ac_ct_STRIP" # Let the user override the test.
 else
@@ -6138,11 +6944,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_STRIP="strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -6153,11 +6963,11 @@
 fi
 ac_ct_STRIP=$ac_cv_prog_ac_ct_STRIP
 if test -n "$ac_ct_STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
-$as_echo "$ac_ct_STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
+printf "%s\n" "$ac_ct_STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_STRIP" = x; then
@@ -6165,8 +6975,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     STRIP=$ac_ct_STRIP
@@ -6185,11 +6995,12 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}ranlib", so it can be a program name with args.
 set dummy ${ac_tool_prefix}ranlib; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_RANLIB+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_RANLIB+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$RANLIB"; then
   ac_cv_prog_RANLIB="$RANLIB" # Let the user override the test.
 else
@@ -6197,11 +7008,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_RANLIB="${ac_tool_prefix}ranlib"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -6212,11 +7027,11 @@
 fi
 RANLIB=$ac_cv_prog_RANLIB
 if test -n "$RANLIB"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $RANLIB" >&5
-$as_echo "$RANLIB" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $RANLIB" >&5
+printf "%s\n" "$RANLIB" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6225,11 +7040,12 @@
   ac_ct_RANLIB=$RANLIB
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_RANLIB+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_RANLIB+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_RANLIB"; then
   ac_cv_prog_ac_ct_RANLIB="$ac_ct_RANLIB" # Let the user override the test.
 else
@@ -6237,11 +7053,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_RANLIB="ranlib"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -6252,11 +7072,11 @@
 fi
 ac_ct_RANLIB=$ac_cv_prog_ac_ct_RANLIB
 if test -n "$ac_ct_RANLIB"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_RANLIB" >&5
-$as_echo "$ac_ct_RANLIB" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_RANLIB" >&5
+printf "%s\n" "$ac_ct_RANLIB" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_RANLIB" = x; then
@@ -6264,8 +7084,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     RANLIB=$ac_ct_RANLIB
@@ -6354,11 +7174,12 @@
 
 
 # Check for command to grab the raw symbol name followed by C symbol from nm.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking command to parse $NM output from $compiler object" >&5
-$as_echo_n "checking command to parse $NM output from $compiler object... " >&6; }
-if ${lt_cv_sys_global_symbol_pipe+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking command to parse $NM output from $compiler object" >&5
+printf %s "checking command to parse $NM output from $compiler object... " >&6; }
+if test ${lt_cv_sys_global_symbol_pipe+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
 
 # These are sane defaults that work on at least a few old systems.
 # [They come from Ultrix.  What could be older than Ultrix?!! ;)]
@@ -6413,7 +7234,7 @@
 
 if test "$lt_cv_nm_interface" = "MS dumpbin"; then
   # Gets list of data symbols to import.
-  lt_cv_sys_global_symbol_to_import="sed -n -e 's/^I .* \(.*\)$/\1/p'"
+  lt_cv_sys_global_symbol_to_import="$SED -n -e 's/^I .* \(.*\)$/\1/p'"
   # Adjust the below global symbol transforms to fixup imported variables.
   lt_cdecl_hook=" -e 's/^I .* \(.*\)$/extern __declspec(dllimport) char \1;/p'"
   lt_c_name_hook=" -e 's/^I .* \(.*\)$/  {\"\1\", (void *) 0},/p'"
@@ -6431,20 +7252,20 @@
 # Transform an extracted symbol line into a proper C declaration.
 # Some systems (esp. on ia64) link data and code symbols differently,
 # so use this general approach.
-lt_cv_sys_global_symbol_to_cdecl="sed -n"\
+lt_cv_sys_global_symbol_to_cdecl="$SED -n"\
 $lt_cdecl_hook\
 " -e 's/^T .* \(.*\)$/extern int \1();/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/extern char \1;/p'"
 
 # Transform an extracted symbol line into symbol name and symbol address
-lt_cv_sys_global_symbol_to_c_name_address="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address="$SED -n"\
 $lt_c_name_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/  {\"\1\", (void *) \&\1},/p'"
 
 # Transform an extracted symbol line into symbol name with lib prefix and
 # symbol address.
-lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="$SED -n"\
 $lt_c_name_lib_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(lib.*\)$/  {\"\1\", (void *) \&\1},/p'"\
@@ -6468,7 +7289,7 @@
   if test "$lt_cv_nm_interface" = "MS dumpbin"; then
     # Fake it for dumpbin and say T for any non-static function,
     # D for any global variable and I for any imported variable.
-    # Also find C++ and __fastcall symbols from MSVC++,
+    # Also find C++ and __fastcall symbols from MSVC++ or ICC,
     # which start with @ or ?.
     lt_cv_sys_global_symbol_pipe="$AWK '"\
 "     {last_section=section; section=\$ 3};"\
@@ -6486,9 +7307,9 @@
 "     s[1]~prfx {split(s[1],t,\"@\"); print f,t[1],substr(t[1],length(prfx))}"\
 "     ' prfx=^$ac_symprfx"
   else
-    lt_cv_sys_global_symbol_pipe="sed -n -e 's/^.*[	 ]\($symcode$symcode*\)[	 ][	 ]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
+    lt_cv_sys_global_symbol_pipe="$SED -n -e 's/^.*[	 ]\($symcode$symcode*\)[	 ][	 ]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
   fi
-  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | sed '/ __gnu_lto/d'"
+  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | $SED '/ __gnu_lto/d'"
 
   # Check to see that the pipe works correctly.
   pipe_works=no
@@ -6510,14 +7331,14 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     # Now try to grab the symbols.
     nlist=conftest.nm
     if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$NM conftest.$ac_objext \| "$lt_cv_sys_global_symbol_pipe" \> $nlist\""; } >&5
   (eval $NM conftest.$ac_objext \| "$lt_cv_sys_global_symbol_pipe" \> $nlist) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "$nlist"; then
       # Try sorting and uniquifying the output.
       if sort "$nlist" | uniq > "$nlist"T; then
@@ -6586,7 +7407,7 @@
 	  if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s conftest$ac_exeext; then
 	    pipe_works=yes
 	  fi
@@ -6621,11 +7442,11 @@
   lt_cv_sys_global_symbol_to_cdecl=
 fi
 if test -z "$lt_cv_sys_global_symbol_pipe$lt_cv_sys_global_symbol_to_cdecl"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: failed" >&5
-$as_echo "failed" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: failed" >&5
+printf "%s\n" "failed" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: ok" >&5
-$as_echo "ok" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ok" >&5
+printf "%s\n" "ok" >&6; }
 fi
 
 # Response file support.
@@ -6671,13 +7492,14 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for sysroot" >&5
-$as_echo_n "checking for sysroot... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for sysroot" >&5
+printf %s "checking for sysroot... " >&6; }
 
 # Check whether --with-sysroot was given.
-if test "${with_sysroot+set}" = set; then :
+if test ${with_sysroot+y}
+then :
   withval=$with_sysroot;
-else
+else $as_nop
   with_sysroot=no
 fi
 
@@ -6690,29 +7512,30 @@
    fi
    ;; #(
  /*)
-   lt_sysroot=`echo "$with_sysroot" | sed -e "$sed_quote_subst"`
+   lt_sysroot=`echo "$with_sysroot" | $SED -e "$sed_quote_subst"`
    ;; #(
  no|'')
    ;; #(
  *)
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_sysroot" >&5
-$as_echo "$with_sysroot" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $with_sysroot" >&5
+printf "%s\n" "$with_sysroot" >&6; }
    as_fn_error $? "The sysroot must be an absolute path." "$LINENO" 5
    ;;
 esac
 
- { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${lt_sysroot:-no}" >&5
-$as_echo "${lt_sysroot:-no}" >&6; }
+ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ${lt_sysroot:-no}" >&5
+printf "%s\n" "${lt_sysroot:-no}" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a working dd" >&5
-$as_echo_n "checking for a working dd... " >&6; }
-if ${ac_cv_path_lt_DD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a working dd" >&5
+printf %s "checking for a working dd... " >&6; }
+if test ${ac_cv_path_lt_DD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   printf 0123456789abcdef0123456789abcdef >conftest.i
 cat conftest.i conftest.i >conftest2.i
 : ${lt_DD:=$DD}
@@ -6723,10 +7546,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in dd; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in dd
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_lt_DD="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_lt_DD="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_lt_DD" || continue
 if "$ac_path_lt_DD" bs=32 count=1 <conftest2.i >conftest.out 2>/dev/null; then
   cmp -s conftest.i conftest.out \
@@ -6746,15 +7574,16 @@
 
 rm -f conftest.i conftest2.i conftest.out
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_lt_DD" >&5
-$as_echo "$ac_cv_path_lt_DD" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_lt_DD" >&5
+printf "%s\n" "$ac_cv_path_lt_DD" >&6; }
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to truncate binary pipes" >&5
-$as_echo_n "checking how to truncate binary pipes... " >&6; }
-if ${lt_cv_truncate_bin+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to truncate binary pipes" >&5
+printf %s "checking how to truncate binary pipes... " >&6; }
+if test ${lt_cv_truncate_bin+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   printf 0123456789abcdef0123456789abcdef >conftest.i
 cat conftest.i conftest.i >conftest2.i
 lt_cv_truncate_bin=
@@ -6765,8 +7594,8 @@
 rm -f conftest.i conftest2.i conftest.out
 test -z "$lt_cv_truncate_bin" && lt_cv_truncate_bin="$SED -e 4q"
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_truncate_bin" >&5
-$as_echo "$lt_cv_truncate_bin" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_truncate_bin" >&5
+printf "%s\n" "$lt_cv_truncate_bin" >&6; }
 
 
 
@@ -6789,7 +7618,8 @@
 }
 
 # Check whether --enable-libtool-lock was given.
-if test "${enable_libtool_lock+set}" = set; then :
+if test ${enable_libtool_lock+y}
+then :
   enableval=$enable_libtool_lock;
 fi
 
@@ -6805,9 +7635,9 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *ELF-32*)
 	HPUX_IA64_MODE=32
 	;;
@@ -6825,10 +7655,10 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     if test yes = "$lt_cv_prog_gnu_ld"; then
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -melf32bsmip"
 	  ;;
@@ -6840,7 +7670,7 @@
 	;;
       esac
     else
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -32"
 	  ;;
@@ -6863,10 +7693,10 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     emul=elf
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *32-bit*)
 	emul="${emul}32"
 	;;
@@ -6874,7 +7704,7 @@
 	emul="${emul}64"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *MSB*)
 	emul="${emul}btsmip"
 	;;
@@ -6882,7 +7712,7 @@
 	emul="${emul}ltsmip"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *N32*)
 	emul="${emul}n32"
 	;;
@@ -6904,16 +7734,16 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
       *32-bit*)
 	case $host in
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
 	  x86_64-*linux*)
-	    case `/usr/bin/file conftest.o` in
+	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
 		;;
@@ -6967,11 +7797,12 @@
   # On SCO OpenServer 5, we need -belf to get full-featured binaries.
   SAVE_CFLAGS=$CFLAGS
   CFLAGS="$CFLAGS -belf"
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the C compiler needs -belf" >&5
-$as_echo_n "checking whether the C compiler needs -belf... " >&6; }
-if ${lt_cv_cc_needs_belf+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the C compiler needs -belf" >&5
+printf %s "checking whether the C compiler needs -belf... " >&6; }
+if test ${lt_cv_cc_needs_belf+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
@@ -6982,19 +7813,20 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_cc_needs_belf=yes
-else
+else $as_nop
   lt_cv_cc_needs_belf=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
      ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
@@ -7003,8 +7835,8 @@
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_cc_needs_belf" >&5
-$as_echo "$lt_cv_cc_needs_belf" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_cc_needs_belf" >&5
+printf "%s\n" "$lt_cv_cc_needs_belf" >&6; }
   if test yes != "$lt_cv_cc_needs_belf"; then
     # this is probably gcc 2.8.0, egcs 1.0 or newer; no need for -belf
     CFLAGS=$SAVE_CFLAGS
@@ -7017,9 +7849,9 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
     *64-bit*)
       case $lt_cv_prog_gnu_ld in
       yes*)
@@ -7054,11 +7886,12 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}mt", so it can be a program name with args.
 set dummy ${ac_tool_prefix}mt; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_MANIFEST_TOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_MANIFEST_TOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$MANIFEST_TOOL"; then
   ac_cv_prog_MANIFEST_TOOL="$MANIFEST_TOOL" # Let the user override the test.
 else
@@ -7066,11 +7899,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_MANIFEST_TOOL="${ac_tool_prefix}mt"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7081,11 +7918,11 @@
 fi
 MANIFEST_TOOL=$ac_cv_prog_MANIFEST_TOOL
 if test -n "$MANIFEST_TOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MANIFEST_TOOL" >&5
-$as_echo "$MANIFEST_TOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MANIFEST_TOOL" >&5
+printf "%s\n" "$MANIFEST_TOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7094,11 +7931,12 @@
   ac_ct_MANIFEST_TOOL=$MANIFEST_TOOL
   # Extract the first word of "mt", so it can be a program name with args.
 set dummy mt; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_MANIFEST_TOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_MANIFEST_TOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_MANIFEST_TOOL"; then
   ac_cv_prog_ac_ct_MANIFEST_TOOL="$ac_ct_MANIFEST_TOOL" # Let the user override the test.
 else
@@ -7106,11 +7944,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_MANIFEST_TOOL="mt"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7121,11 +7963,11 @@
 fi
 ac_ct_MANIFEST_TOOL=$ac_cv_prog_ac_ct_MANIFEST_TOOL
 if test -n "$ac_ct_MANIFEST_TOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_MANIFEST_TOOL" >&5
-$as_echo "$ac_ct_MANIFEST_TOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_MANIFEST_TOOL" >&5
+printf "%s\n" "$ac_ct_MANIFEST_TOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_MANIFEST_TOOL" = x; then
@@ -7133,8 +7975,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     MANIFEST_TOOL=$ac_ct_MANIFEST_TOOL
@@ -7144,11 +7986,12 @@
 fi
 
 test -z "$MANIFEST_TOOL" && MANIFEST_TOOL=mt
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $MANIFEST_TOOL is a manifest tool" >&5
-$as_echo_n "checking if $MANIFEST_TOOL is a manifest tool... " >&6; }
-if ${lt_cv_path_mainfest_tool+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $MANIFEST_TOOL is a manifest tool" >&5
+printf %s "checking if $MANIFEST_TOOL is a manifest tool... " >&6; }
+if test ${lt_cv_path_mainfest_tool+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_path_mainfest_tool=no
   echo "$as_me:$LINENO: $MANIFEST_TOOL '-?'" >&5
   $MANIFEST_TOOL '-?' 2>conftest.err > conftest.out
@@ -7158,8 +8001,8 @@
   fi
   rm -f conftest*
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_mainfest_tool" >&5
-$as_echo "$lt_cv_path_mainfest_tool" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_mainfest_tool" >&5
+printf "%s\n" "$lt_cv_path_mainfest_tool" >&6; }
 if test yes != "$lt_cv_path_mainfest_tool"; then
   MANIFEST_TOOL=:
 fi
@@ -7174,11 +8017,12 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dsymutil", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dsymutil; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DSYMUTIL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DSYMUTIL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$DSYMUTIL"; then
   ac_cv_prog_DSYMUTIL="$DSYMUTIL" # Let the user override the test.
 else
@@ -7186,11 +8030,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DSYMUTIL="${ac_tool_prefix}dsymutil"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7201,11 +8049,11 @@
 fi
 DSYMUTIL=$ac_cv_prog_DSYMUTIL
 if test -n "$DSYMUTIL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DSYMUTIL" >&5
-$as_echo "$DSYMUTIL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DSYMUTIL" >&5
+printf "%s\n" "$DSYMUTIL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7214,11 +8062,12 @@
   ac_ct_DSYMUTIL=$DSYMUTIL
   # Extract the first word of "dsymutil", so it can be a program name with args.
 set dummy dsymutil; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DSYMUTIL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DSYMUTIL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_DSYMUTIL"; then
   ac_cv_prog_ac_ct_DSYMUTIL="$ac_ct_DSYMUTIL" # Let the user override the test.
 else
@@ -7226,11 +8075,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DSYMUTIL="dsymutil"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7241,11 +8094,11 @@
 fi
 ac_ct_DSYMUTIL=$ac_cv_prog_ac_ct_DSYMUTIL
 if test -n "$ac_ct_DSYMUTIL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DSYMUTIL" >&5
-$as_echo "$ac_ct_DSYMUTIL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DSYMUTIL" >&5
+printf "%s\n" "$ac_ct_DSYMUTIL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DSYMUTIL" = x; then
@@ -7253,8 +8106,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DSYMUTIL=$ac_ct_DSYMUTIL
@@ -7266,11 +8119,12 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}nmedit", so it can be a program name with args.
 set dummy ${ac_tool_prefix}nmedit; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_NMEDIT+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_NMEDIT+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$NMEDIT"; then
   ac_cv_prog_NMEDIT="$NMEDIT" # Let the user override the test.
 else
@@ -7278,11 +8132,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_NMEDIT="${ac_tool_prefix}nmedit"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7293,11 +8151,11 @@
 fi
 NMEDIT=$ac_cv_prog_NMEDIT
 if test -n "$NMEDIT"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $NMEDIT" >&5
-$as_echo "$NMEDIT" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $NMEDIT" >&5
+printf "%s\n" "$NMEDIT" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7306,11 +8164,12 @@
   ac_ct_NMEDIT=$NMEDIT
   # Extract the first word of "nmedit", so it can be a program name with args.
 set dummy nmedit; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_NMEDIT+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_NMEDIT+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_NMEDIT"; then
   ac_cv_prog_ac_ct_NMEDIT="$ac_ct_NMEDIT" # Let the user override the test.
 else
@@ -7318,11 +8177,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_NMEDIT="nmedit"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7333,11 +8196,11 @@
 fi
 ac_ct_NMEDIT=$ac_cv_prog_ac_ct_NMEDIT
 if test -n "$ac_ct_NMEDIT"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_NMEDIT" >&5
-$as_echo "$ac_ct_NMEDIT" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_NMEDIT" >&5
+printf "%s\n" "$ac_ct_NMEDIT" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_NMEDIT" = x; then
@@ -7345,8 +8208,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     NMEDIT=$ac_ct_NMEDIT
@@ -7358,11 +8221,12 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}lipo", so it can be a program name with args.
 set dummy ${ac_tool_prefix}lipo; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_LIPO+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_LIPO+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$LIPO"; then
   ac_cv_prog_LIPO="$LIPO" # Let the user override the test.
 else
@@ -7370,11 +8234,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_LIPO="${ac_tool_prefix}lipo"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7385,11 +8253,11 @@
 fi
 LIPO=$ac_cv_prog_LIPO
 if test -n "$LIPO"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $LIPO" >&5
-$as_echo "$LIPO" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $LIPO" >&5
+printf "%s\n" "$LIPO" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7398,11 +8266,12 @@
   ac_ct_LIPO=$LIPO
   # Extract the first word of "lipo", so it can be a program name with args.
 set dummy lipo; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_LIPO+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_LIPO+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_LIPO"; then
   ac_cv_prog_ac_ct_LIPO="$ac_ct_LIPO" # Let the user override the test.
 else
@@ -7410,11 +8279,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_LIPO="lipo"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7425,11 +8298,11 @@
 fi
 ac_ct_LIPO=$ac_cv_prog_ac_ct_LIPO
 if test -n "$ac_ct_LIPO"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_LIPO" >&5
-$as_echo "$ac_ct_LIPO" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_LIPO" >&5
+printf "%s\n" "$ac_ct_LIPO" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_LIPO" = x; then
@@ -7437,8 +8310,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     LIPO=$ac_ct_LIPO
@@ -7450,11 +8323,12 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}otool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}otool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$OTOOL"; then
   ac_cv_prog_OTOOL="$OTOOL" # Let the user override the test.
 else
@@ -7462,11 +8336,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OTOOL="${ac_tool_prefix}otool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7477,11 +8355,11 @@
 fi
 OTOOL=$ac_cv_prog_OTOOL
 if test -n "$OTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OTOOL" >&5
-$as_echo "$OTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OTOOL" >&5
+printf "%s\n" "$OTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7490,11 +8368,12 @@
   ac_ct_OTOOL=$OTOOL
   # Extract the first word of "otool", so it can be a program name with args.
 set dummy otool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_OTOOL"; then
   ac_cv_prog_ac_ct_OTOOL="$ac_ct_OTOOL" # Let the user override the test.
 else
@@ -7502,11 +8381,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OTOOL="otool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7517,11 +8400,11 @@
 fi
 ac_ct_OTOOL=$ac_cv_prog_ac_ct_OTOOL
 if test -n "$ac_ct_OTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL" >&5
-$as_echo "$ac_ct_OTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL" >&5
+printf "%s\n" "$ac_ct_OTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OTOOL" = x; then
@@ -7529,8 +8412,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OTOOL=$ac_ct_OTOOL
@@ -7542,11 +8425,12 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}otool64", so it can be a program name with args.
 set dummy ${ac_tool_prefix}otool64; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OTOOL64+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OTOOL64+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$OTOOL64"; then
   ac_cv_prog_OTOOL64="$OTOOL64" # Let the user override the test.
 else
@@ -7554,11 +8438,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OTOOL64="${ac_tool_prefix}otool64"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7569,11 +8457,11 @@
 fi
 OTOOL64=$ac_cv_prog_OTOOL64
 if test -n "$OTOOL64"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OTOOL64" >&5
-$as_echo "$OTOOL64" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OTOOL64" >&5
+printf "%s\n" "$OTOOL64" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7582,11 +8470,12 @@
   ac_ct_OTOOL64=$OTOOL64
   # Extract the first word of "otool64", so it can be a program name with args.
 set dummy otool64; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OTOOL64+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OTOOL64+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_OTOOL64"; then
   ac_cv_prog_ac_ct_OTOOL64="$ac_ct_OTOOL64" # Let the user override the test.
 else
@@ -7594,11 +8483,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OTOOL64="otool64"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -7609,11 +8502,11 @@
 fi
 ac_ct_OTOOL64=$ac_cv_prog_ac_ct_OTOOL64
 if test -n "$ac_ct_OTOOL64"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL64" >&5
-$as_echo "$ac_ct_OTOOL64" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL64" >&5
+printf "%s\n" "$ac_ct_OTOOL64" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OTOOL64" = x; then
@@ -7621,8 +8514,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OTOOL64=$ac_ct_OTOOL64
@@ -7657,11 +8550,12 @@
 
 
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -single_module linker flag" >&5
-$as_echo_n "checking for -single_module linker flag... " >&6; }
-if ${lt_cv_apple_cc_single_mod+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -single_module linker flag" >&5
+printf %s "checking for -single_module linker flag... " >&6; }
+if test ${lt_cv_apple_cc_single_mod+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_apple_cc_single_mod=no
       if test -z "$LT_MULTI_MODULE"; then
 	# By default we will add the -single_module flag. You can override
@@ -7690,14 +8584,15 @@
 	rm -f conftest.*
       fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_apple_cc_single_mod" >&5
-$as_echo "$lt_cv_apple_cc_single_mod" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_apple_cc_single_mod" >&5
+printf "%s\n" "$lt_cv_apple_cc_single_mod" >&6; }
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -exported_symbols_list linker flag" >&5
-$as_echo_n "checking for -exported_symbols_list linker flag... " >&6; }
-if ${lt_cv_ld_exported_symbols_list+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -exported_symbols_list linker flag" >&5
+printf %s "checking for -exported_symbols_list linker flag... " >&6; }
+if test ${lt_cv_ld_exported_symbols_list+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_ld_exported_symbols_list=no
       save_LDFLAGS=$LDFLAGS
       echo "_main" > conftest.sym
@@ -7706,39 +8601,41 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_ld_exported_symbols_list=yes
-else
+else $as_nop
   lt_cv_ld_exported_symbols_list=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 	LDFLAGS=$save_LDFLAGS
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_exported_symbols_list" >&5
-$as_echo "$lt_cv_ld_exported_symbols_list" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_exported_symbols_list" >&5
+printf "%s\n" "$lt_cv_ld_exported_symbols_list" >&6; }
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -force_load linker flag" >&5
-$as_echo_n "checking for -force_load linker flag... " >&6; }
-if ${lt_cv_ld_force_load+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -force_load linker flag" >&5
+printf %s "checking for -force_load linker flag... " >&6; }
+if test ${lt_cv_ld_force_load+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_ld_force_load=no
       cat > conftest.c << _LT_EOF
 int forced_loaded() { return 2;}
 _LT_EOF
       echo "$LTCC $LTCFLAGS -c -o conftest.o conftest.c" >&5
       $LTCC $LTCFLAGS -c -o conftest.o conftest.c 2>&5
-      echo "$AR cru libconftest.a conftest.o" >&5
-      $AR cru libconftest.a conftest.o 2>&5
+      echo "$AR $AR_FLAGS libconftest.a conftest.o" >&5
+      $AR $AR_FLAGS libconftest.a conftest.o 2>&5
       echo "$RANLIB libconftest.a" >&5
       $RANLIB libconftest.a 2>&5
       cat > conftest.c << _LT_EOF
@@ -7758,24 +8655,19 @@
         rm -rf conftest.dSYM
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_force_load" >&5
-$as_echo "$lt_cv_ld_force_load" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_force_load" >&5
+printf "%s\n" "$lt_cv_ld_force_load" >&6; }
     case $host_os in
     rhapsody* | darwin1.[012])
       _lt_dar_allow_undefined='$wl-undefined ${wl}suppress' ;;
     darwin1.*)
       _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-    darwin*) # darwin 5.x on
-      # if running on 10.5 or later, the deployment target defaults
-      # to the OS version, if on x86, and 10.4, the deployment
-      # target defaults to 10.4. Don't you love it?
-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
-	10.0,*86*-darwin8*|10.0,*-darwin[91]*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
-	10.[012][,.]*)
-	  _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-	10.*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+    darwin*)
+      case $MACOSX_DEPLOYMENT_TARGET,$host in
+        10.[012],*|,*powerpc*-darwin[5-8]*)
+          _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+        *)
+          _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
       esac
     ;;
   esac
@@ -7830,148 +8722,42 @@
     esac
 }
 
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
-$as_echo_n "checking for ANSI C header files... " >&6; }
-if ${ac_cv_header_stdc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-int
-main ()
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_header_stdc=yes
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "memchr" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "free" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then :
-  :
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <ctype.h>
-#include <stdlib.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) \
-		   (('a' <= (c) && (c) <= 'i') \
-		     || ('j' <= (c) && (c) <= 'r') \
-		     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-	|| toupper (i) != TOUPPER (i))
-      return 2;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
-$as_echo "$ac_cv_header_stdc" >&6; }
-if test $ac_cv_header_stdc = yes; then
-
-$as_echo "#define STDC_HEADERS 1" >>confdefs.h
-
-fi
-
-# On IRIX 5.3, sys/types and inttypes.h are conflicting.
-for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
-		  inttypes.h stdint.h unistd.h
-do :
-  as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
-ac_fn_c_check_header_compile "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default
-"
-if eval test \"x\$"$as_ac_Header"\" = x"yes"; then :
-  cat >>confdefs.h <<_ACEOF
-#define `$as_echo "HAVE_$ac_header" | $as_tr_cpp` 1
-_ACEOF
-
-fi
-
+ac_header= ac_cache=
+for ac_item in $ac_header_c_list
+do
+  if test $ac_cache; then
+    ac_fn_c_check_header_compile "$LINENO" $ac_header ac_cv_header_$ac_cache "$ac_includes_default"
+    if eval test \"x\$ac_cv_header_$ac_cache\" = xyes; then
+      printf "%s\n" "#define $ac_item 1" >> confdefs.h
+    fi
+    ac_header= ac_cache=
+  elif test $ac_header; then
+    ac_cache=$ac_item
+  else
+    ac_header=$ac_item
+  fi
 done
 
 
-for ac_header in dlfcn.h
-do :
-  ac_fn_c_check_header_compile "$LINENO" "dlfcn.h" "ac_cv_header_dlfcn_h" "$ac_includes_default
-"
-if test "x$ac_cv_header_dlfcn_h" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_DLFCN_H 1
-_ACEOF
+
+
+
+
+
+
+if test $ac_cv_header_stdlib_h = yes && test $ac_cv_header_string_h = yes
+then :
+
+printf "%s\n" "#define STDC_HEADERS 1" >>confdefs.h
 
 fi
+ac_fn_c_check_header_compile "$LINENO" "dlfcn.h" "ac_cv_header_dlfcn_h" "$ac_includes_default
+"
+if test "x$ac_cv_header_dlfcn_h" = xyes
+then :
+  printf "%s\n" "#define HAVE_DLFCN_H 1" >>confdefs.h
 
-done
+fi
 
 
 
@@ -7985,11 +8771,12 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}as", so it can be a program name with args.
 set dummy ${ac_tool_prefix}as; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AS+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AS+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$AS"; then
   ac_cv_prog_AS="$AS" # Let the user override the test.
 else
@@ -7997,11 +8784,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AS="${ac_tool_prefix}as"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8012,11 +8803,11 @@
 fi
 AS=$ac_cv_prog_AS
 if test -n "$AS"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AS" >&5
-$as_echo "$AS" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AS" >&5
+printf "%s\n" "$AS" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8025,11 +8816,12 @@
   ac_ct_AS=$AS
   # Extract the first word of "as", so it can be a program name with args.
 set dummy as; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_AS+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_AS+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_AS"; then
   ac_cv_prog_ac_ct_AS="$ac_ct_AS" # Let the user override the test.
 else
@@ -8037,11 +8829,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_AS="as"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8052,11 +8848,11 @@
 fi
 ac_ct_AS=$ac_cv_prog_ac_ct_AS
 if test -n "$ac_ct_AS"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AS" >&5
-$as_echo "$ac_ct_AS" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AS" >&5
+printf "%s\n" "$ac_ct_AS" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_AS" = x; then
@@ -8064,8 +8860,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     AS=$ac_ct_AS
@@ -8077,11 +8873,12 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dlltool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$DLLTOOL"; then
   ac_cv_prog_DLLTOOL="$DLLTOOL" # Let the user override the test.
 else
@@ -8089,11 +8886,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DLLTOOL="${ac_tool_prefix}dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8104,11 +8905,11 @@
 fi
 DLLTOOL=$ac_cv_prog_DLLTOOL
 if test -n "$DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
-$as_echo "$DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
+printf "%s\n" "$DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8117,11 +8918,12 @@
   ac_ct_DLLTOOL=$DLLTOOL
   # Extract the first word of "dlltool", so it can be a program name with args.
 set dummy dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_DLLTOOL"; then
   ac_cv_prog_ac_ct_DLLTOOL="$ac_ct_DLLTOOL" # Let the user override the test.
 else
@@ -8129,11 +8931,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DLLTOOL="dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8144,11 +8950,11 @@
 fi
 ac_ct_DLLTOOL=$ac_cv_prog_ac_ct_DLLTOOL
 if test -n "$ac_ct_DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
-$as_echo "$ac_ct_DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
+printf "%s\n" "$ac_ct_DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DLLTOOL" = x; then
@@ -8156,8 +8962,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DLLTOOL=$ac_ct_DLLTOOL
@@ -8169,11 +8975,12 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}objdump", so it can be a program name with args.
 set dummy ${ac_tool_prefix}objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$OBJDUMP"; then
   ac_cv_prog_OBJDUMP="$OBJDUMP" # Let the user override the test.
 else
@@ -8181,11 +8988,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OBJDUMP="${ac_tool_prefix}objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8196,11 +9007,11 @@
 fi
 OBJDUMP=$ac_cv_prog_OBJDUMP
 if test -n "$OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
-$as_echo "$OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
+printf "%s\n" "$OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8209,11 +9020,12 @@
   ac_ct_OBJDUMP=$OBJDUMP
   # Extract the first word of "objdump", so it can be a program name with args.
 set dummy objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   if test -n "$ac_ct_OBJDUMP"; then
   ac_cv_prog_ac_ct_OBJDUMP="$ac_ct_OBJDUMP" # Let the user override the test.
 else
@@ -8221,11 +9033,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OBJDUMP="objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -8236,11 +9052,11 @@
 fi
 ac_ct_OBJDUMP=$ac_cv_prog_ac_ct_OBJDUMP
 if test -n "$ac_ct_OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
-$as_echo "$ac_ct_OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
+printf "%s\n" "$ac_ct_OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OBJDUMP" = x; then
@@ -8248,8 +9064,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OBJDUMP=$ac_ct_OBJDUMP
@@ -8286,7 +9102,8 @@
 
 
             # Check whether --enable-shared was given.
-if test "${enable_shared+set}" = set; then :
+if test ${enable_shared+y}
+then :
   enableval=$enable_shared; p=${PACKAGE-default}
     case $enableval in
     yes) enable_shared=yes ;;
@@ -8304,7 +9121,7 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
+else $as_nop
   enable_shared=yes
 fi
 
@@ -8317,7 +9134,8 @@
 
 
   # Check whether --enable-static was given.
-if test "${enable_static+set}" = set; then :
+if test ${enable_static+y}
+then :
   enableval=$enable_static; p=${PACKAGE-default}
     case $enableval in
     yes) enable_static=yes ;;
@@ -8335,7 +9153,7 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
+else $as_nop
   enable_static=yes
 fi
 
@@ -8349,7 +9167,8 @@
 
 
 # Check whether --with-pic was given.
-if test "${with_pic+set}" = set; then :
+if test ${with_pic+y}
+then :
   withval=$with_pic; lt_p=${PACKAGE-default}
     case $withval in
     yes|no) pic_mode=$withval ;;
@@ -8366,7 +9185,7 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
+else $as_nop
   pic_mode=default
 fi
 
@@ -8378,7 +9197,8 @@
 
 
   # Check whether --enable-fast-install was given.
-if test "${enable_fast_install+set}" = set; then :
+if test ${enable_fast_install+y}
+then :
   enableval=$enable_fast_install; p=${PACKAGE-default}
     case $enableval in
     yes) enable_fast_install=yes ;;
@@ -8396,7 +9216,7 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
+else $as_nop
   enable_fast_install=yes
 fi
 
@@ -8410,11 +9230,12 @@
   shared_archive_member_spec=
 case $host,$enable_shared in
 power*-*-aix[5-9]*,yes)
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking which variant of shared library versioning to provide" >&5
-$as_echo_n "checking which variant of shared library versioning to provide... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking which variant of shared library versioning to provide" >&5
+printf %s "checking which variant of shared library versioning to provide... " >&6; }
 
 # Check whether --with-aix-soname was given.
-if test "${with_aix_soname+set}" = set; then :
+if test ${with_aix_soname+y}
+then :
   withval=$with_aix_soname; case $withval in
     aix|svr4|both)
       ;;
@@ -8423,18 +9244,19 @@
       ;;
     esac
     lt_cv_with_aix_soname=$with_aix_soname
-else
-  if ${lt_cv_with_aix_soname+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  if test ${lt_cv_with_aix_soname+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_with_aix_soname=aix
 fi
 
     with_aix_soname=$lt_cv_with_aix_soname
 fi
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_aix_soname" >&5
-$as_echo "$with_aix_soname" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $with_aix_soname" >&5
+printf "%s\n" "$with_aix_soname" >&6; }
   if test aix != "$with_aix_soname"; then
     # For the AIX way of multilib, we name the shared archive member
     # based on the bitwidth used, traditionally 'shr.o' or 'shr_64.o',
@@ -8516,11 +9338,12 @@
    setopt NO_GLOB_SUBST
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for objdir" >&5
-$as_echo_n "checking for objdir... " >&6; }
-if ${lt_cv_objdir+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for objdir" >&5
+printf %s "checking for objdir... " >&6; }
+if test ${lt_cv_objdir+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   rm -f .libs 2>/dev/null
 mkdir .libs 2>/dev/null
 if test -d .libs; then
@@ -8531,17 +9354,15 @@
 fi
 rmdir .libs 2>/dev/null
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_objdir" >&5
-$as_echo "$lt_cv_objdir" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_objdir" >&5
+printf "%s\n" "$lt_cv_objdir" >&6; }
 objdir=$lt_cv_objdir
 
 
 
 
 
-cat >>confdefs.h <<_ACEOF
-#define LT_OBJDIR "$lt_cv_objdir/"
-_ACEOF
+printf "%s\n" "#define LT_OBJDIR \"$lt_cv_objdir/\"" >>confdefs.h
 
 
 
@@ -8562,8 +9383,8 @@
 ofile=libtool
 can_build_shared=yes
 
-# All known linkers require a '.a' archive for static linking (except MSVC,
-# which needs '.lib').
+# All known linkers require a '.a' archive for static linking (except MSVC and
+# ICC, which need '.lib').
 libext=a
 
 with_gnu_ld=$lt_cv_prog_gnu_ld
@@ -8587,11 +9408,12 @@
 case $deplibs_check_method in
 file_magic*)
   if test "$file_magic_cmd" = '$MAGIC_CMD'; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${ac_tool_prefix}file" >&5
-$as_echo_n "checking for ${ac_tool_prefix}file... " >&6; }
-if ${lt_cv_path_MAGIC_CMD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ${ac_tool_prefix}file" >&5
+printf %s "checking for ${ac_tool_prefix}file... " >&6; }
+if test ${lt_cv_path_MAGIC_CMD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   case $MAGIC_CMD in
 [\\/*] |  ?:[\\/]*)
   lt_cv_path_MAGIC_CMD=$MAGIC_CMD # Let the user override the test with a path.
@@ -8640,11 +9462,11 @@
 
 MAGIC_CMD=$lt_cv_path_MAGIC_CMD
 if test -n "$MAGIC_CMD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
-$as_echo "$MAGIC_CMD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
+printf "%s\n" "$MAGIC_CMD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8653,11 +9475,12 @@
 
 if test -z "$lt_cv_path_MAGIC_CMD"; then
   if test -n "$ac_tool_prefix"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for file" >&5
-$as_echo_n "checking for file... " >&6; }
-if ${lt_cv_path_MAGIC_CMD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for file" >&5
+printf %s "checking for file... " >&6; }
+if test ${lt_cv_path_MAGIC_CMD+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   case $MAGIC_CMD in
 [\\/*] |  ?:[\\/]*)
   lt_cv_path_MAGIC_CMD=$MAGIC_CMD # Let the user override the test with a path.
@@ -8706,11 +9529,11 @@
 
 MAGIC_CMD=$lt_cv_path_MAGIC_CMD
 if test -n "$MAGIC_CMD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
-$as_echo "$MAGIC_CMD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
+printf "%s\n" "$MAGIC_CMD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8795,11 +9618,12 @@
     lt_prog_compiler_no_builtin_flag=' -fno-builtin' ;;
   esac
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -fno-rtti -fno-exceptions" >&5
-$as_echo_n "checking if $compiler supports -fno-rtti -fno-exceptions... " >&6; }
-if ${lt_cv_prog_compiler_rtti_exceptions+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -fno-rtti -fno-exceptions" >&5
+printf %s "checking if $compiler supports -fno-rtti -fno-exceptions... " >&6; }
+if test ${lt_cv_prog_compiler_rtti_exceptions+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_rtti_exceptions=no
    ac_outfile=conftest.$ac_objext
    echo "$lt_simple_compile_test_code" > conftest.$ac_ext
@@ -8830,8 +9654,8 @@
    $RM conftest*
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_rtti_exceptions" >&5
-$as_echo "$lt_cv_prog_compiler_rtti_exceptions" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_rtti_exceptions" >&5
+printf "%s\n" "$lt_cv_prog_compiler_rtti_exceptions" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_rtti_exceptions"; then
     lt_prog_compiler_no_builtin_flag="$lt_prog_compiler_no_builtin_flag -fno-rtti -fno-exceptions"
@@ -9072,7 +9896,7 @@
 	lt_prog_compiler_static='-qstaticlink'
 	;;
       *)
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ Ceres\ Fortran* | *Sun*Fortran*\ [1-7].* | *Sun*Fortran*\ 8.[0-3]*)
 	  # Sun Fortran 8.3 passes all unrecognized flags to the linker
 	  lt_prog_compiler_pic='-KPIC'
@@ -9188,26 +10012,28 @@
     ;;
 esac
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $compiler option to produce PIC" >&5
-$as_echo_n "checking for $compiler option to produce PIC... " >&6; }
-if ${lt_cv_prog_compiler_pic+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $compiler option to produce PIC" >&5
+printf %s "checking for $compiler option to produce PIC... " >&6; }
+if test ${lt_cv_prog_compiler_pic+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_pic=$lt_prog_compiler_pic
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic" >&5
-$as_echo "$lt_cv_prog_compiler_pic" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic" >&5
+printf "%s\n" "$lt_cv_prog_compiler_pic" >&6; }
 lt_prog_compiler_pic=$lt_cv_prog_compiler_pic
 
 #
 # Check to make sure the PIC flag actually works.
 #
 if test -n "$lt_prog_compiler_pic"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler PIC flag $lt_prog_compiler_pic works" >&5
-$as_echo_n "checking if $compiler PIC flag $lt_prog_compiler_pic works... " >&6; }
-if ${lt_cv_prog_compiler_pic_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler PIC flag $lt_prog_compiler_pic works" >&5
+printf %s "checking if $compiler PIC flag $lt_prog_compiler_pic works... " >&6; }
+if test ${lt_cv_prog_compiler_pic_works+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_pic_works=no
    ac_outfile=conftest.$ac_objext
    echo "$lt_simple_compile_test_code" > conftest.$ac_ext
@@ -9238,8 +10064,8 @@
    $RM conftest*
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic_works" >&5
-$as_echo "$lt_cv_prog_compiler_pic_works" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic_works" >&5
+printf "%s\n" "$lt_cv_prog_compiler_pic_works" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_pic_works"; then
     case $lt_prog_compiler_pic in
@@ -9267,11 +10093,12 @@
 # Check to make sure the static flag actually works.
 #
 wl=$lt_prog_compiler_wl eval lt_tmp_static_flag=\"$lt_prog_compiler_static\"
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler static flag $lt_tmp_static_flag works" >&5
-$as_echo_n "checking if $compiler static flag $lt_tmp_static_flag works... " >&6; }
-if ${lt_cv_prog_compiler_static_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler static flag $lt_tmp_static_flag works" >&5
+printf %s "checking if $compiler static flag $lt_tmp_static_flag works... " >&6; }
+if test ${lt_cv_prog_compiler_static_works+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_static_works=no
    save_LDFLAGS=$LDFLAGS
    LDFLAGS="$LDFLAGS $lt_tmp_static_flag"
@@ -9295,8 +10122,8 @@
    LDFLAGS=$save_LDFLAGS
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_static_works" >&5
-$as_echo "$lt_cv_prog_compiler_static_works" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_static_works" >&5
+printf "%s\n" "$lt_cv_prog_compiler_static_works" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_static_works"; then
     :
@@ -9310,11 +10137,12 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
-$as_echo_n "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
-if ${lt_cv_prog_compiler_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
+printf %s "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
+if test ${lt_cv_prog_compiler_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_c_o=no
    $RM -r conftest 2>/dev/null
    mkdir conftest
@@ -9357,19 +10185,20 @@
    $RM conftest*
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
-$as_echo "$lt_cv_prog_compiler_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
+printf "%s\n" "$lt_cv_prog_compiler_c_o" >&6; }
 
 
 
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
-$as_echo_n "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
-if ${lt_cv_prog_compiler_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
+printf %s "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
+if test ${lt_cv_prog_compiler_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler_c_o=no
    $RM -r conftest 2>/dev/null
    mkdir conftest
@@ -9412,8 +10241,8 @@
    $RM conftest*
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
-$as_echo "$lt_cv_prog_compiler_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
+printf "%s\n" "$lt_cv_prog_compiler_c_o" >&6; }
 
 
 
@@ -9421,19 +10250,19 @@
 hard_links=nottested
 if test no = "$lt_cv_prog_compiler_c_o" && test no != "$need_locks"; then
   # do not overwrite the value of need_locks provided by the user
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if we can lock with hard links" >&5
-$as_echo_n "checking if we can lock with hard links... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if we can lock with hard links" >&5
+printf %s "checking if we can lock with hard links... " >&6; }
   hard_links=yes
   $RM conftest*
   ln conftest.a conftest.b 2>/dev/null && hard_links=no
   touch conftest.a
   ln conftest.a conftest.b 2>&5 || hard_links=no
   ln conftest.a conftest.b 2>/dev/null && hard_links=no
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $hard_links" >&5
-$as_echo "$hard_links" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $hard_links" >&5
+printf "%s\n" "$hard_links" >&6; }
   if test no = "$hard_links"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&5
-$as_echo "$as_me: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&2;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&5
+printf "%s\n" "$as_me: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&2;}
     need_locks=warn
   fi
 else
@@ -9445,8 +10274,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the $compiler linker ($LD) supports shared libraries" >&5
-$as_echo_n "checking whether the $compiler linker ($LD) supports shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the $compiler linker ($LD) supports shared libraries" >&5
+printf %s "checking whether the $compiler linker ($LD) supports shared libraries... " >&6; }
 
   runpath_var=
   allow_undefined_flag=
@@ -9490,15 +10319,15 @@
 
   case $host_os in
   cygwin* | mingw* | pw32* | cegcc*)
-    # FIXME: the MSVC++ port hasn't been tested in a loooong time
+    # FIXME: the MSVC++ and ICC port hasn't been tested in a loooong time
     # When not using gcc, we currently assume that we are using
-    # Microsoft Visual C++.
+    # Microsoft Visual C++ or Intel C++ Compiler.
     if test yes != "$GCC"; then
       with_gnu_ld=no
     fi
     ;;
   interix*)
-    # we just hope/assume this is gcc and not c89 (= MSVC++)
+    # we just hope/assume this is gcc and not c89 (= MSVC++ or ICC)
     with_gnu_ld=yes
     ;;
   openbsd* | bitrig*)
@@ -9550,7 +10379,7 @@
       whole_archive_flag_spec=
     fi
     supports_anon_versioning=no
-    case `$LD -v | $SED -e 's/(^)\+)\s\+//' 2>&1` in
+    case `$LD -v | $SED -e 's/([^)]\+)\s\+//' 2>&1` in
       *GNU\ gold*) supports_anon_versioning=yes ;;
       *\ [01].* | *\ 2.[0-9].* | *\ 2.10.*) ;; # catch versions < 2.11
       *\ 2.11.93.0.2\ *) supports_anon_versioning=yes ;; # RH7.3 ...
@@ -9662,6 +10491,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       old_archive_From_new_cmds='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       enable_shared_with_static_runtimes=yes
+      file_list_spec='@'
       ;;
 
     interix[3-9]*)
@@ -9676,7 +10506,7 @@
       # 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
       # time.  Moving up from 0x10000000 also allows more sbrk(2) space.
       archive_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-      archive_expsym_cmds='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+      archive_expsym_cmds='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
       ;;
 
     gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu)
@@ -9719,7 +10549,7 @@
 	  compiler_needs_object=yes
 	  ;;
 	esac
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ C*)			# Sun C 5.9
 	  whole_archive_flag_spec='$wl--whole-archive`new_convenience=; for conv in $convenience\"\"; do test -z \"$conv\" || new_convenience=\"$new_convenience,$conv\"; done; func_echo_all \"$new_convenience\"` $wl--no-whole-archive'
 	  compiler_needs_object=yes
@@ -9731,7 +10561,7 @@
 
         if test yes = "$supports_anon_versioning"; then
           archive_expsym_cmds='echo "{ global:" > $output_objdir/$libname.ver~
-            cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+            cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
             echo "local: *; };" >> $output_objdir/$libname.ver~
             $CC '"$tmp_sharedflag""$tmp_addflag"' $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
         fi
@@ -9747,7 +10577,7 @@
 	  archive_cmds='$LD -shared $libobjs $deplibs $linker_flags -soname $soname -o $lib'
 	  if test yes = "$supports_anon_versioning"; then
 	    archive_expsym_cmds='echo "{ global:" > $output_objdir/$libname.ver~
-              cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+              cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
               echo "local: *; };" >> $output_objdir/$libname.ver~
               $LD -shared $libobjs $deplibs $linker_flags -soname $soname -version-script $output_objdir/$libname.ver -o $lib'
 	  fi
@@ -9879,7 +10709,7 @@
 	if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
 	  export_symbols_cmds='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && (substr(\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
 	else
-	  export_symbols_cmds='`func_echo_all $NM | $SED -e '\''s/B\([^B]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && (substr(\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+	  export_symbols_cmds='`func_echo_all $NM | $SED -e '\''s/B\([^B]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && (substr(\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
 	fi
 	aix_use_runtimelinking=no
 
@@ -10001,21 +10831,23 @@
         if test set = "${lt_cv_aix_libpath+set}"; then
   aix_libpath=$lt_cv_aix_libpath
 else
-  if ${lt_cv_aix_libpath_+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  if test ${lt_cv_aix_libpath_+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
 
   lt_aix_libpath_sed='
       /Import File Strings/,/^$/ {
@@ -10030,7 +10862,7 @@
     lt_cv_aix_libpath_=`dump -HX64 conftest$ac_exeext 2>/dev/null | $SED -n -e "$lt_aix_libpath_sed"`
   fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
   if test -z "$lt_cv_aix_libpath_"; then
     lt_cv_aix_libpath_=/usr/lib:/lib
@@ -10054,21 +10886,23 @@
 	 if test set = "${lt_cv_aix_libpath+set}"; then
   aix_libpath=$lt_cv_aix_libpath
 else
-  if ${lt_cv_aix_libpath_+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  if test ${lt_cv_aix_libpath_+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
 
   lt_aix_libpath_sed='
       /Import File Strings/,/^$/ {
@@ -10083,7 +10917,7 @@
     lt_cv_aix_libpath_=`dump -HX64 conftest$ac_exeext 2>/dev/null | $SED -n -e "$lt_aix_libpath_sed"`
   fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
   if test -z "$lt_cv_aix_libpath_"; then
     lt_cv_aix_libpath_=/usr/lib:/lib
@@ -10146,12 +10980,12 @@
 
     cygwin* | mingw* | pw32* | cegcc*)
       # When not using gcc, we currently assume that we are using
-      # Microsoft Visual C++.
+      # Microsoft Visual C++ or Intel C++ Compiler.
       # hardcode_libdir_flag_spec is actually meaningless, as there is
       # no search path for DLLs.
       case $cc_basename in
-      cl*)
-	# Native MSVC
+      cl* | icl*)
+	# Native MSVC or ICC
 	hardcode_libdir_flag_spec=' '
 	allow_undefined_flag=unsupported
 	always_export_symbols=yes
@@ -10192,7 +11026,7 @@
           fi'
 	;;
       *)
-	# Assume MSVC wrapper
+	# Assume MSVC and ICC wrapper
 	hardcode_libdir_flag_spec=' '
 	allow_undefined_flag=unsupported
 	# Tell ltmain to make .lib files, not .a files.
@@ -10233,8 +11067,8 @@
     output_verbose_link_cmd=func_echo_all
     archive_cmds="\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dsymutil"
     module_cmds="\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dsymutil"
-    archive_expsym_cmds="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
-    module_expsym_cmds="sed -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
+    archive_expsym_cmds="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
+    module_expsym_cmds="$SED -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
 
   else
   ld_shlibs=no
@@ -10268,7 +11102,7 @@
       ;;
 
     # FreeBSD 3 and greater uses gcc -shared to do shared libraries.
-    freebsd* | dragonfly*)
+    freebsd* | dragonfly* | midnightbsd*)
       archive_cmds='$CC -shared $pic_flag -o $lib $libobjs $deplibs $compiler_flags'
       hardcode_libdir_flag_spec='-R$libdir'
       hardcode_direct=yes
@@ -10334,11 +11168,12 @@
 
 	  # Older versions of the 11.00 compiler do not understand -b yet
 	  # (HP92453-01 A.11.01.20 doesn't, HP92453-01 B.11.X.35175-35176.GP does)
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $CC understands -b" >&5
-$as_echo_n "checking if $CC understands -b... " >&6; }
-if ${lt_cv_prog_compiler__b+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $CC understands -b" >&5
+printf %s "checking if $CC understands -b... " >&6; }
+if test ${lt_cv_prog_compiler__b+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_prog_compiler__b=no
    save_LDFLAGS=$LDFLAGS
    LDFLAGS="$LDFLAGS -b"
@@ -10362,8 +11197,8 @@
    LDFLAGS=$save_LDFLAGS
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler__b" >&5
-$as_echo "$lt_cv_prog_compiler__b" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler__b" >&5
+printf "%s\n" "$lt_cv_prog_compiler__b" >&6; }
 
 if test yes = "$lt_cv_prog_compiler__b"; then
     archive_cmds='$CC -b $wl+h $wl$soname $wl+b $wl$install_libdir -o $lib $libobjs $deplibs $compiler_flags'
@@ -10403,28 +11238,30 @@
 	# work, assume that -exports_file does not work either and
 	# implicitly export all symbols.
 	# This should be the same for all languages, so no per-tag cache variable.
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the $host_os linker accepts -exported_symbol" >&5
-$as_echo_n "checking whether the $host_os linker accepts -exported_symbol... " >&6; }
-if ${lt_cv_irix_exported_symbol+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the $host_os linker accepts -exported_symbol" >&5
+printf %s "checking whether the $host_os linker accepts -exported_symbol... " >&6; }
+if test ${lt_cv_irix_exported_symbol+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   save_LDFLAGS=$LDFLAGS
 	   LDFLAGS="$LDFLAGS -shared $wl-exported_symbol ${wl}foo $wl-update_registry $wl/dev/null"
 	   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 int foo (void) { return 0; }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_irix_exported_symbol=yes
-else
+else $as_nop
   lt_cv_irix_exported_symbol=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
            LDFLAGS=$save_LDFLAGS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_irix_exported_symbol" >&5
-$as_echo "$lt_cv_irix_exported_symbol" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_irix_exported_symbol" >&5
+printf "%s\n" "$lt_cv_irix_exported_symbol" >&6; }
 	if test yes = "$lt_cv_irix_exported_symbol"; then
           archive_expsym_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-soname $wl$soname `test -n "$verstring" && func_echo_all "$wl-set_version $wl$verstring"` $wl-update_registry $wl$output_objdir/so_locations $wl-exports_file $wl$export_symbols -o $lib'
 	fi
@@ -10516,6 +11353,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       old_archive_From_new_cmds='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       enable_shared_with_static_runtimes=yes
+      file_list_spec='@'
       ;;
 
     osf3*)
@@ -10704,8 +11542,8 @@
     fi
   fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ld_shlibs" >&5
-$as_echo "$ld_shlibs" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ld_shlibs" >&5
+printf "%s\n" "$ld_shlibs" >&6; }
 test no = "$ld_shlibs" && can_build_shared=no
 
 with_gnu_ld=$with_gnu_ld
@@ -10741,18 +11579,19 @@
       # Test whether the compiler implicitly links with -lc since on some
       # systems, -lgcc has to come before -lc. If gcc already passes -lc
       # to ld, don't add -lc before -lgcc.
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -lc should be explicitly linked in" >&5
-$as_echo_n "checking whether -lc should be explicitly linked in... " >&6; }
-if ${lt_cv_archive_cmds_need_lc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether -lc should be explicitly linked in" >&5
+printf %s "checking whether -lc should be explicitly linked in... " >&6; }
+if test ${lt_cv_archive_cmds_need_lc+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   $RM conftest*
 	echo "$lt_simple_compile_test_code" > conftest.$ac_ext
 
 	if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } 2>conftest.err; then
 	  soname=conftest
 	  lib=conftest
@@ -10770,7 +11609,7 @@
 	  if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$archive_cmds 2\>\&1 \| $GREP \" -lc \" \>/dev/null 2\>\&1\""; } >&5
   (eval $archive_cmds 2\>\&1 \| $GREP \" -lc \" \>/dev/null 2\>\&1) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 	  then
 	    lt_cv_archive_cmds_need_lc=no
@@ -10784,8 +11623,8 @@
 	$RM conftest*
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_archive_cmds_need_lc" >&5
-$as_echo "$lt_cv_archive_cmds_need_lc" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_archive_cmds_need_lc" >&5
+printf "%s\n" "$lt_cv_archive_cmds_need_lc" >&6; }
       archive_cmds_need_lc=$lt_cv_archive_cmds_need_lc
       ;;
     esac
@@ -10944,8 +11783,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking dynamic linker characteristics" >&5
-$as_echo_n "checking dynamic linker characteristics... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dynamic linker characteristics" >&5
+printf %s "checking dynamic linker characteristics... " >&6; }
 
 if test yes = "$GCC"; then
   case $host_os in
@@ -11207,7 +12046,7 @@
     case $host_os in
     cygwin*)
       # Cygwin DLLs use 'cyg' prefix rather than 'lib'
-      soname_spec='`echo $libname | sed -e 's/^lib/cyg/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
+      soname_spec='`echo $libname | $SED -e 's/^lib/cyg/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
 
       sys_lib_search_path_spec="$sys_lib_search_path_spec /usr/lib/w32api"
       ;;
@@ -11217,14 +12056,14 @@
       ;;
     pw32*)
       # pw32 DLLs use 'pw' prefix rather than 'lib'
-      library_names_spec='`echo $libname | sed -e 's/^lib/pw/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
+      library_names_spec='`echo $libname | $SED -e 's/^lib/pw/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
       ;;
     esac
     dynamic_linker='Win32 ld.exe'
     ;;
 
-  *,cl*)
-    # Native MSVC
+  *,cl* | *,icl*)
+    # Native MSVC or ICC
     libname_spec='$name'
     soname_spec='$libname`echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
     library_names_spec='$libname.dll.lib'
@@ -11243,7 +12082,7 @@
       done
       IFS=$lt_save_ifs
       # Convert to MSYS style.
-      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | sed -e 's|\\\\|/|g' -e 's| \\([a-zA-Z]\\):| /\\1|g' -e 's|^ ||'`
+      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | $SED -e 's|\\\\|/|g' -e 's| \\([a-zA-Z]\\):| /\\1|g' -e 's|^ ||'`
       ;;
     cygwin*)
       # Convert to unix form, then to dos form, then back to unix form
@@ -11280,7 +12119,7 @@
     ;;
 
   *)
-    # Assume MSVC wrapper
+    # Assume MSVC and ICC wrapper
     library_names_spec='$libname`echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext $libname.lib'
     dynamic_linker='Win32 ld.exe'
     ;;
@@ -11313,7 +12152,7 @@
   shlibpath_var=LD_LIBRARY_PATH
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   # DragonFly does not have aout.  When/if they implement a new
   # versioning mechanism, adjust this.
   if test -x /usr/bin/objformat; then
@@ -11506,9 +12345,10 @@
   shlibpath_overrides_runpath=no
 
   # Some binutils ld are patched to set DT_RUNPATH
-  if ${lt_cv_shlibpath_overrides_runpath+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+  if test ${lt_cv_shlibpath_overrides_runpath+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   lt_cv_shlibpath_overrides_runpath=no
     save_LDFLAGS=$LDFLAGS
     save_libdir=$libdir
@@ -11518,19 +12358,21 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  if  ($OBJDUMP -p conftest$ac_exeext) 2>/dev/null | grep "RUNPATH.*$libdir" >/dev/null; then :
+if ac_fn_c_try_link "$LINENO"
+then :
+  if  ($OBJDUMP -p conftest$ac_exeext) 2>/dev/null | grep "RUNPATH.*$libdir" >/dev/null
+then :
   lt_cv_shlibpath_overrides_runpath=yes
 fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
     LDFLAGS=$save_LDFLAGS
     libdir=$save_libdir
@@ -11762,8 +12604,8 @@
   dynamic_linker=no
   ;;
 esac
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $dynamic_linker" >&5
-$as_echo "$dynamic_linker" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $dynamic_linker" >&5
+printf "%s\n" "$dynamic_linker" >&6; }
 test no = "$dynamic_linker" && can_build_shared=no
 
 variables_saved_for_relink="PATH $shlibpath_var $runpath_var"
@@ -11884,8 +12726,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking how to hardcode library paths into programs" >&5
-$as_echo_n "checking how to hardcode library paths into programs... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to hardcode library paths into programs" >&5
+printf %s "checking how to hardcode library paths into programs... " >&6; }
 hardcode_action=
 if test -n "$hardcode_libdir_flag_spec" ||
    test -n "$runpath_var" ||
@@ -11909,8 +12751,8 @@
   # directories.
   hardcode_action=unsupported
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $hardcode_action" >&5
-$as_echo "$hardcode_action" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $hardcode_action" >&5
+printf "%s\n" "$hardcode_action" >&6; }
 
 if test relink = "$hardcode_action" ||
    test yes = "$inherit_rpath"; then
@@ -11954,11 +12796,12 @@
 
   darwin*)
     # if libdl is installed we need to link against it
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
-$as_echo_n "checking for dlopen in -ldl... " >&6; }
-if ${ac_cv_lib_dl_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
+printf %s "checking for dlopen in -ldl... " >&6; }
+if test ${ac_cv_lib_dl_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldl  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -11967,32 +12810,31 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char dlopen ();
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dl_dlopen=yes
-else
+else $as_nop
   ac_cv_lib_dl_dlopen=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
-$as_echo "$ac_cv_lib_dl_dlopen" >&6; }
-if test "x$ac_cv_lib_dl_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_dl_dlopen" >&6; }
+if test "x$ac_cv_lib_dl_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-ldl
-else
+else $as_nop
 
     lt_cv_dlopen=dyld
     lt_cv_dlopen_libs=
@@ -12012,14 +12854,16 @@
 
   *)
     ac_fn_c_check_func "$LINENO" "shl_load" "ac_cv_func_shl_load"
-if test "x$ac_cv_func_shl_load" = xyes; then :
+if test "x$ac_cv_func_shl_load" = xyes
+then :
   lt_cv_dlopen=shl_load
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for shl_load in -ldld" >&5
-$as_echo_n "checking for shl_load in -ldld... " >&6; }
-if ${ac_cv_lib_dld_shl_load+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for shl_load in -ldld" >&5
+printf %s "checking for shl_load in -ldld... " >&6; }
+if test ${ac_cv_lib_dld_shl_load+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -12028,41 +12872,42 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char shl_load ();
 int
-main ()
+main (void)
 {
 return shl_load ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dld_shl_load=yes
-else
+else $as_nop
   ac_cv_lib_dld_shl_load=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_shl_load" >&5
-$as_echo "$ac_cv_lib_dld_shl_load" >&6; }
-if test "x$ac_cv_lib_dld_shl_load" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_shl_load" >&5
+printf "%s\n" "$ac_cv_lib_dld_shl_load" >&6; }
+if test "x$ac_cv_lib_dld_shl_load" = xyes
+then :
   lt_cv_dlopen=shl_load lt_cv_dlopen_libs=-ldld
-else
+else $as_nop
   ac_fn_c_check_func "$LINENO" "dlopen" "ac_cv_func_dlopen"
-if test "x$ac_cv_func_dlopen" = xyes; then :
+if test "x$ac_cv_func_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
-$as_echo_n "checking for dlopen in -ldl... " >&6; }
-if ${ac_cv_lib_dl_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
+printf %s "checking for dlopen in -ldl... " >&6; }
+if test ${ac_cv_lib_dl_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldl  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -12071,37 +12916,37 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char dlopen ();
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dl_dlopen=yes
-else
+else $as_nop
   ac_cv_lib_dl_dlopen=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
-$as_echo "$ac_cv_lib_dl_dlopen" >&6; }
-if test "x$ac_cv_lib_dl_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_dl_dlopen" >&6; }
+if test "x$ac_cv_lib_dl_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-ldl
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -lsvld" >&5
-$as_echo_n "checking for dlopen in -lsvld... " >&6; }
-if ${ac_cv_lib_svld_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -lsvld" >&5
+printf %s "checking for dlopen in -lsvld... " >&6; }
+if test ${ac_cv_lib_svld_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-lsvld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -12110,37 +12955,37 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char dlopen ();
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_svld_dlopen=yes
-else
+else $as_nop
   ac_cv_lib_svld_dlopen=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_svld_dlopen" >&5
-$as_echo "$ac_cv_lib_svld_dlopen" >&6; }
-if test "x$ac_cv_lib_svld_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_svld_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_svld_dlopen" >&6; }
+if test "x$ac_cv_lib_svld_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-lsvld
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dld_link in -ldld" >&5
-$as_echo_n "checking for dld_link in -ldld... " >&6; }
-if ${ac_cv_lib_dld_dld_link+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dld_link in -ldld" >&5
+printf %s "checking for dld_link in -ldld... " >&6; }
+if test ${ac_cv_lib_dld_dld_link+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -12149,30 +12994,29 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char dld_link ();
 int
-main ()
+main (void)
 {
 return dld_link ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dld_dld_link=yes
-else
+else $as_nop
   ac_cv_lib_dld_dld_link=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_dld_link" >&5
-$as_echo "$ac_cv_lib_dld_dld_link" >&6; }
-if test "x$ac_cv_lib_dld_dld_link" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_dld_link" >&5
+printf "%s\n" "$ac_cv_lib_dld_dld_link" >&6; }
+if test "x$ac_cv_lib_dld_dld_link" = xyes
+then :
   lt_cv_dlopen=dld_link lt_cv_dlopen_libs=-ldld
 fi
 
@@ -12211,11 +13055,12 @@
     save_LIBS=$LIBS
     LIBS="$lt_cv_dlopen_libs $LIBS"
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether a program can dlopen itself" >&5
-$as_echo_n "checking whether a program can dlopen itself... " >&6; }
-if ${lt_cv_dlopen_self+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether a program can dlopen itself" >&5
+printf %s "checking whether a program can dlopen itself... " >&6; }
+if test ${lt_cv_dlopen_self+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   	  if test yes = "$cross_compiling"; then :
   lt_cv_dlopen_self=cross
 else
@@ -12294,7 +13139,7 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "conftest$ac_exeext" 2>/dev/null; then
     (./conftest; exit; ) >&5 2>/dev/null
     lt_status=$?
@@ -12312,16 +13157,17 @@
 
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self" >&5
-$as_echo "$lt_cv_dlopen_self" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self" >&5
+printf "%s\n" "$lt_cv_dlopen_self" >&6; }
 
     if test yes = "$lt_cv_dlopen_self"; then
       wl=$lt_prog_compiler_wl eval LDFLAGS=\"\$LDFLAGS $lt_prog_compiler_static\"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether a statically linked program can dlopen itself" >&5
-$as_echo_n "checking whether a statically linked program can dlopen itself... " >&6; }
-if ${lt_cv_dlopen_self_static+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether a statically linked program can dlopen itself" >&5
+printf %s "checking whether a statically linked program can dlopen itself... " >&6; }
+if test ${lt_cv_dlopen_self_static+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   	  if test yes = "$cross_compiling"; then :
   lt_cv_dlopen_self_static=cross
 else
@@ -12400,7 +13246,7 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "conftest$ac_exeext" 2>/dev/null; then
     (./conftest; exit; ) >&5 2>/dev/null
     lt_status=$?
@@ -12418,8 +13264,8 @@
 
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self_static" >&5
-$as_echo "$lt_cv_dlopen_self_static" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self_static" >&5
+printf "%s\n" "$lt_cv_dlopen_self_static" >&6; }
     fi
 
     CPPFLAGS=$save_CPPFLAGS
@@ -12457,32 +13303,43 @@
 
 striplib=
 old_striplib=
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether stripping libraries is possible" >&5
-$as_echo_n "checking whether stripping libraries is possible... " >&6; }
-if test -n "$STRIP" && $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
-  test -z "$old_striplib" && old_striplib="$STRIP --strip-debug"
-  test -z "$striplib" && striplib="$STRIP --strip-unneeded"
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether stripping libraries is possible" >&5
+printf %s "checking whether stripping libraries is possible... " >&6; }
+if test -z "$STRIP"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 else
-# FIXME - insert some real tests, host_os isn't really good enough
-  case $host_os in
-  darwin*)
-    if test -n "$STRIP"; then
+  if $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
+    old_striplib="$STRIP --strip-debug"
+    striplib="$STRIP --strip-unneeded"
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+  else
+    case $host_os in
+    darwin*)
+      # FIXME - insert some real tests, host_os isn't really good enough
       striplib="$STRIP -x"
       old_striplib="$STRIP -S"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-    else
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    fi
-    ;;
-  *)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    ;;
-  esac
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+      ;;
+    freebsd*)
+      if $STRIP -V 2>&1 | $GREP "elftoolchain" >/dev/null; then
+        old_striplib="$STRIP --strip-debug"
+        striplib="$STRIP --strip-unneeded"
+        { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+      else
+        { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+      fi
+      ;;
+    *)
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+      ;;
+    esac
+  fi
 fi
 
 
@@ -12497,13 +13354,13 @@
 
 
   # Report what library types will actually be built
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if libtool supports shared libraries" >&5
-$as_echo_n "checking if libtool supports shared libraries... " >&6; }
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $can_build_shared" >&5
-$as_echo "$can_build_shared" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if libtool supports shared libraries" >&5
+printf %s "checking if libtool supports shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $can_build_shared" >&5
+printf "%s\n" "$can_build_shared" >&6; }
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to build shared libraries" >&5
-$as_echo_n "checking whether to build shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to build shared libraries" >&5
+printf %s "checking whether to build shared libraries... " >&6; }
   test no = "$can_build_shared" && enable_shared=no
 
   # On AIX, shared libraries and static libraries use the same namespace, and
@@ -12527,15 +13384,15 @@
     fi
     ;;
   esac
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_shared" >&5
-$as_echo "$enable_shared" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $enable_shared" >&5
+printf "%s\n" "$enable_shared" >&6; }
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to build static libraries" >&5
-$as_echo_n "checking whether to build static libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to build static libraries" >&5
+printf %s "checking whether to build static libraries... " >&6; }
   # Make sure either enable_shared or enable_static is yes.
   test yes = "$enable_shared" || enable_static=yes
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_static" >&5
-$as_echo "$enable_static" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $enable_static" >&5
+printf "%s\n" "$enable_static" >&6; }
 
 
 
@@ -12575,17 +13432,17 @@
 
 # Some awks crash when confronted with pnglibconf.dfa, do a test run now
 # to make sure this doesn't happen
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking that AWK works" >&5
-$as_echo_n "checking that AWK works... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking that AWK works" >&5
+printf %s "checking that AWK works... " >&6; }
 if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
    ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
    ${srcdir}/pngusr.dfa 1>&2
 then
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: ok" >&5
-$as_echo "ok" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ok" >&5
+printf "%s\n" "ok" >&6; }
 else
-   { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+   { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error 1 "failed
 See \`config.log' for more details" "$LINENO" 5; }
 fi
@@ -12595,18 +13452,19 @@
 DFNCPP="$CPP"
 
 
-# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
-# checks the compiler with a program that generates a warning), add the
-# following option to deal with this
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail
+# (it checks the compiler with a program that generates a warning).
+# Add the following option to deal with this:
 
 # Check whether --enable-werror was given.
-if test "${enable_werror+set}" = set; then :
+if test ${enable_werror+y}
+then :
   enableval=$enable_werror; test "$enable_werror" = "yes" && enable_werror="-Werror"
     if test "$enable_werror" != "no"; then
       sav_CFLAGS="$CFLAGS"
       CFLAGS="$enable_werror $CFLAGS"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking if the compiler allows $enable_werror" >&5
-$as_echo_n "checking if the compiler allows $enable_werror... " >&6; }
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if the compiler allows $enable_werror" >&5
+printf %s "checking if the compiler allows $enable_werror... " >&6; }
       cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -12614,26 +13472,27 @@
             return argv[argc-1][0];
             }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+if ac_fn_c_try_compile "$LINENO"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
          PNG_COPTS="$PNG_COPTS $enable_werror"
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
       CFLAGS="$sav_CFLAGS"
     fi
 fi
 
 
-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the
-# "-std=c89" compiler option:
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if we need to force back C standard to C89" >&5
-$as_echo_n "checking if we need to force back C standard to C89... " >&6; }
+# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89.
+# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining
+# _POSIX_SOURCE to 1. This is incompatible with the new default mode, so
+# we test for that and force the "-std=c89" compiler option:
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if we need to force back C standard to C89" >&5
+printf %s "checking if we need to force back C standard to C89... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -12641,247 +13500,43 @@
       #include <stdio.h>
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-else
+if ac_fn_c_try_compile "$LINENO"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+else $as_nop
 
       if test "x$GCC" != "xyes"; then
          as_fn_error $? "Forcing back to C89 is required but the flags are only known for GCC" "$LINENO" 5
       fi
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
    CFLAGS="$CFLAGS -std=c89"
 
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 
-# Checks for header files.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
-$as_echo_n "checking for ANSI C header files... " >&6; }
-if ${ac_cv_header_stdc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-int
-main ()
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_header_stdc=yes
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "memchr" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "free" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then :
-  :
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <ctype.h>
-#include <stdlib.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) \
-		   (('a' <= (c) && (c) <= 'i') \
-		     || ('j' <= (c) && (c) <= 'r') \
-		     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-	|| toupper (i) != TOUPPER (i))
-      return 2;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
-$as_echo "$ac_cv_header_stdc" >&6; }
-if test $ac_cv_header_stdc = yes; then
-
-$as_echo "#define STDC_HEADERS 1" >>confdefs.h
-
-fi
-
-
-# Checks for typedefs, structures, and compiler characteristics.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for an ANSI C-conforming const" >&5
-$as_echo_n "checking for an ANSI C-conforming const... " >&6; }
-if ${ac_cv_c_const+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-int
-main ()
-{
-
-#ifndef __cplusplus
-  /* Ultrix mips cc rejects this sort of thing.  */
-  typedef int charset[2];
-  const charset cs = { 0, 0 };
-  /* SunOS 4.1.1 cc rejects this.  */
-  char const *const *pcpcc;
-  char **ppc;
-  /* NEC SVR4.0.2 mips cc rejects this.  */
-  struct point {int x, y;};
-  static struct point const zero = {0,0};
-  /* AIX XL C 1.02.0.0 rejects this.
-     It does not let you subtract one const X* pointer from another in
-     an arm of an if-expression whose if-part is not a constant
-     expression */
-  const char *g = "string";
-  pcpcc = &g + (g ? g-g : 0);
-  /* HPUX 7.0 cc rejects these. */
-  ++pcpcc;
-  ppc = (char**) pcpcc;
-  pcpcc = (char const *const *) ppc;
-  { /* SCO 3.2v4 cc rejects this sort of thing.  */
-    char tx;
-    char *t = &tx;
-    char const *s = 0 ? (char *) 0 : (char const *) 0;
-
-    *t++ = 0;
-    if (s) return 0;
-  }
-  { /* Someone thinks the Sun supposedly-ANSI compiler will reject this.  */
-    int x[] = {25, 17};
-    const int *foo = &x[0];
-    ++foo;
-  }
-  { /* Sun SC1.0 ANSI compiler rejects this -- but not the above. */
-    typedef const int *iptr;
-    iptr p = 0;
-    ++p;
-  }
-  { /* AIX XL C 1.02.0.0 rejects this sort of thing, saying
-       "k.c", line 2.27: 1506-025 (S) Operand must be a modifiable lvalue. */
-    struct s { int j; const int *ap[3]; } bx;
-    struct s *b = &bx; b->j = 5;
-  }
-  { /* ULTRIX-32 V3.1 (Rev 9) vcc rejects this */
-    const int foo = 10;
-    if (!foo) return 0;
-  }
-  return !cs[0] && !zero.x;
-#endif
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_c_const=yes
-else
-  ac_cv_c_const=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_const" >&5
-$as_echo "$ac_cv_c_const" >&6; }
-if test $ac_cv_c_const = no; then
-
-$as_echo "#define const /**/" >>confdefs.h
-
-fi
-
-ac_fn_c_check_type "$LINENO" "size_t" "ac_cv_type_size_t" "$ac_includes_default"
-if test "x$ac_cv_type_size_t" = xyes; then :
-
-else
-
-cat >>confdefs.h <<_ACEOF
-#define size_t unsigned int
-_ACEOF
-
-fi
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether struct tm is in sys/time.h or time.h" >&5
-$as_echo_n "checking whether struct tm is in sys/time.h or time.h... " >&6; }
-if ${ac_cv_struct_tm+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+# Checks for structures and compiler characteristics.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether struct tm is in sys/time.h or time.h" >&5
+printf %s "checking whether struct tm is in sys/time.h or time.h... " >&6; }
+if test ${ac_cv_struct_tm+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 #include <sys/types.h>
 #include <time.h>
 
 int
-main ()
+main (void)
 {
 struct tm tm;
 				     int *p = &tm.tm_sec;
@@ -12890,196 +13545,89 @@
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_struct_tm=time.h
-else
+else $as_nop
   ac_cv_struct_tm=sys/time.h
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_struct_tm" >&5
-$as_echo "$ac_cv_struct_tm" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_struct_tm" >&5
+printf "%s\n" "$ac_cv_struct_tm" >&6; }
 if test $ac_cv_struct_tm = sys/time.h; then
 
-$as_echo "#define TM_IN_SYS_TIME 1" >>confdefs.h
+printf "%s\n" "#define TM_IN_SYS_TIME 1" >>confdefs.h
 
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5
-$as_echo_n "checking for C/C++ restrict keyword... " >&6; }
-if ${ac_cv_c_restrict+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5
+printf %s "checking for C/C++ restrict keyword... " >&6; }
+if test ${ac_cv_c_restrict+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_cv_c_restrict=no
-   # The order here caters to the fact that C++ does not require restrict.
-   for ac_kw in __restrict __restrict__ _Restrict restrict; do
+   # Put '__restrict__' first, to avoid problems with glibc and non-GCC; see:
+   # https://lists.gnu.org/archive/html/bug-autoconf/2016-02/msg00006.html
+   # Put 'restrict' last, because C++ lacks it.
+   for ac_kw in __restrict__ __restrict _Restrict restrict; do
      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-typedef int * int_ptr;
-	int foo (int_ptr $ac_kw ip) {
-	return ip[0];
-       }
+typedef int *int_ptr;
+	   int foo (int_ptr $ac_kw ip) { return ip[0]; }
+	   int bar (int [$ac_kw]); /* Catch GCC bug 14050.  */
+	   int bar (int ip[$ac_kw]) { return ip[0]; }
+
 int
-main ()
+main (void)
 {
 int s[1];
-	int * $ac_kw t = s;
-	t[0] = 0;
-	return foo(t)
+	   int *$ac_kw t = s;
+	   t[0] = 0;
+	   return foo (t) + bar (t);
+
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_c_restrict=$ac_kw
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
      test "$ac_cv_c_restrict" != no && break
    done
 
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_restrict" >&5
-$as_echo "$ac_cv_c_restrict" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_restrict" >&5
+printf "%s\n" "$ac_cv_c_restrict" >&6; }
 
  case $ac_cv_c_restrict in
    restrict) ;;
-   no) $as_echo "#define restrict /**/" >>confdefs.h
+   no) printf "%s\n" "#define restrict /**/" >>confdefs.h
  ;;
-   *)  cat >>confdefs.h <<_ACEOF
-#define restrict $ac_cv_c_restrict
-_ACEOF
+   *)  printf "%s\n" "#define restrict $ac_cv_c_restrict" >>confdefs.h
  ;;
  esac
 
 
 # Checks for library functions.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for working strtod" >&5
-$as_echo_n "checking for working strtod... " >&6; }
-if ${ac_cv_func_strtod+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test "$cross_compiling" = yes; then :
-  ac_cv_func_strtod=no
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
 
-$ac_includes_default
-#ifndef strtod
-double strtod ();
-#endif
-int
-main()
-{
-  {
-    /* Some versions of Linux strtod mis-parse strings with leading '+'.  */
-    char *string = " +69";
-    char *term;
-    double value;
-    value = strtod (string, &term);
-    if (value != 69 || term != (string + 4))
-      return 1;
-  }
-
-  {
-    /* Under Solaris 2.4, strtod returns the wrong value for the
-       terminating character under some conditions.  */
-    char *string = "NaN";
-    char *term;
-    strtod (string, &term);
-    if (term != string && *(term - 1) == 0)
-      return 1;
-  }
-  return 0;
-}
-
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-  ac_cv_func_strtod=yes
-else
-  ac_cv_func_strtod=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_func_strtod" >&5
-$as_echo "$ac_cv_func_strtod" >&6; }
-if test $ac_cv_func_strtod = no; then
-  case " $LIBOBJS " in
-  *" strtod.$ac_objext "* ) ;;
-  *) LIBOBJS="$LIBOBJS strtod.$ac_objext"
- ;;
-esac
-
-ac_fn_c_check_func "$LINENO" "pow" "ac_cv_func_pow"
-if test "x$ac_cv_func_pow" = xyes; then :
-
-fi
-
-if test $ac_cv_func_pow = no; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
-$as_echo_n "checking for pow in -lm... " >&6; }
-if ${ac_cv_lib_m_pow+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
-LIBS="-lm  $LIBS"
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-/* Override any GCC internal prototype to avoid an error.
-   Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
-char pow ();
-int
-main ()
-{
-return pow ();
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  ac_cv_lib_m_pow=yes
-else
-  ac_cv_lib_m_pow=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
-$as_echo "$ac_cv_lib_m_pow" >&6; }
-if test "x$ac_cv_lib_m_pow" = xyes; then :
-  POW_LIB=-lm
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cannot find library containing definition of pow" >&5
-$as_echo "$as_me: WARNING: cannot find library containing definition of pow" >&2;}
-fi
-
-fi
-
-fi
-
-for ac_func in pow
+  for ac_func in pow
 do :
   ac_fn_c_check_func "$LINENO" "pow" "ac_cv_func_pow"
-if test "x$ac_cv_func_pow" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_POW 1
-_ACEOF
+if test "x$ac_cv_func_pow" = xyes
+then :
+  printf "%s\n" "#define HAVE_POW 1" >>confdefs.h
 
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
-$as_echo_n "checking for pow in -lm... " >&6; }
-if ${ac_cv_lib_m_pow+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
+printf %s "checking for pow in -lm... " >&6; }
+if test ${ac_cv_lib_m_pow+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-lm  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -13088,52 +13636,50 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char pow ();
 int
-main ()
+main (void)
 {
 return pow ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_m_pow=yes
-else
+else $as_nop
   ac_cv_lib_m_pow=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
-$as_echo "$ac_cv_lib_m_pow" >&6; }
-if test "x$ac_cv_lib_m_pow" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBM 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
+printf "%s\n" "$ac_cv_lib_m_pow" >&6; }
+if test "x$ac_cv_lib_m_pow" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBM 1" >>confdefs.h
 
   LIBS="-lm $LIBS"
 
-else
+else $as_nop
   as_fn_error $? "cannot find pow" "$LINENO" 5
 fi
 
 fi
+
 done
 
-
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
+# Some later POSIX 1003.1 functions are required for test programs, failure
+# here is soft (the corresponding test program is not built).
 ac_fn_c_check_func "$LINENO" "clock_gettime" "ac_cv_func_clock_gettime"
-if test "x$ac_cv_func_clock_gettime" = xyes; then :
+if test "x$ac_cv_func_clock_gettime" = xyes
+then :
 
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: not building timepng" >&5
-$as_echo "$as_me: WARNING: not building timepng" >&2;}
+else $as_nop
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: not building timepng" >&5
+printf "%s\n" "$as_me: WARNING: not building timepng" >&2;}
 fi
 
  if test "$ac_cv_func_clock_gettime" = "yes"; then
@@ -13147,17 +13693,19 @@
 
 
 # Check whether --with-zlib-prefix was given.
-if test "${with_zlib_prefix+set}" = set; then :
+if test ${with_zlib_prefix+y}
+then :
   withval=$with_zlib_prefix; ZPREFIX=${withval}
-else
+else $as_nop
   ZPREFIX='z_'
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for zlibVersion in -lz" >&5
-$as_echo_n "checking for zlibVersion in -lz... " >&6; }
-if ${ac_cv_lib_z_zlibVersion+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for zlibVersion in -lz" >&5
+printf %s "checking for zlibVersion in -lz... " >&6; }
+if test ${ac_cv_lib_z_zlibVersion+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-lz  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -13166,43 +13714,41 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char zlibVersion ();
 int
-main ()
+main (void)
 {
 return zlibVersion ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_z_zlibVersion=yes
-else
+else $as_nop
   ac_cv_lib_z_zlibVersion=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_z_zlibVersion" >&5
-$as_echo "$ac_cv_lib_z_zlibVersion" >&6; }
-if test "x$ac_cv_lib_z_zlibVersion" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBZ 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_z_zlibVersion" >&5
+printf "%s\n" "$ac_cv_lib_z_zlibVersion" >&6; }
+if test "x$ac_cv_lib_z_zlibVersion" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBZ 1" >>confdefs.h
 
   LIBS="-lz $LIBS"
 
-else
-  as_ac_Lib=`$as_echo "ac_cv_lib_z_${ZPREFIX}zlibVersion" | $as_tr_sh`
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${ZPREFIX}zlibVersion in -lz" >&5
-$as_echo_n "checking for ${ZPREFIX}zlibVersion in -lz... " >&6; }
-if eval \${$as_ac_Lib+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+else $as_nop
+  as_ac_Lib=`printf "%s\n" "ac_cv_lib_z_${ZPREFIX}zlibVersion" | $as_tr_sh`
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ${ZPREFIX}zlibVersion in -lz" >&5
+printf %s "checking for ${ZPREFIX}zlibVersion in -lz... " >&6; }
+if eval test \${$as_ac_Lib+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-lz  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -13211,38 +13757,35 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char ${ZPREFIX}zlibVersion ();
 int
-main ()
+main (void)
 {
 return ${ZPREFIX}zlibVersion ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   eval "$as_ac_Lib=yes"
-else
+else $as_nop
   eval "$as_ac_Lib=no"
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
 eval ac_res=\$$as_ac_Lib
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBZ 1
-_ACEOF
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
+if eval test \"x\$"$as_ac_Lib"\" = x"yes"
+then :
+  printf "%s\n" "#define HAVE_LIBZ 1" >>confdefs.h
 
   LIBS="-lz $LIBS"
 
-else
+else $as_nop
   as_fn_error $? "zlib not installed" "$LINENO" 5
 fi
 
@@ -13252,11 +13795,12 @@
 # The following is for pngvalid, to ensure it catches FP errors even on
 # platforms that don't enable FP exceptions, the function appears in the math
 # library (typically), it's not an error if it is not found.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for feenableexcept in -lm" >&5
-$as_echo_n "checking for feenableexcept in -lm... " >&6; }
-if ${ac_cv_lib_m_feenableexcept+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for feenableexcept in -lm" >&5
+printf %s "checking for feenableexcept in -lm... " >&6; }
+if test ${ac_cv_lib_m_feenableexcept+y}
+then :
+  printf %s "(cached) " >&6
+else $as_nop
   ac_check_lib_save_LIBS=$LIBS
 LIBS="-lm  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
@@ -13265,61 +13809,54 @@
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
    builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
 char feenableexcept ();
 int
-main ()
+main (void)
 {
 return feenableexcept ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_m_feenableexcept=yes
-else
+else $as_nop
   ac_cv_lib_m_feenableexcept=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_feenableexcept" >&5
-$as_echo "$ac_cv_lib_m_feenableexcept" >&6; }
-if test "x$ac_cv_lib_m_feenableexcept" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBM 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_feenableexcept" >&5
+printf "%s\n" "$ac_cv_lib_m_feenableexcept" >&6; }
+if test "x$ac_cv_lib_m_feenableexcept" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBM 1" >>confdefs.h
 
   LIBS="-lm $LIBS"
 
 fi
 
-for ac_func in feenableexcept
-do :
-  ac_fn_c_check_func "$LINENO" "feenableexcept" "ac_cv_func_feenableexcept"
-if test "x$ac_cv_func_feenableexcept" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_FEENABLEEXCEPT 1
-_ACEOF
+ac_fn_c_check_func "$LINENO" "feenableexcept" "ac_cv_func_feenableexcept"
+if test "x$ac_cv_func_feenableexcept" = xyes
+then :
+  printf "%s\n" "#define HAVE_FEENABLEEXCEPT 1" >>confdefs.h
 
 fi
-done
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if using Solaris linker" >&5
-$as_echo_n "checking if using Solaris linker... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if using Solaris linker" >&5
+printf %s "checking if using Solaris linker... " >&6; }
 SLD=`$LD --version 2>&1 | grep Solaris`
 if test "$SLD"; then
     have_solaris_ld=yes
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
     have_solaris_ld=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
  if test "$have_solaris_ld" = "yes"; then
   HAVE_SOLARIS_LD_TRUE=
@@ -13330,16 +13867,16 @@
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if libraries can be versioned" >&5
-$as_echo_n "checking if libraries can be versioned... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if libraries can be versioned" >&5
+printf %s "checking if libraries can be versioned... " >&6; }
 # Special case for PE/COFF platforms: ld reports
 # support for version-script, but doesn't actually
 # DO anything with it.
 case $host in
 *cygwin* | *mingw32* | *interix* )
     have_ld_version_script=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 ;;
 * )
 
@@ -13351,14 +13888,14 @@
 
 if test "$GLD"; then
     have_ld_version_script=yes
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
     have_ld_version_script=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: *** You have not enabled versioned symbols." >&5
-$as_echo "$as_me: WARNING: *** You have not enabled versioned symbols." >&2;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: *** You have not enabled versioned symbols." >&5
+printf "%s\n" "$as_me: WARNING: *** You have not enabled versioned symbols." >&2;}
 fi
 ;;
 esac
@@ -13373,15 +13910,15 @@
 
 
 if test "$have_ld_version_script" = "yes"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for symbol prefix" >&5
-$as_echo_n "checking for symbol prefix... " >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for symbol prefix" >&5
+printf %s "checking for symbol prefix... " >&6; }
     SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
                   | ${CPP-${CC-gcc} -E} - 2>&1 \
                   | ${EGREP-grep} "^PREFIX=" \
                   | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $SYMBOL_PREFIX" >&5
-$as_echo "$SYMBOL_PREFIX" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $SYMBOL_PREFIX" >&5
+printf "%s\n" "$SYMBOL_PREFIX" >&6; }
 fi
 
 # Substitutions for .in files
@@ -13394,29 +13931,31 @@
 # Allow the pkg-config directory to be set
 
 # Check whether --with-pkgconfigdir was given.
-if test "${with_pkgconfigdir+set}" = set; then :
+if test ${with_pkgconfigdir+y}
+then :
   withval=$with_pkgconfigdir; pkgconfigdir=${withval}
-else
+else $as_nop
   pkgconfigdir='${libdir}/pkgconfig'
 fi
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: pkgconfig directory is ${pkgconfigdir}" >&5
-$as_echo "$as_me: pkgconfig directory is ${pkgconfigdir}" >&6;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: pkgconfig directory is ${pkgconfigdir}" >&5
+printf "%s\n" "$as_me: pkgconfig directory is ${pkgconfigdir}" >&6;}
 
 # Make the *-config binary config scripts optional
 
 # Check whether --with-binconfigs was given.
-if test "${with_binconfigs+set}" = set; then :
+if test ${with_binconfigs+y}
+then :
   withval=$with_binconfigs; if test "${withval}" = no; then
       binconfigs=
-      { $as_echo "$as_me:${as_lineno-$LINENO}: libpng-config scripts will not be built" >&5
-$as_echo "$as_me: libpng-config scripts will not be built" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: libpng-config scripts will not be built" >&5
+printf "%s\n" "$as_me: libpng-config scripts will not be built" >&6;}
     else
       binconfigs='${binconfigs}'
     fi
-else
+else $as_nop
   binconfigs='${binconfigs}'
 fi
 
@@ -13426,7 +13965,8 @@
 # at the start of the build to rename exported library functions
 
 # Check whether --with-libpng-prefix was given.
-if test "${with_libpng_prefix+set}" = set; then :
+if test ${with_libpng_prefix+y}
+then :
   withval=$with_libpng_prefix; if test "${withval:-no}" != "no"; then
       PNG_PREFIX=${withval}
 
@@ -13446,7 +13986,8 @@
 # always installed, when the following options are turned on corresponding
 # unversioned links are also created (normally as symbolic links):
 # Check whether --enable-unversioned-links was given.
-if test "${enable_unversioned_links+set}" = set; then :
+if test ${enable_unversioned_links+y}
+then :
   enableval=$enable_unversioned_links;
 fi
 
@@ -13463,7 +14004,8 @@
 
 
 # Check whether --enable-unversioned-libpng-pc was given.
-if test "${enable_unversioned_libpng_pc+set}" = set; then :
+if test ${enable_unversioned_libpng_pc+y}
+then :
   enableval=$enable_unversioned_libpng_pc;
 fi
 
@@ -13477,7 +14019,8 @@
 
 
 # Check whether --enable-unversioned-libpng-config was given.
-if test "${enable_unversioned_libpng_config+set}" = set; then :
+if test ${enable_unversioned_libpng_config+y}
+then :
   enableval=$enable_unversioned_libpng_config;
 fi
 
@@ -13490,32 +14033,33 @@
 fi
 
 
-# HOST SPECIFIC OPTIONS
+# HOST-SPECIFIC OPTIONS
 # =====================
 #
 # DEFAULT
 # =======
 #
 # Check whether --enable-hardware-optimizations was given.
-if test "${enable_hardware_optimizations+set}" = set; then :
+if test ${enable_hardware_optimizations+y}
+then :
   enableval=$enable_hardware_optimizations; case "$enableval" in
       no|off)
          # disable hardware optimization on all systems:
          enable_arm_neon=no
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
 
          enable_mips_msa=no
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
 
          enable_powerpc_vsx=no
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
 
          enable_intel_sse=no
 
-$as_echo "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
 
          ;;
       *)
@@ -13524,25 +14068,25 @@
             arm*|aarch64*)
               enable_arm_neon=yes
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
 
               ;;
             mipsel*|mips64el*)
               enable_mips_msa=yes
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
 
               ;;
             i?86|x86_64)
               enable_intel_sse=yes
 
-$as_echo "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
 
               ;;
             powerpc*|ppc64*)
               enable_powerpc_vsx=yes
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
 
               ;;
          esac
@@ -13557,31 +14101,32 @@
 # ARM NEON (SIMD) support.
 
 # Check whether --enable-arm-neon was given.
-if test "${enable_arm_neon+set}" = set; then :
+if test ${enable_arm_neon+y}
+then :
   enableval=$enable_arm_neon; case "$enableval" in
       no|off)
          # disable the default enabling on __ARM_NEON__ systems:
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_arm_neon=no;;
+         enable_arm_neon=no ;;
       check)
 
-$as_echo "#define PNG_ARM_NEON_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_CHECK_SUPPORTED /**/" >>confdefs.h
 ;;
       api)
 
-$as_echo "#define PNG_ARM_NEON_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass -mfpu=neon
             to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
+printf "%s\n" "$as_me: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass -mfpu=neon
             to the compiler." >&2;};;
       *)
@@ -13590,14 +14135,14 @@
 fi
 
 
-# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
-# where ARM optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'arm*')
+# Add ARM-specific files to all builds where $host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'arm*')
 
  if test "$enable_arm_neon" != 'no' &&
     case "$host_cpu" in
-      arm*|aarch64*) :;;
-      *)    test "$enable_arm_neon" != '';;
+      arm*|aarch64*) : ;;
+      *)    test "$enable_arm_neon" != '' ;;
     esac; then
   PNG_ARM_NEON_TRUE=
   PNG_ARM_NEON_FALSE='#'
@@ -13608,36 +14153,37 @@
 
 
 # MIPS
-# ===
+# ====
 #
 # MIPS MSA (SIMD) support.
 
 # Check whether --enable-mips-msa was given.
-if test "${enable_mips_msa+set}" = set; then :
+if test ${enable_mips_msa+y}
+then :
   enableval=$enable_mips_msa; case "$enableval" in
       no|off)
          # disable the default enabling on __mips_msa systems:
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no;;
+         enable_mips_msa=no ;;
       check)
 
-$as_echo "#define PNG_MIPS_MSA_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_CHECK_SUPPORTED /**/" >>confdefs.h
 ;;
       api)
 
-$as_echo "#define PNG_MIPS_MSA_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-mmsa -mfp64'
             to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
+printf "%s\n" "$as_me: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-mmsa -mfp64'
             to the compiler." >&2;};;
       *)
@@ -13646,13 +14192,13 @@
 fi
 
 
-# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
-# where MIPS optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'mips*')
+# Add MIPS-specific files to all builds where $host_cpu is mips ('mips*') or
+# where MIPS optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'mips*')
 
  if test "$enable_mips_msa" != 'no' &&
     case "$host_cpu" in
-      mipsel*|mips64el*) :;;
+      mipsel*|mips64el*) : ;;
     esac; then
   PNG_MIPS_MSA_TRUE=
   PNG_MIPS_MSA_FALSE='#'
@@ -13668,18 +14214,19 @@
 # INTEL SSE (SIMD) support.
 
 # Check whether --enable-intel-sse was given.
-if test "${enable_intel_sse+set}" = set; then :
+if test ${enable_intel_sse+y}
+then :
   enableval=$enable_intel_sse; case "$enableval" in
       no|off)
          # disable the default enabling:
 
-$as_echo "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
+         enable_intel_sse=no ;;
       yes|on)
 
-$as_echo "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
 ;;
       *)
          as_fn_error $? "--enable-intel-sse=${enable_intel_sse}: invalid value" "$LINENO" 5
@@ -13687,13 +14234,13 @@
 fi
 
 
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
+# Add Intel-specific files to all builds where $host_cpu is Intel ('x86*') or
+# where Intel optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'x86*')
  if test "$enable_intel_sse" != 'no' &&
     case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
+      i?86|x86_64) : ;;
+      *)    test "$enable_intel_sse" != '' ;;
     esac; then
   PNG_INTEL_SSE_TRUE=
   PNG_INTEL_SSE_FALSE='#'
@@ -13704,55 +14251,56 @@
 
 
 # PowerPC
-# ===
+# =======
 #
 # PowerPC VSX (SIMD) support.
 
 # Check whether --enable-powerpc-vsx was given.
-if test "${enable_powerpc_vsx+set}" = set; then :
+if test ${enable_powerpc_vsx+y}
+then :
   enableval=$enable_powerpc_vsx; case "$enableval" in
       no|off)
          # disable the default enabling on __ppc64__ systems:
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
 
-         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no;;
+         # Prevent inclusion of the platform-specific files below:
+         enable_powerpc_vsx=no ;;
       check)
 
-$as_echo "#define PNG_POWERPC_VSX_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_CHECK_SUPPORTED /**/" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
             for the list of supported OSes." >&5
-$as_echo "$as_me: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
+printf "%s\n" "$as_me: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
             for the list of supported OSes." >&2;};;
       api)
 
-$as_echo "#define PNG_POWERPC_VSX_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-maltivec -mvsx'
-            or '-mcpu=power8'to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
+            or '-mcpu=power8' to the compiler." >&5
+printf "%s\n" "$as_me: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-maltivec -mvsx'
-            or '-mcpu=power8'to the compiler." >&2;};;
+            or '-mcpu=power8' to the compiler." >&2;};;
       *)
          as_fn_error $? "--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value" "$LINENO" 5
    esac
 fi
 
 
-# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'powerpc*')
+# Add PowerPC-specific files to all builds where $host_cpu is powerpc('powerpc*')
+# or where PowerPC optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'powerpc*')
 
  if test "$enable_powerpc_vsx" != 'no' &&
     case "$host_cpu" in
-      powerpc*|ppc64*) :;;
+      powerpc*|ppc64*) : ;;
     esac; then
   PNG_POWERPC_VSX_TRUE=
   PNG_POWERPC_VSX_FALSE='#'
@@ -13762,9 +14310,8 @@
 fi
 
 
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: Extra options for compiler: $PNG_COPTS" >&5
-$as_echo "$as_me: Extra options for compiler: $PNG_COPTS" >&6;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: Extra options for compiler: $PNG_COPTS" >&5
+printf "%s\n" "$as_me: Extra options for compiler: $PNG_COPTS" >&6;}
 
 # Config files, substituting as above
 ac_config_files="$ac_config_files Makefile libpng.pc:libpng.pc.in"
@@ -13799,8 +14346,8 @@
     case $ac_val in #(
     *${as_nl}*)
       case $ac_var in #(
-      *_cv_*) { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
-$as_echo "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
+      *_cv_*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
+printf "%s\n" "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
       esac
       case $ac_var in #(
       _ | IFS | as_nl) ;; #(
@@ -13830,15 +14377,15 @@
      /^ac_cv_env_/b end
      t clear
      :clear
-     s/^\([^=]*\)=\(.*[{}].*\)$/test "${\1+set}" = set || &/
+     s/^\([^=]*\)=\(.*[{}].*\)$/test ${\1+y} || &/
      t end
      s/^\([^=]*\)=\(.*\)$/\1=${\1=\2}/
      :end' >>confcache
 if diff "$cache_file" confcache >/dev/null 2>&1; then :; else
   if test -w "$cache_file"; then
     if test "x$cache_file" != "x/dev/null"; then
-      { $as_echo "$as_me:${as_lineno-$LINENO}: updating cache $cache_file" >&5
-$as_echo "$as_me: updating cache $cache_file" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: updating cache $cache_file" >&5
+printf "%s\n" "$as_me: updating cache $cache_file" >&6;}
       if test ! -f "$cache_file" || test -h "$cache_file"; then
 	cat confcache >"$cache_file"
       else
@@ -13852,8 +14399,8 @@
       fi
     fi
   else
-    { $as_echo "$as_me:${as_lineno-$LINENO}: not updating unwritable cache $cache_file" >&5
-$as_echo "$as_me: not updating unwritable cache $cache_file" >&6;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: not updating unwritable cache $cache_file" >&5
+printf "%s\n" "$as_me: not updating unwritable cache $cache_file" >&6;}
   fi
 fi
 rm -f confcache
@@ -13870,7 +14417,7 @@
 for ac_i in : $LIBOBJS; do test "x$ac_i" = x: && continue
   # 1. Remove the extension, and $U if already installed.
   ac_script='s/\$U\././;s/\.o$//;s/\.obj$//'
-  ac_i=`$as_echo "$ac_i" | sed "$ac_script"`
+  ac_i=`printf "%s\n" "$ac_i" | sed "$ac_script"`
   # 2. Prepend LIBOBJDIR.  When used with automake>=1.10 LIBOBJDIR
   #    will be set to the directory where LIBOBJS objects are built.
   as_fn_append ac_libobjs " \${LIBOBJDIR}$ac_i\$U.$ac_objext"
@@ -13881,14 +14428,14 @@
 LTLIBOBJS=$ac_ltlibobjs
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking that generated files are newer than configure" >&5
-$as_echo_n "checking that generated files are newer than configure... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking that generated files are newer than configure" >&5
+printf %s "checking that generated files are newer than configure... " >&6; }
    if test -n "$am_sleep_pid"; then
      # Hide warnings about reused PIDs.
      wait $am_sleep_pid 2>/dev/null
    fi
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: done" >&5
-$as_echo "done" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: done" >&5
+printf "%s\n" "done" >&6; }
  if test -n "$EXEEXT"; then
   am__EXEEXT_TRUE=
   am__EXEEXT_FALSE='#'
@@ -13962,8 +14509,8 @@
 ac_write_fail=0
 ac_clean_files_save=$ac_clean_files
 ac_clean_files="$ac_clean_files $CONFIG_STATUS"
-{ $as_echo "$as_me:${as_lineno-$LINENO}: creating $CONFIG_STATUS" >&5
-$as_echo "$as_me: creating $CONFIG_STATUS" >&6;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating $CONFIG_STATUS" >&5
+printf "%s\n" "$as_me: creating $CONFIG_STATUS" >&6;}
 as_write_fail=0
 cat >$CONFIG_STATUS <<_ASEOF || as_write_fail=1
 #! $SHELL
@@ -13986,14 +14533,16 @@
 
 # Be more Bourne compatible
 DUALCASE=1; export DUALCASE # for MKS sh
-if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then :
+as_nop=:
+if test ${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on ${1+"$@"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '${1+"$@"}'='"$@"'
   setopt NO_GLOB_SUBST
-else
+else $as_nop
   case `(set -o) 2>/dev/null` in #(
   *posix*) :
     set -o posix ;; #(
@@ -14003,46 +14552,46 @@
 fi
 
 
+
+# Reset variables that may have inherited troublesome values from
+# the environment.
+
+# IFS needs to be set, to space, tab, and newline, in precisely that order.
+# (If _AS_PATH_WALK were called with IFS unset, it would have the
+# side effect of setting IFS to empty, thus disabling word splitting.)
+# Quoting is to prevent editors from complaining about space-tab.
 as_nl='
 '
 export as_nl
-# Printing a long string crashes Solaris 7 /usr/bin/printf.
-as_echo='\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo$as_echo
-# Prefer a ksh shell builtin over an external printf program on Solaris,
-# but without wasting forks for bash or zsh.
-if test -z "$BASH_VERSION$ZSH_VERSION" \
-    && (test "X`print -r -- $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='print -r --'
-  as_echo_n='print -rn --'
-elif (test "X`printf %s $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='printf %s\n'
-  as_echo_n='printf %s'
-else
-  if test "X`(/usr/ucb/echo -n -n $as_echo) 2>/dev/null`" = "X-n $as_echo"; then
-    as_echo_body='eval /usr/ucb/echo -n "$1$as_nl"'
-    as_echo_n='/usr/ucb/echo -n'
-  else
-    as_echo_body='eval expr "X$1" : "X\\(.*\\)"'
-    as_echo_n_body='eval
-      arg=$1;
-      case $arg in #(
-      *"$as_nl"*)
-	expr "X$arg" : "X\\(.*\\)$as_nl";
-	arg=`expr "X$arg" : ".*$as_nl\\(.*\\)"`;;
-      esac;
-      expr "X$arg" : "X\\(.*\\)" | tr -d "$as_nl"
-    '
-    export as_echo_n_body
-    as_echo_n='sh -c $as_echo_n_body as_echo'
-  fi
-  export as_echo_body
-  as_echo='sh -c $as_echo_body as_echo'
-fi
+IFS=" ""	$as_nl"
+
+PS1='$ '
+PS2='> '
+PS4='+ '
+
+# Ensure predictable behavior from utilities with locale-dependent output.
+LC_ALL=C
+export LC_ALL
+LANGUAGE=C
+export LANGUAGE
+
+# We cannot yet rely on "unset" to work, but we need these variables
+# to be unset--not just set to an empty or harmless value--now, to
+# avoid bugs in old shells (e.g. pre-3.0 UWIN ksh).  This construct
+# also avoids known problems related to "unset" and subshell syntax
+# in other old shells (e.g. bash 2.01 and pdksh 5.2.14).
+for as_var in BASH_ENV ENV MAIL MAILPATH CDPATH
+do eval test \${$as_var+y} \
+  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
+done
+
+# Ensure that fds 0, 1, and 2 are open.
+if (exec 3>&0) 2>/dev/null; then :; else exec 0</dev/null; fi
+if (exec 3>&1) 2>/dev/null; then :; else exec 1>/dev/null; fi
+if (exec 3>&2)            ; then :; else exec 2>/dev/null; fi
 
 # The user is always right.
-if test "${PATH_SEPARATOR+set}" != set; then
+if ${PATH_SEPARATOR+false} :; then
   PATH_SEPARATOR=:
   (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 && {
     (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 ||
@@ -14051,13 +14600,6 @@
 fi
 
 
-# IFS
-# We need space, tab and new line, in precisely that order.  Quoting is
-# there to prevent editors from complaining about space-tab.
-# (If _AS_PATH_WALK were called with IFS unset, it would disable word
-# splitting by setting IFS to empty value.)
-IFS=" ""	$as_nl"
-
 # Find who we are.  Look in the path if we contain no directory separator.
 as_myself=
 case $0 in #((
@@ -14066,8 +14608,12 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    test -r "$as_dir/$0" && as_myself=$as_dir/$0 && break
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    test -r "$as_dir$0" && as_myself=$as_dir$0 && break
   done
 IFS=$as_save_IFS
 
@@ -14079,30 +14625,10 @@
   as_myself=$0
 fi
 if test ! -f "$as_myself"; then
-  $as_echo "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
+  printf "%s\n" "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
   exit 1
 fi
 
-# Unset variables that we do not need and which cause bugs (e.g. in
-# pre-3.0 UWIN ksh).  But do not cause bugs in bash 2.01; the "|| exit 1"
-# suppresses any "Segmentation fault" message there.  '((' could
-# trigger a bug in pdksh 5.2.14.
-for as_var in BASH_ENV ENV MAIL MAILPATH
-do eval test x\${$as_var+set} = xset \
-  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
-done
-PS1='$ '
-PS2='> '
-PS4='+ '
-
-# NLS nuisances.
-LC_ALL=C
-export LC_ALL
-LANGUAGE=C
-export LANGUAGE
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
 
 
 # as_fn_error STATUS ERROR [LINENO LOG_FD]
@@ -14115,13 +14641,14 @@
   as_status=$1; test $as_status -eq 0 && as_status=1
   if test "$4"; then
     as_lineno=${as_lineno-"$3"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-    $as_echo "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
   fi
-  $as_echo "$as_me: error: $2" >&2
+  printf "%s\n" "$as_me: error: $2" >&2
   as_fn_exit $as_status
 } # as_fn_error
 
 
+
 # as_fn_set_status STATUS
 # -----------------------
 # Set $? to STATUS, without forking.
@@ -14148,18 +14675,20 @@
   { eval $1=; unset $1;}
 }
 as_unset=as_fn_unset
+
 # as_fn_append VAR VALUE
 # ----------------------
 # Append the text in VALUE to the end of the definition contained in VAR. Take
 # advantage of any shell optimizations that allow amortized linear growth over
 # repeated appends, instead of the typical quadratic growth present in naive
 # implementations.
-if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null; then :
+if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null
+then :
   eval 'as_fn_append ()
   {
     eval $1+=\$2
   }'
-else
+else $as_nop
   as_fn_append ()
   {
     eval $1=\$$1\$2
@@ -14171,12 +14700,13 @@
 # Perform arithmetic evaluation on the ARGs, and store the result in the
 # global $as_val. Take advantage of shells that can avoid forks. The arguments
 # must be portable across $(()) and expr.
-if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null; then :
+if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null
+then :
   eval 'as_fn_arith ()
   {
     as_val=$(( $* ))
   }'
-else
+else $as_nop
   as_fn_arith ()
   {
     as_val=`expr "$@" || test $? -eq 1`
@@ -14207,7 +14737,7 @@
 $as_expr X/"$0" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$0" : 'X\(//\)$' \| \
 	 X"$0" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$0" |
+printf "%s\n" X/"$0" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -14229,6 +14759,10 @@
 as_cr_digits='0123456789'
 as_cr_alnum=$as_cr_Letters$as_cr_digits
 
+
+# Determine whether it's possible to make 'echo' print without a newline.
+# These variables are no longer used directly by Autoconf, but are AC_SUBSTed
+# for compatibility with existing Makefiles.
 ECHO_C= ECHO_N= ECHO_T=
 case `echo -n x` in #(((((
 -n*)
@@ -14242,6 +14776,12 @@
   ECHO_N='-n';;
 esac
 
+# For backward compatibility with old third-party macros, we provide
+# the shell variables $as_echo and $as_echo_n.  New code should use
+# AS_ECHO(["message"]) and AS_ECHO_N(["message"]), respectively.
+as_echo='printf %s\n'
+as_echo_n='printf %s'
+
 rm -f conf$$ conf$$.exe conf$$.file
 if test -d conf$$.dir; then
   rm -f conf$$.dir/conf$$.file
@@ -14283,7 +14823,7 @@
     as_dirs=
     while :; do
       case $as_dir in #(
-      *\'*) as_qdir=`$as_echo "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
+      *\'*) as_qdir=`printf "%s\n" "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
       *) as_qdir=$as_dir;;
       esac
       as_dirs="'$as_qdir' $as_dirs"
@@ -14292,7 +14832,7 @@
 	 X"$as_dir" : 'X\(//\)[^/]' \| \
 	 X"$as_dir" : 'X\(//\)$' \| \
 	 X"$as_dir" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_dir" |
+printf "%s\n" X"$as_dir" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -14354,8 +14894,8 @@
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by libpng $as_me 1.6.37, which was
-generated by GNU Autoconf 2.69.  Invocation command line was
+This file was extended by libpng $as_me 1.6.38, which was
+generated by GNU Autoconf 2.71.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
   CONFIG_HEADERS  = $CONFIG_HEADERS
@@ -14417,14 +14957,16 @@
 Report bugs to <png-mng-implement@lists.sourceforge.net>."
 
 _ACEOF
+ac_cs_config=`printf "%s\n" "$ac_configure_args" | sed "$ac_safe_unquote"`
+ac_cs_config_escaped=`printf "%s\n" "$ac_cs_config" | sed "s/^ //; s/'/'\\\\\\\\''/g"`
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
-ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
+ac_cs_config='$ac_cs_config_escaped'
 ac_cs_version="\\
-libpng config.status 1.6.37
-configured by $0, generated by GNU Autoconf 2.69,
+libpng config.status 1.6.38
+configured by $0, generated by GNU Autoconf 2.71,
   with options \\"\$ac_cs_config\\"
 
-Copyright (C) 2012 Free Software Foundation, Inc.
+Copyright (C) 2021 Free Software Foundation, Inc.
 This config.status script is free software; the Free Software Foundation
 gives unlimited permission to copy, distribute and modify it."
 
@@ -14464,15 +15006,15 @@
   -recheck | --recheck | --rechec | --reche | --rech | --rec | --re | --r)
     ac_cs_recheck=: ;;
   --version | --versio | --versi | --vers | --ver | --ve | --v | -V )
-    $as_echo "$ac_cs_version"; exit ;;
+    printf "%s\n" "$ac_cs_version"; exit ;;
   --config | --confi | --conf | --con | --co | --c )
-    $as_echo "$ac_cs_config"; exit ;;
+    printf "%s\n" "$ac_cs_config"; exit ;;
   --debug | --debu | --deb | --de | --d | -d )
     debug=: ;;
   --file | --fil | --fi | --f )
     $ac_shift
     case $ac_optarg in
-    *\'*) ac_optarg=`$as_echo "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_optarg=`printf "%s\n" "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
     '') as_fn_error $? "missing file argument" ;;
     esac
     as_fn_append CONFIG_FILES " '$ac_optarg'"
@@ -14480,7 +15022,7 @@
   --header | --heade | --head | --hea )
     $ac_shift
     case $ac_optarg in
-    *\'*) ac_optarg=`$as_echo "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_optarg=`printf "%s\n" "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
     esac
     as_fn_append CONFIG_HEADERS " '$ac_optarg'"
     ac_need_defaults=false;;
@@ -14489,7 +15031,7 @@
     as_fn_error $? "ambiguous option: \`$1'
 Try \`$0 --help' for more information.";;
   --help | --hel | -h )
-    $as_echo "$ac_cs_usage"; exit ;;
+    printf "%s\n" "$ac_cs_usage"; exit ;;
   -q | -quiet | --quiet | --quie | --qui | --qu | --q \
   | -silent | --silent | --silen | --sile | --sil | --si | --s)
     ac_cs_silent=: ;;
@@ -14517,7 +15059,7 @@
 if \$ac_cs_recheck; then
   set X $SHELL '$0' $ac_configure_args \$ac_configure_extra_args --no-create --no-recursion
   shift
-  \$as_echo "running CONFIG_SHELL=$SHELL \$*" >&6
+  \printf "%s\n" "running CONFIG_SHELL=$SHELL \$*" >&6
   CONFIG_SHELL='$SHELL'
   export CONFIG_SHELL
   exec "\$@"
@@ -14531,7 +15073,7 @@
   sed 'h;s/./-/g;s/^.../## /;s/...$/ ##/;p;x;p;x' <<_ASBOX
 ## Running $as_me. ##
 _ASBOX
-  $as_echo "$ac_log"
+  printf "%s\n" "$ac_log"
 } >&5
 
 _ACEOF
@@ -14586,12 +15128,14 @@
 lt_cv_to_tool_file_cmd='`$ECHO "$lt_cv_to_tool_file_cmd" | $SED "$delay_single_quote_subst"`'
 reload_flag='`$ECHO "$reload_flag" | $SED "$delay_single_quote_subst"`'
 reload_cmds='`$ECHO "$reload_cmds" | $SED "$delay_single_quote_subst"`'
+FILECMD='`$ECHO "$FILECMD" | $SED "$delay_single_quote_subst"`'
 deplibs_check_method='`$ECHO "$deplibs_check_method" | $SED "$delay_single_quote_subst"`'
 file_magic_cmd='`$ECHO "$file_magic_cmd" | $SED "$delay_single_quote_subst"`'
 file_magic_glob='`$ECHO "$file_magic_glob" | $SED "$delay_single_quote_subst"`'
 want_nocaseglob='`$ECHO "$want_nocaseglob" | $SED "$delay_single_quote_subst"`'
 sharedlib_from_linklib_cmd='`$ECHO "$sharedlib_from_linklib_cmd" | $SED "$delay_single_quote_subst"`'
 AR='`$ECHO "$AR" | $SED "$delay_single_quote_subst"`'
+lt_ar_flags='`$ECHO "$lt_ar_flags" | $SED "$delay_single_quote_subst"`'
 AR_FLAGS='`$ECHO "$AR_FLAGS" | $SED "$delay_single_quote_subst"`'
 archiver_list_spec='`$ECHO "$archiver_list_spec" | $SED "$delay_single_quote_subst"`'
 STRIP='`$ECHO "$STRIP" | $SED "$delay_single_quote_subst"`'
@@ -14715,13 +15259,13 @@
 lt_SP2NL \
 lt_NL2SP \
 reload_flag \
+FILECMD \
 deplibs_check_method \
 file_magic_cmd \
 file_magic_glob \
 want_nocaseglob \
 sharedlib_from_linklib_cmd \
 AR \
-AR_FLAGS \
 archiver_list_spec \
 STRIP \
 RANLIB \
@@ -14851,9 +15395,9 @@
 # We use the long form for the default assignment because of an extremely
 # bizarre bug on SunOS 4.1.3.
 if $ac_need_defaults; then
-  test "${CONFIG_FILES+set}" = set || CONFIG_FILES=$config_files
-  test "${CONFIG_HEADERS+set}" = set || CONFIG_HEADERS=$config_headers
-  test "${CONFIG_COMMANDS+set}" = set || CONFIG_COMMANDS=$config_commands
+  test ${CONFIG_FILES+y} || CONFIG_FILES=$config_files
+  test ${CONFIG_HEADERS+y} || CONFIG_HEADERS=$config_headers
+  test ${CONFIG_COMMANDS+y} || CONFIG_COMMANDS=$config_commands
 fi
 
 # Have a temporary directory for convenience.  Make it in the build tree
@@ -15189,7 +15733,7 @@
 	   esac ||
 	   as_fn_error 1 "cannot find input file: \`$ac_f'" "$LINENO" 5;;
       esac
-      case $ac_f in *\'*) ac_f=`$as_echo "$ac_f" | sed "s/'/'\\\\\\\\''/g"`;; esac
+      case $ac_f in *\'*) ac_f=`printf "%s\n" "$ac_f" | sed "s/'/'\\\\\\\\''/g"`;; esac
       as_fn_append ac_file_inputs " '$ac_f'"
     done
 
@@ -15197,17 +15741,17 @@
     # use $as_me), people would be surprised to read:
     #    /* config.h.  Generated by config.status.  */
     configure_input='Generated from '`
-	  $as_echo "$*" | sed 's|^[^:]*/||;s|:[^:]*/|, |g'
+	  printf "%s\n" "$*" | sed 's|^[^:]*/||;s|:[^:]*/|, |g'
 	`' by configure.'
     if test x"$ac_file" != x-; then
       configure_input="$ac_file.  $configure_input"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: creating $ac_file" >&5
-$as_echo "$as_me: creating $ac_file" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating $ac_file" >&5
+printf "%s\n" "$as_me: creating $ac_file" >&6;}
     fi
     # Neutralize special characters interpreted by sed in replacement strings.
     case $configure_input in #(
     *\&* | *\|* | *\\* )
-       ac_sed_conf_input=`$as_echo "$configure_input" |
+       ac_sed_conf_input=`printf "%s\n" "$configure_input" |
        sed 's/[\\\\&|]/\\\\&/g'`;; #(
     *) ac_sed_conf_input=$configure_input;;
     esac
@@ -15224,7 +15768,7 @@
 	 X"$ac_file" : 'X\(//\)[^/]' \| \
 	 X"$ac_file" : 'X\(//\)$' \| \
 	 X"$ac_file" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$ac_file" |
+printf "%s\n" X"$ac_file" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15248,9 +15792,9 @@
 case "$ac_dir" in
 .) ac_dir_suffix= ac_top_builddir_sub=. ac_top_build_prefix= ;;
 *)
-  ac_dir_suffix=/`$as_echo "$ac_dir" | sed 's|^\.[\\/]||'`
+  ac_dir_suffix=/`printf "%s\n" "$ac_dir" | sed 's|^\.[\\/]||'`
   # A ".." for each directory in $ac_dir_suffix.
-  ac_top_builddir_sub=`$as_echo "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
+  ac_top_builddir_sub=`printf "%s\n" "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
   case $ac_top_builddir_sub in
   "") ac_top_builddir_sub=. ac_top_build_prefix= ;;
   *)  ac_top_build_prefix=$ac_top_builddir_sub/ ;;
@@ -15312,8 +15856,8 @@
 case `eval "sed -n \"\$ac_sed_dataroot\" $ac_file_inputs"` in
 *datarootdir*) ac_datarootdir_seen=yes;;
 *@datadir@*|*@docdir@*|*@infodir@*|*@localedir@*|*@mandir@*)
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&5
-$as_echo "$as_me: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&5
+printf "%s\n" "$as_me: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&2;}
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
   ac_datarootdir_hack='
@@ -15357,9 +15901,9 @@
   { ac_out=`sed -n '/\${datarootdir}/p' "$ac_tmp/out"`; test -n "$ac_out"; } &&
   { ac_out=`sed -n '/^[	 ]*datarootdir[	 ]*:*=/p' \
       "$ac_tmp/out"`; test -z "$ac_out"; } &&
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file contains a reference to the variable \`datarootdir'
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file contains a reference to the variable \`datarootdir'
 which seems to be undefined.  Please make sure it is defined" >&5
-$as_echo "$as_me: WARNING: $ac_file contains a reference to the variable \`datarootdir'
+printf "%s\n" "$as_me: WARNING: $ac_file contains a reference to the variable \`datarootdir'
 which seems to be undefined.  Please make sure it is defined" >&2;}
 
   rm -f "$ac_tmp/stdin"
@@ -15375,20 +15919,20 @@
   #
   if test x"$ac_file" != x-; then
     {
-      $as_echo "/* $configure_input  */" \
+      printf "%s\n" "/* $configure_input  */" >&1 \
       && eval '$AWK -f "$ac_tmp/defines.awk"' "$ac_file_inputs"
     } >"$ac_tmp/config.h" \
       || as_fn_error $? "could not create $ac_file" "$LINENO" 5
     if diff "$ac_file" "$ac_tmp/config.h" >/dev/null 2>&1; then
-      { $as_echo "$as_me:${as_lineno-$LINENO}: $ac_file is unchanged" >&5
-$as_echo "$as_me: $ac_file is unchanged" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: $ac_file is unchanged" >&5
+printf "%s\n" "$as_me: $ac_file is unchanged" >&6;}
     else
       rm -f "$ac_file"
       mv "$ac_tmp/config.h" "$ac_file" \
 	|| as_fn_error $? "could not create $ac_file" "$LINENO" 5
     fi
   else
-    $as_echo "/* $configure_input  */" \
+    printf "%s\n" "/* $configure_input  */" >&1 \
       && eval '$AWK -f "$ac_tmp/defines.awk"' "$ac_file_inputs" \
       || as_fn_error $? "could not create -" "$LINENO" 5
   fi
@@ -15408,7 +15952,7 @@
 	 X"$_am_arg" : 'X\(//\)[^/]' \| \
 	 X"$_am_arg" : 'X\(//\)$' \| \
 	 X"$_am_arg" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$_am_arg" |
+printf "%s\n" X"$_am_arg" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15428,8 +15972,8 @@
 	  s/.*/./; q'`/stamp-h$_am_stamp_count
  ;;
 
-  :C)  { $as_echo "$as_me:${as_lineno-$LINENO}: executing $ac_file commands" >&5
-$as_echo "$as_me: executing $ac_file commands" >&6;}
+  :C)  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: executing $ac_file commands" >&5
+printf "%s\n" "$as_me: executing $ac_file commands" >&6;}
  ;;
   esac
 
@@ -15455,7 +15999,7 @@
   for am_mf
   do
     # Strip MF so we end up with the name of the file.
-    am_mf=`$as_echo "$am_mf" | sed -e 's/:.*$//'`
+    am_mf=`printf "%s\n" "$am_mf" | sed -e 's/:.*$//'`
     # Check whether this is an Automake generated Makefile which includes
     # dependency-tracking related rules and includes.
     # Grep'ing the whole file directly is not great: AIX grep has a line
@@ -15467,7 +16011,7 @@
 	 X"$am_mf" : 'X\(//\)[^/]' \| \
 	 X"$am_mf" : 'X\(//\)$' \| \
 	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$am_mf" |
+printf "%s\n" X"$am_mf" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15489,7 +16033,7 @@
 $as_expr X/"$am_mf" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$am_mf" : 'X\(//\)$' \| \
 	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$am_mf" |
+printf "%s\n" X/"$am_mf" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -15514,10 +16058,12 @@
    (exit $ac_status); } || am_rc=$?
   done
   if test $am_rc -ne 0; then
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in \`$ac_pwd':" >&2;}
 as_fn_error $? "Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  Try re-running configure with the
+    for automatic dependency tracking.  If GNU make was not used, consider
+    re-running the configure script with MAKE=\"gmake\" (or whatever is
+    necessary).  You can also try re-running configure with the
     '--disable-dependency-tracking' option to at least be able to build
     the package (albeit without support for automatic dependency tracking).
 See \`config.log' for more details" "$LINENO" 5; }
@@ -15673,6 +16219,9 @@
 # convert \$build files to toolchain format.
 to_tool_file_cmd=$lt_cv_to_tool_file_cmd
 
+# A file(cmd) program that detects file types.
+FILECMD=$lt_FILECMD
+
 # Method to check whether dependent libraries are shared objects.
 deplibs_check_method=$lt_deplibs_check_method
 
@@ -15691,8 +16240,11 @@
 # The archiver.
 AR=$lt_AR
 
+# Flags to create an archive (by configure).
+lt_ar_flags=$lt_ar_flags
+
 # Flags to create an archive.
-AR_FLAGS=$lt_AR_FLAGS
+AR_FLAGS=\${ARFLAGS-"\$lt_ar_flags"}
 
 # How to feed a file listing to the archiver.
 archiver_list_spec=$lt_archiver_list_spec
@@ -16060,6 +16612,7 @@
   esac
 
 
+
 ltmain=$ac_aux_dir/ltmain.sh
 
 
@@ -16067,7 +16620,7 @@
   # if finds mixed CR/LF and LF-only lines.  Since sed operates in
   # text mode, it properly converts lines to CR/LF.  This bash problem
   # is reportedly fixed, but why not run on old versions too?
-  sed '$q' "$ltmain" >> "$cfgfile" \
+  $SED '$q' "$ltmain" >> "$cfgfile" \
      || (rm -f "$cfgfile"; exit 1)
 
    mv -f "$cfgfile" "$ofile" ||
@@ -16110,7 +16663,8 @@
   $ac_cs_success || as_fn_exit 1
 fi
 if test -n "$ac_unrecognized_opts" && test "$enable_option_checking" != no; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: unrecognized options: $ac_unrecognized_opts" >&5
-$as_echo "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: unrecognized options: $ac_unrecognized_opts" >&5
+printf "%s\n" "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2;}
 fi
 
+
diff --git a/configure.ac b/configure.ac
index 52dba94..7b6d5b9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 # configure.ac
 
-# Copyright (c) 2018 Cosmin Truta
+# Copyright (c) 2018-2022 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 
 # This code is released under the libpng license.
@@ -25,7 +25,7 @@
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.6.37],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.38],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -46,10 +46,10 @@
 dnl AM_PREREQ([1.11.2])
 dnl stop configure from automagically running automake
 
-PNGLIB_VERSION=1.6.37
+PNGLIB_VERSION=1.6.38
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=37
+PNGLIB_RELEASE=38
 
 dnl End of version number stuff
 
@@ -89,9 +89,9 @@
 DFNCPP="$CPP"
 AC_SUBST(DFNCPP)
 
-# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
-# checks the compiler with a program that generates a warning), add the
-# following option to deal with this
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail
+# (it checks the compiler with a program that generates a warning).
+# Add the following option to deal with this:
 AC_ARG_VAR(PNG_COPTS,
    [additional flags for the C compiler, use this for options that would]
    [cause configure itself to fail])
@@ -114,10 +114,10 @@
       CFLAGS="$sav_CFLAGS"
     fi],)
 
-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the 
-# "-std=c89" compiler option:
+# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89.
+# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining
+# _POSIX_SOURCE to 1. This is incompatible with the new default mode, so
+# we test for that and force the "-std=c89" compiler option:
 AC_MSG_CHECKING([if we need to force back C standard to C89])
 AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([
@@ -133,22 +133,16 @@
    CFLAGS="$CFLAGS -std=c89"
 ])
 
-# Checks for header files.
-AC_HEADER_STDC
-
-# Checks for typedefs, structures, and compiler characteristics.
-AC_C_CONST
-AC_TYPE_SIZE_T
+# Checks for structures and compiler characteristics.
 AC_STRUCT_TM
 AC_C_RESTRICT
 
 # Checks for library functions.
-AC_FUNC_STRTOD
-AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
+AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)))
 
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
-AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
+# Some later POSIX 1003.1 functions are required for test programs, failure
+# here is soft (the corresponding test program is not built).
+AC_CHECK_FUNC([clock_gettime], , [AC_MSG_WARN([not building timepng])])
 AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
 
 AC_ARG_WITH(zlib-prefix,
@@ -296,7 +290,7 @@
 AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
    [test "$enable_unversioned_libpng_config" != "no"])
 
-# HOST SPECIFIC OPTIONS
+# HOST-SPECIFIC OPTIONS
 # =====================
 #
 # DEFAULT
@@ -326,12 +320,12 @@
          case "$host_cpu" in
             arm*|aarch64*)
               enable_arm_neon=yes
-              AC_DEFINE([PNG_ARM_NEON_OPT], [0],
+              AC_DEFINE([PNG_ARM_NEON_OPT], [2],
                 [Enable ARM_NEON optimizations])
               ;;
             mipsel*|mips64el*)
               enable_mips_msa=yes
-              AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
+              AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
                 [Enable MIPS_MSA optimizations])
               ;;
             i?86|x86_64)
@@ -366,7 +360,7 @@
          AC_DEFINE([PNG_ARM_NEON_OPT], [0],
                    [Disable ARM Neon optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_arm_neon=no;;
+         enable_arm_neon=no ;;
       check)
          AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
                    [Check for ARM Neon support at run-time]);;
@@ -383,19 +377,19 @@
          AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
    esac])
 
-# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
-# where ARM optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'arm*')
+# Add ARM-specific files to all builds where $host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'arm*')
 
 AM_CONDITIONAL([PNG_ARM_NEON],
    [test "$enable_arm_neon" != 'no' &&
     case "$host_cpu" in
-      arm*|aarch64*) :;;
-      *)    test "$enable_arm_neon" != '';;
+      arm*|aarch64*) : ;;
+      *)    test "$enable_arm_neon" != '' ;;
     esac])
 
 # MIPS
-# ===
+# ====
 #
 # MIPS MSA (SIMD) support.
 
@@ -412,7 +406,7 @@
          AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
                    [Disable MIPS MSA optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no;;
+         enable_mips_msa=no ;;
       check)
          AC_DEFINE([PNG_MIPS_MSA_CHECK_SUPPORTED], [],
                    [Check for MIPS MSA support at run-time]);;
@@ -429,14 +423,14 @@
          AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}: invalid value])
    esac])
 
-# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
-# where MIPS optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'mips*')
+# Add MIPS-specific files to all builds where $host_cpu is mips ('mips*') or
+# where MIPS optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'mips*')
 
 AM_CONDITIONAL([PNG_MIPS_MSA],
    [test "$enable_mips_msa" != 'no' &&
     case "$host_cpu" in
-      mipsel*|mips64el*) :;;
+      mipsel*|mips64el*) : ;;
     esac])
 
 # INTEL
@@ -456,7 +450,7 @@
          AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
                    [Disable Intel SSE optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
+         enable_intel_sse=no ;;
       yes|on)
          AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
                    [Enable Intel SSE optimizations]);;
@@ -464,18 +458,18 @@
          AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
    esac])
 
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
+# Add Intel-specific files to all builds where $host_cpu is Intel ('x86*') or
+# where Intel optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'x86*')
 AM_CONDITIONAL([PNG_INTEL_SSE],
    [test "$enable_intel_sse" != 'no' &&
     case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
+      i?86|x86_64) : ;;
+      *)    test "$enable_intel_sse" != '' ;;
     esac])
 
 # PowerPC
-# ===
+# =======
 #
 # PowerPC VSX (SIMD) support.
 
@@ -491,8 +485,8 @@
          # disable the default enabling on __ppc64__ systems:
          AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
                    [Disable POWERPC VSX optimizations])
-         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no;;
+         # Prevent inclusion of the platform-specific files below:
+         enable_powerpc_vsx=no ;;
       check)
          AC_DEFINE([PNG_POWERPC_VSX_CHECK_SUPPORTED], [],
                    [Check for POWERPC VSX support at run-time])
@@ -506,22 +500,21 @@
                    [Enable POWERPC VSX optimizations])
          AC_MSG_WARN([--enable-powerpc-vsx: please specify 'check' or 'api', if]
             [you want the optimizations unconditionally pass '-maltivec -mvsx']
-            [or '-mcpu=power8'to the compiler.]);;
+            [or '-mcpu=power8' to the compiler.]);;
       *)
          AC_MSG_ERROR([--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value])
    esac])
 
-# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'powerpc*')
+# Add PowerPC-specific files to all builds where $host_cpu is powerpc('powerpc*')
+# or where PowerPC optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'powerpc*')
 
 AM_CONDITIONAL([PNG_POWERPC_VSX],
    [test "$enable_powerpc_vsx" != 'no' &&
     case "$host_cpu" in
-      powerpc*|ppc64*) :;;
+      powerpc*|ppc64*) : ;;
     esac])
 
-
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
 
 # Config files, substituting as above
diff --git a/contrib/libtests/gentests.sh b/contrib/libtests/gentests.sh
index f0f8d23..eba7ce5 100755
--- a/contrib/libtests/gentests.sh
+++ b/contrib/libtests/gentests.sh
@@ -2,8 +2,6 @@
 #
 # Copyright (c) 2013 John Cunningham Bowler
 #
-# Last changed in libpng 1.6.0 [February 14, 2013]
-#
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
diff --git a/contrib/libtests/makepng.c b/contrib/libtests/makepng.c
index 312062b..e911c06 100644
--- a/contrib/libtests/makepng.c
+++ b/contrib/libtests/makepng.c
@@ -3,8 +3,6 @@
 /* Copyright: */
 #define COPYRIGHT "\251 2013,2015 John Cunningham Bowler"
 /*
- * Last changed in libpng 1.6.20 [November 24, 2015]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -299,25 +297,28 @@
             unsigned int x, y;
             volatile unsigned int ip = 0;
 
-            for (x=0; x<size; ++x) for (y=0; y<size; ++y)
+            for (x=0; x<size; ++x)
             {
-               ip = x + (size * y);
+               for (y=0; y<size; ++y)
+               {
+                  ip = x + (size * y);
 
-               /* size is at most 16, so the scaled value below fits in 16 bits
-                */
-#              define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
-#              define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
-                  (interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
-                  (size*size))
+                  /* size is at most 16, so the scaled value below fits in 16 bits
+                  */
+#                 define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
+#                 define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
+                     (interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
+                     (size*size))
 
-               set_color(palette+ip, trans+ip,
-                  /* color:    green, red,blue,white */
-                  xyinterp(x, y,   0, 255,   0, 255),
-                  xyinterp(x, y, 255,   0,   0, 255),
-                  xyinterp(x, y,   0,   0, 255, 255),
-                  /* alpha:        0, 102, 204, 255) */
-                  xyinterp(x, y,   0, 102, 204, 255),
-                  gamma_table);
+                  set_color(palette+ip, trans+ip,
+                     /* color:    green, red,blue,white */
+                     xyinterp(x, y,   0, 255,   0, 255),
+                     xyinterp(x, y, 255,   0,   0, 255),
+                     xyinterp(x, y,   0,   0, 255, 255),
+                     /* alpha:        0, 102, 204, 255) */
+                     xyinterp(x, y,   0, 102, 204, 255),
+                     gamma_table);
+               }
             }
 
             return ip+1;
@@ -396,7 +397,7 @@
       image_size_of_type(color_type, bit_depth, colors, small)-1;
    png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
 
-   if (colors[0] == 0) if (small)
+   if (colors[0] == 0 && small)
    {
       unsigned int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
 
@@ -858,10 +859,13 @@
       {
          unsigned int i;
 
-         if (real_gamma == 45455) for (i=0; i<256; ++i)
+         if (real_gamma == 45455)
          {
-            gamma_table[i] = (png_byte)i;
-            conv = 1.;
+            for (i=0; i<256; ++i)
+            {
+               gamma_table[i] = (png_byte)i;
+               conv = 1.;
+            }
          }
 
          else
@@ -1430,10 +1434,13 @@
    for (i=0; *param && i<nparams; ++i)
    {
       list[i] = param;
-      while (*++param) if (*param == '\n' || *param == ':')
+      while (*++param)
       {
-         *param++ = 0; /* Terminate last parameter */
-         break;        /* And start a new one. */
+         if (*param == '\n' || *param == ':')
+         {
+            *param++ = 0; /* Terminate last parameter */
+            break;        /* And start a new one. */
+         }
       }
    }
 
@@ -1869,7 +1876,7 @@
          }
    }
 
-   /* small and colors are incomparible (will probably crash if both are used at
+   /* small and colors are incompatible (will probably crash if both are used at
     * the same time!)
     */
    if (small && colors[0] != 0)
diff --git a/contrib/libtests/pngimage.c b/contrib/libtests/pngimage.c
index f130c04..be176b2 100644
--- a/contrib/libtests/pngimage.c
+++ b/contrib/libtests/pngimage.c
@@ -1,9 +1,9 @@
+
 /* pngimage.c
  *
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2015,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.24 [August 4, 2016]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -12,6 +12,7 @@
  * using png_read_png and then write with png_write_png.  Test all possible
  * transforms.
  */
+
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
@@ -317,11 +318,10 @@
 
    t &= -t; /* first set bit */
 
-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
-   {
-      if ((transform_info[i].transform & t) != 0)
-         return transform_info[i].name;
-   }
+   for (i=0; i<TTABLE_SIZE; ++i)
+      if (transform_info[i].name != NULL)
+         if ((transform_info[i].transform & t) != 0)
+            return transform_info[i].name;
 
    return "invalid transform";
 }
@@ -338,13 +338,16 @@
 {
    unsigned int i;
 
-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
    {
-      if (transform_info[i].when & TRANSFORM_R)
-         read_transforms |= transform_info[i].transform;
+      if (transform_info[i].name != NULL)
+      {
+         if (transform_info[i].when & TRANSFORM_R)
+            read_transforms |= transform_info[i].transform;
 
-      if (transform_info[i].when & TRANSFORM_W)
-         write_transforms |= transform_info[i].transform;
+         if (transform_info[i].when & TRANSFORM_W)
+            write_transforms |= transform_info[i].transform;
+      }
    }
 
    /* Reversible transforms are those which are supported on both read and
@@ -962,21 +965,24 @@
       int bd = dp->bit_depth;
       unsigned int i;
 
-      for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+      for (i=0; i<TTABLE_SIZE; ++i)
       {
-         int transform = transform_info[i].transform;
+         if (transform_info[i].name != NULL)
+         {
+            int transform = transform_info[i].transform;
 
-         if ((transform_info[i].valid_chunks == 0 ||
-               (transform_info[i].valid_chunks & chunks) != 0) &&
-            (transform_info[i].color_mask_required & ct) ==
-               transform_info[i].color_mask_required &&
-            (transform_info[i].color_mask_absent & ct) == 0 &&
-            (transform_info[i].bit_depths & bd) != 0 &&
-            (transform_info[i].when & TRANSFORM_R) != 0)
-            active |= transform;
+            if ((transform_info[i].valid_chunks == 0 ||
+                  (transform_info[i].valid_chunks & chunks) != 0) &&
+               (transform_info[i].color_mask_required & ct) ==
+                  transform_info[i].color_mask_required &&
+               (transform_info[i].color_mask_absent & ct) == 0 &&
+               (transform_info[i].bit_depths & bd) != 0 &&
+               (transform_info[i].when & TRANSFORM_R) != 0)
+               active |= transform;
 
-         else if ((transform_info[i].when & TRANSFORM_R) != 0)
-            inactive |= transform;
+            else if ((transform_info[i].when & TRANSFORM_R) != 0)
+               inactive |= transform;
+         }
       }
 
       /* Some transforms appear multiple times in the table; the 'active' status
@@ -1000,8 +1006,9 @@
    int interlace_method, compression_method, filter_method;
    const char *e = NULL;
 
-   png_get_IHDR(dp->read_pp, dp->read_ip, &width, &height, &bit_depth,
-      &color_type, &interlace_method, &compression_method, &filter_method);
+   if (!png_get_IHDR(dp->read_pp, dp->read_ip, &width, &height, &bit_depth,
+      &color_type, &interlace_method, &compression_method, &filter_method))
+      display_log(dp, LIBPNG_BUG, "png_get_IHDR failed");
 
 #  define C(item) if (item != dp->item) \
       display_log(dp, APP_WARNING, "IHDR " #item "(%lu) changed to %lu",\
@@ -1081,8 +1088,9 @@
                size_t x;
 
                /* Find the first error */
-               for (x=0; x<rowbytes-1; ++x) if (row[x] != orig[x])
-                  break;
+               for (x=0; x<rowbytes-1; ++x)
+                  if (row[x] != orig[x])
+                     break;
 
                display_log(dp, APP_FAIL,
                   "byte(%lu,%lu) changed 0x%.2x -> 0x%.2x",
@@ -1137,6 +1145,7 @@
                display_log(dp, LIBPNG_ERROR, "invalid colour type %d",
                   color_type);
                /*NOTREACHED*/
+               memset(sig_bits, 0, sizeof(sig_bits));
                bpp = 0;
                break;
          }
@@ -1198,7 +1207,7 @@
                sig_bits[0] = (png_byte)b;
                break;
 
-            case 4: /* Relicate twice */
+            case 4: /* Replicate twice */
                /* Value is 1, 2, 3 or 4 */
                b = 0xf & ((0xf << 4) >> sig_bits[0]);
                b |= b << 4;
@@ -1686,8 +1695,9 @@
 
                printf("%s: pngimage ", pass ? "PASS" : "FAIL");
 
-               for (j=1; j<option_end; ++j) if (j != ilog)
-                  printf("%s ", argv[j]);
+               for (j=1; j<option_end; ++j)
+                  if (j != ilog)
+                     printf("%s ", argv[j]);
 
                printf("%s\n", d.filename);
             }
diff --git a/contrib/libtests/pngstest.c b/contrib/libtests/pngstest.c
index a368bf0..cd4f3cd 100644
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -1,7 +1,7 @@
-/*-
- * pngstest.c
+
+/* pngstest.c
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2013-2017 John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -10,8 +10,9 @@
  *
  * Test for the PNG 'simplified' APIs.
  */
+
 #define _ISOC90_SOURCE 1
-#define MALLOC_CHECK_ 2/*glibc facility: turn on debugging*/
+#define MALLOC_CHECK_ 2 /*glibc facility: turn on debugging*/
 
 #include <stddef.h>
 #include <stdlib.h>
@@ -2701,7 +2702,7 @@
             {
                if ((a->opts & ACCUMULATE) == 0)
                {
-                  char pindex[9];
+                  char pindex[16];
                   sprintf(pindex, "%lu[%lu]", (unsigned long)y,
                      (unsigned long)a->image.colormap_entries);
                   logerror(a, a->file_name, ": bad pixel index: ", pindex);
@@ -2712,12 +2713,12 @@
             else if (y >= b->image.colormap_entries)
             {
                if ((b->opts & ACCUMULATE) == 0)
-                  {
-                  char pindex[9];
+               {
+                  char pindex[16];
                   sprintf(pindex, "%lu[%lu]", (unsigned long)y,
                      (unsigned long)b->image.colormap_entries);
                   logerror(b, b->file_name, ": bad pixel index: ", pindex);
-                  }
+               }
                result = 0;
             }
 
@@ -2820,8 +2821,11 @@
          bchannels = component_loc(bloc, formatb);
 
          /* Hence the btoa array. */
-         for (i=0; i<4; ++i) if (bloc[i] < 4)
-            btoa[bloc[i]] = aloc[i]; /* may be '4' for alpha */
+         for (i=0; i<4; ++i)
+         {
+            if (bloc[i] < 4)
+               btoa[bloc[i]] = aloc[i]; /* may be '4' for alpha */
+         }
 
          if (alpha_added)
             alpha_added = bloc[0]; /* location of alpha channel in image b */
@@ -3209,10 +3213,10 @@
    else if (image->opts & USE_FILE)
    {
 #ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
-      static int counter = 0;
+      static unsigned int counter = 0;
       char name[32];
 
-      sprintf(name, "%s%d.png", tmpf, ++counter);
+      sprintf(name, "%s%u.png", tmpf, ++counter);
 
       if (png_image_write_to_file(&image->image, name, convert_to_8bit,
          image->buffer+16, (png_int_32)image->stride, image->colormap))
diff --git a/contrib/libtests/pngunknown.c b/contrib/libtests/pngunknown.c
index 05bdd83..dfa9d10 100644
--- a/contrib/libtests/pngunknown.c
+++ b/contrib/libtests/pngunknown.c
@@ -1,7 +1,7 @@
 
 /* pngunknown.c - test the read side unknown chunk handling
  *
- * Last changed in libpng 1.6.32 [August 24, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2015,2017 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
@@ -370,7 +370,9 @@
 {
    int i = NINFO;
 
-   while (--i >= 0) if (chunk_info[i].flag == flag) return i;
+   while (--i >= 0)
+      if (chunk_info[i].flag == flag)
+         return i;
 
    fprintf(stderr, "pngunknown: internal error\n");
    exit(4);
@@ -547,27 +549,30 @@
 
       case PNG_HANDLE_CHUNK_AS_DEFAULT:
       case PNG_HANDLE_CHUNK_NEVER:
-         discard = 1/*handled; discard*/;
+         discard = 1; /*handled; discard*/
          break;
 
       case PNG_HANDLE_CHUNK_IF_SAFE:
       case PNG_HANDLE_CHUNK_ALWAYS:
-         discard = 0/*not handled; keep*/;
+         discard = 0; /*not handled; keep*/
          break;
    }
 
    /* Also store information about this chunk in the display, the relevant flag
     * is set if the chunk is to be kept ('not handled'.)
     */
-   if (chunk >= 0) if (!discard) /* stupidity to stop a GCC warning */
+   if (chunk >= 0)
    {
-      png_uint_32 flag = chunk_info[chunk].flag;
+      if (!discard) /* stupidity to stop a GCC warning */
+      {
+         png_uint_32 flag = chunk_info[chunk].flag;
 
-      if (pc->location & PNG_AFTER_IDAT)
-         d->after_IDAT |= flag;
+         if (pc->location & PNG_AFTER_IDAT)
+            d->after_IDAT |= flag;
 
-      else
-         d->before_IDAT |= flag;
+         else
+            d->before_IDAT |= flag;
+      }
    }
 
    /* However if there is no support to store unknown chunks don't ask libpng to
@@ -841,8 +846,9 @@
             {
                png_uint_32 y;
 
-               for (y=0; y<height; ++y) if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
-                  png_read_row(d->png_ptr, NULL, NULL);
+               for (y=0; y<height; ++y)
+                  if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
+                     png_read_row(d->png_ptr, NULL, NULL);
             }
          }
       } /* interlaced */
@@ -1091,15 +1097,15 @@
 
 static const char *standard_tests[] =
 {
- "discard", "default=discard", 0,
- "save", "default=save", 0,
- "if-safe", "default=if-safe", 0,
- "vpAg", "vpAg=if-safe", 0,
- "sTER", "sTER=if-safe", 0,
- "IDAT", "default=discard", "IDAT=save", 0,
- "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
-   "sBIT=save", "sRGB=save", "eXIf=save", 0,
- 0/*end*/
+   "discard", "default=discard", NULL,
+   "save", "default=save", NULL,
+   "if-safe", "default=if-safe", NULL,
+   "vpAg", "vpAg=if-safe", NULL,
+   "sTER", "sTER=if-safe", NULL,
+   "IDAT", "default=discard", "IDAT=save", NULL,
+   "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
+      "sBIT=save", "sRGB=save", "eXIf=save", NULL,
+   NULL /*end*/
 };
 
 static PNG_NORETURN void
@@ -1115,7 +1121,7 @@
 main(int argc, const char **argv)
 {
    FILE *fp;
-   png_uint_32 default_flags[4/*valid,unknown{before,after}*/];
+   png_uint_32 default_flags[4]; /*valid,unknown{before,after}*/
    int strict = 0, default_tests = 0;
    const char *count_argv = "default=save";
    const char *touch_file = NULL;
@@ -1153,8 +1159,9 @@
    /* GCC BUG: if (default_tests && argc != 1) triggers some weird GCC argc
     * optimization which causes warnings with -Wstrict-overflow!
     */
-   else if (default_tests) if (argc != 1)
-      usage(d.program, "extra arguments");
+   else if (default_tests)
+      if (argc != 1)
+         usage(d.program, "extra arguments");
 
    /* The name of the test file is the last argument; remove it. */
    d.file = argv[--argc];
@@ -1216,7 +1223,11 @@
          const char *result;
          int arg_count = 0;
 
-         while (*next) ++next, ++arg_count;
+         while (*next != NULL)
+         {
+            ++next;
+            ++arg_count;
+         }
 
          perform_one_test_safe(fp, arg_count, test, default_flags, &d,
             this_test);
diff --git a/contrib/libtests/pngvalid.c b/contrib/libtests/pngvalid.c
index d800110..49eed5c 100644
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
@@ -1,7 +1,7 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2014-2017 John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -22,6 +22,7 @@
 #define _ISOC99_SOURCE 1 /* For floating point */
 #define _GNU_SOURCE 1 /* For the floating point exception extension */
 #define _BSD_SOURCE 1 /* For the floating point exception extension */
+#define _DEFAULT_SOURCE 1 /* For the floating point exception extension */
 
 #include <signal.h>
 #include <stdio.h>
@@ -5822,8 +5823,9 @@
       for (interlace_type = PNG_INTERLACE_NONE;
            interlace_type < INTERLACE_LAST; ++interlace_type)
       {
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            interlace_type, 0, 0, 0), do_read_interlace, pm->use_update_info);
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+            0/*palette*/, interlace_type, 0, 0, 0), do_read_interlace,
+            pm->use_update_info);
 
          if (fail(pm))
             return 0;
@@ -5876,47 +5878,50 @@
    {
       png_uint_32 h, w;
 
-      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])
+      for (h=1; h<=16; h+=hinc[bdlo])
       {
-         /* First test all the 'size' images against the sequential
-          * reader using libpng to deinterlace (where required.)  This
-          * validates the write side of libpng.  There are four possibilities
-          * to validate.
-          */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,
-            pm->use_update_info);
+         for (w=1; w<=16; w+=winc[bdlo])
+         {
+            /* First test all the 'size' images against the sequential
+            * reader using libpng to deinterlace (where required.)  This
+            * validates the write side of libpng.  There are four possibilities
+            * to validate.
+            */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,
-            pm->use_update_info);
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-         /* Now validate the interlaced read side - do_interlace true,
-          * in the progressive case this does actually make a difference
-          * to the code used in the non-interlaced case too.
-          */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,
-            pm->use_update_info);
+            /* Now validate the interlaced read side - do_interlace true,
+            * in the progressive case this does actually make a difference
+            * to the code used in the non-interlaced case too.
+            */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-#     if CAN_WRITE_INTERLACE
-         /* Validate the pngvalid code itself: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 1), 1/*do_interlace*/,
-            pm->use_update_info);
+#        if CAN_WRITE_INTERLACE
+            /* Validate the pngvalid code itself: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 1), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
+            if (fail(pm))
+               return 0;
+#        endif
+         }
       }
    }
 
@@ -5927,45 +5932,48 @@
    {
       png_uint_32 h, w;
 
-      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])
+      for (h=1; h<=16; h+=hinc[bdlo])
       {
-#     ifdef PNG_READ_INTERLACING_SUPPORTED
-         /* Test with pngvalid generated interlaced images first; we have
-          * already verify these are ok (unless pngvalid has self-consistent
-          * read/write errors, which is unlikely), so this detects errors in the
-          * read side first:
-          */
-#     if CAN_WRITE_INTERLACE
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,
-            pm->use_update_info);
+         for (w=1; w<=16; w+=winc[bdlo])
+         {
+#        ifdef PNG_READ_INTERLACING_SUPPORTED
+            /* Test with pngvalid generated interlaced images first; we have
+            * already verify these are ok (unless pngvalid has self-consistent
+            * read/write errors, which is unlikely), so this detects errors in
+            * the read side first:
+            */
+#        if CAN_WRITE_INTERLACE
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
-#     endif /* READ_INTERLACING */
+            if (fail(pm))
+               return 0;
+#        endif
+#        endif /* READ_INTERLACING */
 
-#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
-         /* Test the libpng write side against the pngvalid read side: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
-            pm->use_update_info);
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            /* Test the libpng write side against the pngvalid read side: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
+            if (fail(pm))
+               return 0;
+#        endif
 
-#     ifdef PNG_READ_INTERLACING_SUPPORTED
-#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
-         /* Test both together: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
-            pm->use_update_info);
+#        ifdef PNG_READ_INTERLACING_SUPPORTED
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            /* Test both together: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
-#     endif /* READ_INTERLACING */
+            if (fail(pm))
+               return 0;
+#        endif
+#        endif /* READ_INTERLACING */
+         }
       }
    }
 
@@ -7635,7 +7643,7 @@
 
    else
    {
-      /* The default (built in) coeffcients, as above: */
+      /* The default (built in) coefficients, as above: */
 #     if PNG_LIBPNG_VER < 10700
          data.red_coefficient = 6968 / 32768.;
          data.green_coefficient = 23434 / 32768.;
@@ -10649,16 +10657,21 @@
    {
       unsigned int i, j;
 
-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
-         if (i != j)
+      for (i=0; i<pm->ngamma_tests; ++i)
+      {
+         for (j=0; j<pm->ngamma_tests; ++j)
          {
-            gamma_transform_test(pm, colour_type, bit_depth, palette_number,
-               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j], 0/*sBIT*/,
-               pm->use_input_precision, 0 /*do not scale16*/);
+            if (i != j)
+            {
+               gamma_transform_test(pm, colour_type, bit_depth, palette_number,
+                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+                  0/*sBIT*/, pm->use_input_precision, 0/*do not scale16*/);
 
-            if (fail(pm))
-               return;
+               if (fail(pm))
+                  return;
+            }
          }
+      }
    }
 }
 
@@ -10687,14 +10700,17 @@
          {
             unsigned int j;
 
-            for (j=0; j<pm->ngamma_tests; ++j) if (i != j)
+            for (j=0; j<pm->ngamma_tests; ++j)
             {
-               gamma_transform_test(pm, colour_type, bit_depth, npalette,
-                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
-                  sbit, pm->use_input_precision_sbit, 0 /*scale16*/);
+               if (i != j)
+               {
+                  gamma_transform_test(pm, colour_type, bit_depth, npalette,
+                     pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+                     sbit, pm->use_input_precision_sbit, 0 /*scale16*/);
 
-               if (fail(pm))
-                  return;
+                  if (fail(pm))
+                     return;
+               }
             }
          }
       }
@@ -10946,14 +10962,17 @@
       unsigned int i, j;
 
       /* Don't skip the i==j case here - it's relevant. */
-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
+      for (i=0; i<pm->ngamma_tests; ++i)
       {
-         gamma_composition_test(pm, colour_type, bit_depth, palette_number,
-            pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
-            pm->use_input_precision, do_background, expand_16);
+         for (j=0; j<pm->ngamma_tests; ++j)
+         {
+            gamma_composition_test(pm, colour_type, bit_depth, palette_number,
+               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+               pm->use_input_precision, do_background, expand_16);
 
-         if (fail(pm))
-            return;
+            if (fail(pm))
+               return;
+         }
       }
    }
 }
@@ -11056,7 +11075,7 @@
          pm->calculations_use_input_precision = 0;
 
       if (summary)
-         summarize_gamma_errors(pm, 0/*who*/, 1/*low bit depth*/, 1/*indexed*/);
+         summarize_gamma_errors(pm, NULL/*who*/, 1/*low bit depth*/, 1/*indexed*/);
 
       if (fail(pm))
          return;
@@ -11182,8 +11201,10 @@
 {
    int x, y;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
-      return y;
+   for (y=0; y<8; ++y)
+      for (x=0; x<8; ++x)
+         if (adam7[y][x] == pass)
+            return y;
    return 0xf;
 }
 
@@ -11192,8 +11213,10 @@
 {
    int x, y;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
-      return x;
+   for (x=0; x<8; ++x)
+      for (y=0; y<8; ++y)
+         if (adam7[y][x] == pass)
+            return x;
    return 0xf;
 }
 
@@ -11202,18 +11225,24 @@
 {
    int x, y, base=(-1), inc=8;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   for (y=0; y<8; ++y)
    {
-      if (base == (-1))
-         base = y;
-      else if (base == y)
-         {}
-      else if (inc == y-base)
-         base=y;
-      else if (inc == 8)
-         inc = y-base, base=y;
-      else if (inc != y-base)
-         return 0xff; /* error - more than one 'inc' value! */
+      for (x=0; x<8; ++x)
+      {
+         if (adam7[y][x] == pass)
+         {
+            if (base == (-1))
+               base = y;
+            else if (base == y)
+               {}
+            else if (inc == y-base)
+               base=y;
+            else if (inc == 8)
+               inc = y-base, base=y;
+            else if (inc != y-base)
+               return 0xff; /* error - more than one 'inc' value! */
+         }
+      }
    }
 
    if (base == (-1)) return 0xfe; /* error - no row in pass! */
@@ -11236,18 +11265,24 @@
 {
    int x, y, base=(-1), inc=8;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   for (x=0; x<8; ++x)
    {
-      if (base == (-1))
-         base = x;
-      else if (base == x)
-         {}
-      else if (inc == x-base)
-         base=x;
-      else if (inc == 8)
-         inc = x-base, base=x;
-      else if (inc != x-base)
-         return 0xff; /* error - more than one 'inc' value! */
+      for (y=0; y<8; ++y)
+      {
+         if (adam7[y][x] == pass)
+         {
+            if (base == (-1))
+               base = x;
+            else if (base == x)
+               {}
+            else if (inc == x-base)
+               base=x;
+            else if (inc == 8)
+               inc = x-base, base=x;
+            else if (inc != x-base)
+               return 0xff; /* error - more than one 'inc' value! */
+         }
+      }
    }
 
    if (base == (-1)) return 0xfe; /* error - no row in pass! */
@@ -11311,8 +11346,9 @@
    int x;
    y &= 7;
    ++pass;
-   for (x=0; x<8; ++x) if (adam7[y][x] == pass)
-      return 1;
+   for (x=0; x<8; ++x)
+      if (adam7[y][x] == pass)
+         return 1;
 
    return 0;
 }
@@ -11324,8 +11360,9 @@
    int y;
    x &= 7;
    ++pass;
-   for (y=0; y<8; ++y) if (adam7[y][x] == pass)
-      return 1;
+   for (y=0; y<8; ++y)
+      if (adam7[y][x] == pass)
+         return 1;
 
    return 0;
 }
@@ -11339,11 +11376,17 @@
 
    height &= 7;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   for (y=0; y<8; ++y)
    {
-      rows += tiles;
-      if (y < height) ++rows;
-      break; /* i.e. break the 'x', column, loop. */
+      for (x=0; x<8; ++x)
+      {
+         if (adam7[y][x] == pass)
+         {
+            rows += tiles;
+            if (y < height) ++rows;
+            break; /* i.e. break the 'x', column, loop. */
+         }
+      }
    }
 
    return rows;
@@ -11358,11 +11401,17 @@
 
    width &= 7;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   for (x=0; x<8; ++x)
    {
-      cols += tiles;
-      if (x < width) ++cols;
-      break; /* i.e. break the 'y', row, loop. */
+      for (y=0; y<8; ++y)
+      {
+         if (adam7[y][x] == pass)
+         {
+            cols += tiles;
+            if (x < width) ++cols;
+            break; /* i.e. break the 'y', row, loop. */
+         }
+      }
    }
 
    return cols;
@@ -11719,7 +11768,7 @@
 
    /* The following allows results to pass if they correspond to anything in the
     * transformed range [input-.5,input+.5]; this is is required because of the
-    * way libpng treates the 16_TO_8 flag when building the gamma tables in
+    * way libpng treats the 16_TO_8 flag when building the gamma tables in
     * releases up to 1.6.0.
     *
     * TODO: review this
@@ -11810,21 +11859,21 @@
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
       else if (strncmp(*argv, "--transform-disable=",
          sizeof "--transform-disable") == 0)
-         {
+      {
          pm.test_transform = 1;
          transform_disable(*argv + sizeof "--transform-disable");
-         }
+      }
 
       else if (strncmp(*argv, "--transform-enable=",
          sizeof "--transform-enable") == 0)
-         {
+      {
          pm.test_transform = 1;
          transform_enable(*argv + sizeof "--transform-enable");
-         }
+      }
 #endif /* PNG_READ_TRANSFORMS_SUPPORTED */
 
       else if (strcmp(*argv, "--gamma") == 0)
-         {
+      {
          /* Just do two gamma tests here (2.2 and linear) for speed: */
          pm.ngamma_tests = 2U;
          pm.test_gamma_threshold = 1;
@@ -11833,7 +11882,7 @@
          pm.test_gamma_scale16 = 1;
          pm.test_gamma_background = 1; /* composition */
          pm.test_gamma_alpha_mode = 1;
-         }
+      }
 
       else if (strcmp(*argv, "--nogamma") == 0)
          pm.ngamma_tests = 0;
diff --git a/contrib/libtests/readpng.c b/contrib/libtests/readpng.c
index 60a2d46..7528e90 100644
--- a/contrib/libtests/readpng.c
+++ b/contrib/libtests/readpng.c
@@ -1,9 +1,8 @@
+
 /* readpng.c
  *
  * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.1 [March 28, 2013]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
diff --git a/contrib/libtests/tarith.c b/contrib/libtests/tarith.c
index c03f05a..ead77e9 100644
--- a/contrib/libtests/tarith.c
+++ b/contrib/libtests/tarith.c
@@ -1,10 +1,9 @@
 
 /* tarith.c
  *
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2011-2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [February 14, 2013]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -88,6 +87,7 @@
    int    minorarith = 0;
 
    while (--argc > 0)
+   {
       if (strcmp(*++argv, "-a") == 0)
          showall = 1;
       else if (strcmp(*argv, "-e") == 0 && argc > 0)
@@ -105,6 +105,7 @@
          fprintf(stderr, "unknown argument %s\n", *argv);
          return 1;
       }
+   }
 
    do
    {
@@ -130,8 +131,8 @@
        */
       if (buffer[precision+7] != 71)
       {
-         fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test,
-            precision, buffer, (unsigned long)strlen(buffer));
+         fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n",
+            test, precision, buffer, (unsigned long)strlen(buffer));
          failed = 1;
       }
 
@@ -146,16 +147,16 @@
          if (test >= 0 && strcmp(buffer, "inf") ||
              test <  0 && strcmp(buffer, "-inf"))
          {
-            fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test,
-               precision, buffer);
+            fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n",
+               test, precision, buffer);
             failed = 1;
          }
       }
       else if (!png_check_fp_number(buffer, precision+10, &state, &index) ||
           buffer[index] != 0)
       {
-         fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test,
-         precision, buffer, buffer[index]);
+         fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n",
+            test, precision, buffer, buffer[index]);
          failed = 1;
       }
       else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0))
@@ -187,7 +188,7 @@
          /* Check the result against the original. */
          double out = atof(buffer);
          double change = fabs((out - test)/test);
-         double allow = .5/pow(10,
+         double allow = .5 / pow(10,
             (precision >= DBL_DIG) ? DBL_DIG-1 : precision-1);
 
          /* NOTE: if you hit this error case are you compiling with gcc
@@ -257,8 +258,9 @@
    }
    while (--count);
 
-   printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor "
-      "arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith);
+   printf("Tested %d finite values, %d non-finite, %d OK (%d failed) "
+      "%d minor arithmetic errors\n",
+      finite, nonfinite, ok, failcount, minorarith);
    printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs);
    printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max);
 
@@ -371,8 +373,8 @@
    /* This should never fail (it's a serious bug if it does): */
    if (index != 0 && index != 1)
    {
-      fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number,
-         (unsigned long)index);
+      fprintf(stderr, "%s: read beyond end of string (%lu)\n",
+         co->number, (unsigned long)index);
       return 0;
    }
 
@@ -503,8 +505,8 @@
       if (number_is_valid != c.number_was_valid)
       {
          fprintf(stderr,
-            "%s: character '%c' [0x%.2x] changed number validity\n", co->number,
-            ch, ch);
+            "%s: character '%c' [0x%.2x] changed number validity\n",
+            co->number, ch, ch);
          return 0;
       }
 
@@ -521,10 +523,13 @@
 {
    int ch;
 
-   if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch)
+   if (c.cnumber+4 < sizeof co->number)
    {
-      if (!check_one_character(co, c, ch))
-         return 0;
+      for (ch=0; ch<256; ++ch)
+      {
+         if (!check_one_character(co, c, ch))
+            return 0;
+      }
    }
 
    return 1;
@@ -539,10 +544,13 @@
 
    if (c.cnumber+4 < sizeof co->number && c.limit >= 0)
    {
-      if (c.limit > 0) for (i=0; tests[i]; ++i)
+      if (c.limit > 0)
       {
-         if (!check_one_character(co, c, tests[i]))
-               return 0;
+         for (i=0; tests[i]; ++i)
+         {
+            if (!check_one_character(co, c, tests[i]))
+                  return 0;
+         }
       }
 
       /* At the end check all the characters. */
@@ -616,10 +624,10 @@
    png_int_32 times, div;
 
    while (--argc > 0)
-      {
-         fprintf(stderr, "unknown argument %s\n", *++argv);
-         return 1;
-      }
+   {
+      fprintf(stderr, "unknown argument %s\n", *++argv);
+      return 1;
+   }
 
    /* Find out about the random number generator. */
    randbuffer = RAND_MAX;
@@ -687,25 +695,25 @@
         ok = 0, ++overflow, fpround = fp/*misleading*/;
 
       if (verbose)
-         fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div,
-            fp, ok ? "ok" : "overflow");
+         fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n",
+            a, times, div, fp, ok ? "ok" : "overflow");
 
       ++tested;
       if (png_muldiv(&result, a, times, div) != ok)
       {
          ++error;
          if (ok)
-             fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a,
-                times, div, fp);
+             fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n",
+                a, times, div, fp);
          else
-             fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a,
-                times, div, result, fp);
+             fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n",
+                a, times, div, result, fp);
       }
       else if (ok && result != fpround)
       {
          ++error;
-         fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result,
-            fp);
+         fprintf(stderr, "%d * %d / %d -> %d not %lld\n",
+            a, times, div, result, fp);
       }
       else
          ++passed;
@@ -721,8 +729,8 @@
    }
    while (--count > 0);
 
-   printf("%d tests including %d overflows, %d passed, %d failed (%d 64-bit "
-      "errors)\n", tested, overflow, passed, error, error64);
+   printf("%d tests including %d overflows, %d passed, %d failed "
+      "(%d 64-bit errors)\n", tested, overflow, passed, error, error64);
    return 0;
 }
 
@@ -821,8 +829,9 @@
          {
             if (error > .68) /* By experiment error is less than .68 */
             {
-               fprintf(stderr, "16-bit log error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_log16bit(i), correct, error);
+               fprintf(stderr,
+                  "16-bit log error: %d: got %u, expected %f error: %f\n",
+                  i, png_log16bit(i), correct, error);
             }
          }
       }
@@ -841,8 +850,9 @@
             maxerr = fabs(error);
          if (fabs(error) > 1883) /* By experiment. */
          {
-            fprintf(stderr, "32-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp(i), correct, error);
+            fprintf(stderr,
+               "32-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp(i), correct, error);
          }
       }
 
@@ -859,8 +869,9 @@
             maxerr = fabs(error);
          if (fabs(error) > .50002) /* By experiment */
          {
-            fprintf(stderr, "8-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp8bit(i), correct, error);
+            fprintf(stderr,
+               "8-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp8bit(i), correct, error);
          }
       }
 
@@ -877,8 +888,9 @@
             maxerr = fabs(error);
          if (fabs(error) > .524) /* By experiment */
          {
-            fprintf(stderr, "16-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp16bit(i), correct, error);
+            fprintf(stderr,
+               "16-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp16bit(i), correct, error);
          }
       }
 
diff --git a/contrib/libtests/timepng.c b/contrib/libtests/timepng.c
index 23d8b17..0093a45 100644
--- a/contrib/libtests/timepng.c
+++ b/contrib/libtests/timepng.c
@@ -1,9 +1,8 @@
+
 /* timepng.c
  *
  * Copyright (c) 2013,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.22 [May 26, 2016]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -528,7 +527,7 @@
       }
    }
 
-   else if (nfiles == 0) /* Read from stdin withoout --dissemble */
+   else if (nfiles == 0) /* Read from stdin without --dissemble */
    {
       char filename[FILENAME_MAX+1];
 
diff --git a/contrib/mips-msa/linux.c b/contrib/mips-msa/linux.c
index 140215c..3bac611 100644
--- a/contrib/mips-msa/linux.c
+++ b/contrib/mips-msa/linux.c
@@ -1,8 +1,9 @@
+
 /* contrib/mips-msa/linux.c
  *
+ * Copyright (c) 2020 Cosmin Truta
  * Copyright (c) 2016 Glenn Randers-Pehrson
  * Written by Mandar Sahastrabuddhe, 2016.
- * Last changed in libpng 1.6.25beta03 [August 29, 2016]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -47,8 +48,10 @@
 
          int val = strcmp(string, word);
 
-         if (val == 0)
+         if (val == 0) {
+            fclose(f);
             return 1;
+         }
 
          i = 0;
          memset(word, 0, 10);
diff --git a/contrib/oss-fuzz/libpng_read_fuzzer.cc b/contrib/oss-fuzz/libpng_read_fuzzer.cc
index 7b30550..2064a84 100644
--- a/contrib/oss-fuzz/libpng_read_fuzzer.cc
+++ b/contrib/oss-fuzz/libpng_read_fuzzer.cc
@@ -78,6 +78,22 @@
   buf_state->data += length;
 }
 
+void* limited_malloc(png_structp, png_alloc_size_t size) {
+  // libpng may allocate large amounts of memory that the fuzzer reports as
+  // an error. In order to silence these errors, make libpng fail when trying
+  // to allocate a large amount. This allocator used to be in the Chromium
+  // version of this fuzzer.
+  // This number is chosen to match the default png_user_chunk_malloc_max.
+  if (size > 8000000)
+    return nullptr;
+
+  return malloc(size);
+}
+
+void default_free(png_structp, png_voidp ptr) {
+  return free(ptr);
+}
+
 static const int kPngHeaderSize = 8;
 
 // Entry point for LibFuzzer.
@@ -118,6 +134,9 @@
     return 0;
   }
 
+  // Use a custom allocator that fails for large allocations to avoid OOM.
+  png_set_mem_fn(png_handler.png_ptr, nullptr, limited_malloc, default_free);
+
   png_set_crc_action(png_handler.png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE);
 #ifdef PNG_IGNORE_ADLER32
   png_set_option(png_handler.png_ptr, PNG_IGNORE_ADLER32, PNG_OPTION_ON);
diff --git a/contrib/tools/genpng.c b/contrib/tools/genpng.c
index 0b3f981..3140fb4 100644
--- a/contrib/tools/genpng.c
+++ b/contrib/tools/genpng.c
@@ -453,7 +453,7 @@
  * { inside_circle_filled, check_circle_filled },
  * { inside_circle, check_circle }
  *
- * The functions here are analoguous to the square ones; however, they check
+ * The functions here are analogous to the square ones; however, they check
  * the corresponding ellipse as opposed to the rectangle.
  */
 static int
diff --git a/contrib/tools/pngcp.c b/contrib/tools/pngcp.c
index 16d4e7f..c03b6c7 100644
--- a/contrib/tools/pngcp.c
+++ b/contrib/tools/pngcp.c
@@ -336,7 +336,7 @@
 #  define VLC(name) VLCIDAT(name) VLCiCCP(name) VLCzTXt(name)
 
 #  ifdef PNG_SW_COMPRESS_png_level
-      /* The libpng compression level isn't searched because it justs sets the
+      /* The libpng compression level isn't searched because it just sets the
        * other things that are searched!
        */
       VLO("compression", compression, 0)
diff --git a/contrib/tools/pngfix.c b/contrib/tools/pngfix.c
index 2fa5d13..389434f 100644
--- a/contrib/tools/pngfix.c
+++ b/contrib/tools/pngfix.c
@@ -1598,7 +1598,7 @@
    chunk->chunk_length = file->length;
    chunk->chunk_type = file->type;
 
-   /* Compresssed/uncompressed size information (from the zlib control structure
+   /* Compressed/uncompressed size information (from the zlib control structure
     * that is used to check the compressed data in a chunk.)
     */
    chunk->uncompressed_digits = 0;
@@ -2929,7 +2929,7 @@
    }
 
    /* Control reaches this point if the chunk must be skipped.  For chunks other
-    * than IDAT this means that the zlib compressed data is fatally damanged and
+    * than IDAT this means that the zlib compressed data is fatally damaged and
     * the chunk will not be passed to libpng.  For IDAT it means that the end of
     * the IDAT stream has not yet been reached and we must handle the next
     * (IDAT) chunk.  If the LZ data in an IDAT stream cannot be read 'stop' must
diff --git a/depcomp b/depcomp
index 65cbf70..715e343 100755
--- a/depcomp
+++ b/depcomp
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
diff --git a/example.c b/example.c
index 2e2afaa..b3038ef 100644
--- a/example.c
+++ b/example.c
@@ -125,6 +125,7 @@
                png_image_free(&image);
             else
                free(buffer);
+         }
       }
 
       /* Something went wrong reading or writing the image.  libpng stores a
diff --git a/install-sh b/install-sh
index 8175c64..ec298b5 100755
--- a/install-sh
+++ b/install-sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 # install - install a program, script, or datafile
 
-scriptversion=2018-03-11.20; # UTC
+scriptversion=2020-11-14.01; # UTC
 
 # This originates from X11R5 (mit/util/scripts/install.sh), which was
 # later released in X11R6 (xc/config/util/install.sh) with the
@@ -69,6 +69,11 @@
 # Desired mode of installed file.
 mode=0755
 
+# Create dirs (including intermediate dirs) using mode 755.
+# This is like GNU 'install' as of coreutils 8.32 (2020).
+mkdir_umask=22
+
+backupsuffix=
 chgrpcmd=
 chmodcmd=$chmodprog
 chowncmd=
@@ -99,18 +104,28 @@
      --version  display version info and exit.
 
   -c            (ignored)
-  -C            install only if different (preserve the last data modification time)
+  -C            install only if different (preserve data modification time)
   -d            create directories instead of installing files.
   -g GROUP      $chgrpprog installed files to GROUP.
   -m MODE       $chmodprog installed files to MODE.
   -o USER       $chownprog installed files to USER.
+  -p            pass -p to $cpprog.
   -s            $stripprog installed files.
+  -S SUFFIX     attempt to back up existing files, with suffix SUFFIX.
   -t DIRECTORY  install into DIRECTORY.
   -T            report an error if DSTFILE is a directory.
 
 Environment variables override the default commands:
   CHGRPPROG CHMODPROG CHOWNPROG CMPPROG CPPROG MKDIRPROG MVPROG
   RMPROG STRIPPROG
+
+By default, rm is invoked with -f; when overridden with RMPROG,
+it's up to you to specify -f if you want it.
+
+If -S is not specified, no backups are attempted.
+
+Email bug reports to bug-automake@gnu.org.
+Automake home page: https://www.gnu.org/software/automake/
 "
 
 while test $# -ne 0; do
@@ -137,8 +152,13 @@
     -o) chowncmd="$chownprog $2"
         shift;;
 
+    -p) cpprog="$cpprog -p";;
+
     -s) stripcmd=$stripprog;;
 
+    -S) backupsuffix="$2"
+        shift;;
+
     -t)
         is_target_a_directory=always
         dst_arg=$2
@@ -255,6 +275,10 @@
     dstdir=$dst
     test -d "$dstdir"
     dstdir_status=$?
+    # Don't chown directories that already exist.
+    if test $dstdir_status = 0; then
+      chowncmd=""
+    fi
   else
 
     # Waiting for this to be detected by the "$cpprog $src $dsttmp" command
@@ -301,22 +325,6 @@
   if test $dstdir_status != 0; then
     case $posix_mkdir in
       '')
-        # Create intermediate dirs using mode 755 as modified by the umask.
-        # This is like FreeBSD 'install' as of 1997-10-28.
-        umask=`umask`
-        case $stripcmd.$umask in
-          # Optimize common cases.
-          *[2367][2367]) mkdir_umask=$umask;;
-          .*0[02][02] | .[02][02] | .[02]) mkdir_umask=22;;
-
-          *[0-7])
-            mkdir_umask=`expr $umask + 22 \
-              - $umask % 100 % 40 + $umask % 20 \
-              - $umask % 10 % 4 + $umask % 2
-            `;;
-          *) mkdir_umask=$umask,go-w;;
-        esac
-
         # With -d, create the new directory with the user-specified mode.
         # Otherwise, rely on $mkdir_umask.
         if test -n "$dir_arg"; then
@@ -326,52 +334,49 @@
         fi
 
         posix_mkdir=false
-        case $umask in
-          *[123567][0-7][0-7])
-            # POSIX mkdir -p sets u+wx bits regardless of umask, which
-            # is incompatible with FreeBSD 'install' when (umask & 300) != 0.
-            ;;
-          *)
-            # Note that $RANDOM variable is not portable (e.g. dash);  Use it
-            # here however when possible just to lower collision chance.
-            tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$
+	# The $RANDOM variable is not portable (e.g., dash).  Use it
+	# here however when possible just to lower collision chance.
+	tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$
 
-            trap 'ret=$?; rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir" 2>/dev/null; exit $ret' 0
+	trap '
+	  ret=$?
+	  rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir" 2>/dev/null
+	  exit $ret
+	' 0
 
-            # Because "mkdir -p" follows existing symlinks and we likely work
-            # directly in world-writeable /tmp, make sure that the '$tmpdir'
-            # directory is successfully created first before we actually test
-            # 'mkdir -p' feature.
-            if (umask $mkdir_umask &&
-                $mkdirprog $mkdir_mode "$tmpdir" &&
-                exec $mkdirprog $mkdir_mode -p -- "$tmpdir/a/b") >/dev/null 2>&1
-            then
-              if test -z "$dir_arg" || {
-                   # Check for POSIX incompatibilities with -m.
-                   # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
-                   # other-writable bit of parent directory when it shouldn't.
-                   # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
-                   test_tmpdir="$tmpdir/a"
-                   ls_ld_tmpdir=`ls -ld "$test_tmpdir"`
-                   case $ls_ld_tmpdir in
-                     d????-?r-*) different_mode=700;;
-                     d????-?--*) different_mode=755;;
-                     *) false;;
-                   esac &&
-                   $mkdirprog -m$different_mode -p -- "$test_tmpdir" && {
-                     ls_ld_tmpdir_1=`ls -ld "$test_tmpdir"`
-                     test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
-                   }
-                 }
-              then posix_mkdir=:
-              fi
-              rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir"
-            else
-              # Remove any dirs left behind by ancient mkdir implementations.
-              rmdir ./$mkdir_mode ./-p ./-- "$tmpdir" 2>/dev/null
-            fi
-            trap '' 0;;
-        esac;;
+	# Because "mkdir -p" follows existing symlinks and we likely work
+	# directly in world-writeable /tmp, make sure that the '$tmpdir'
+	# directory is successfully created first before we actually test
+	# 'mkdir -p'.
+	if (umask $mkdir_umask &&
+	    $mkdirprog $mkdir_mode "$tmpdir" &&
+	    exec $mkdirprog $mkdir_mode -p -- "$tmpdir/a/b") >/dev/null 2>&1
+	then
+	  if test -z "$dir_arg" || {
+	       # Check for POSIX incompatibilities with -m.
+	       # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
+	       # other-writable bit of parent directory when it shouldn't.
+	       # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
+	       test_tmpdir="$tmpdir/a"
+	       ls_ld_tmpdir=`ls -ld "$test_tmpdir"`
+	       case $ls_ld_tmpdir in
+		 d????-?r-*) different_mode=700;;
+		 d????-?--*) different_mode=755;;
+		 *) false;;
+	       esac &&
+	       $mkdirprog -m$different_mode -p -- "$test_tmpdir" && {
+		 ls_ld_tmpdir_1=`ls -ld "$test_tmpdir"`
+		 test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
+	       }
+	     }
+	  then posix_mkdir=:
+	  fi
+	  rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir"
+	else
+	  # Remove any dirs left behind by ancient mkdir implementations.
+	  rmdir ./$mkdir_mode ./-p ./-- "$tmpdir" 2>/dev/null
+	fi
+	trap '' 0;;
     esac
 
     if
@@ -382,7 +387,7 @@
     then :
     else
 
-      # The umask is ridiculous, or mkdir does not conform to POSIX,
+      # mkdir does not conform to POSIX,
       # or it failed possibly due to a race condition.  Create the
       # directory the slow way, step by step, checking for races as we go.
 
@@ -411,7 +416,7 @@
           prefixes=
         else
           if $posix_mkdir; then
-            (umask=$mkdir_umask &&
+            (umask $mkdir_umask &&
              $doit_exec $mkdirprog $mkdir_mode -p -- "$dstdir") && break
             # Don't fail if two instances are running concurrently.
             test -d "$prefix" || exit 1
@@ -451,7 +456,18 @@
     trap 'ret=$?; rm -f "$dsttmp" "$rmtmp" && exit $ret' 0
 
     # Copy the file name to the temp name.
-    (umask $cp_umask && $doit_exec $cpprog "$src" "$dsttmp") &&
+    (umask $cp_umask &&
+     { test -z "$stripcmd" || {
+	 # Create $dsttmp read-write so that cp doesn't create it read-only,
+	 # which would cause strip to fail.
+	 if test -z "$doit"; then
+	   : >"$dsttmp" # No need to fork-exec 'touch'.
+	 else
+	   $doit touch "$dsttmp"
+	 fi
+       }
+     } &&
+     $doit_exec $cpprog "$src" "$dsttmp") &&
 
     # and set any options; do chmod last to preserve setuid bits.
     #
@@ -477,6 +493,13 @@
     then
       rm -f "$dsttmp"
     else
+      # If $backupsuffix is set, and the file being installed
+      # already exists, attempt a backup.  Don't worry if it fails,
+      # e.g., if mv doesn't support -f.
+      if test -n "$backupsuffix" && test -f "$dst"; then
+        $doit $mvcmd -f "$dst" "$dst$backupsuffix" 2>/dev/null
+      fi
+
       # Rename the file to the real destination.
       $doit $mvcmd -f "$dsttmp" "$dst" 2>/dev/null ||
 
@@ -491,9 +514,9 @@
         # file should still install successfully.
         {
           test ! -f "$dst" ||
-          $doit $rmcmd -f "$dst" 2>/dev/null ||
+          $doit $rmcmd "$dst" 2>/dev/null ||
           { $doit $mvcmd -f "$dst" "$rmtmp" 2>/dev/null &&
-            { $doit $rmcmd -f "$rmtmp" 2>/dev/null; :; }
+            { $doit $rmcmd "$rmtmp" 2>/dev/null; :; }
           } ||
           { echo "$0: cannot unlink or rename $dst" >&2
             (exit 1); exit 1
diff --git a/libpng-manual.txt b/libpng-manual.txt
index 5dad92f..19b1e0c 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2022 Cosmin Truta
  Copyright (c) 1998-2018 Glenn Randers-Pehrson
 
  This document is released under the libpng license.
@@ -9,9 +9,9 @@
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.37 - April 2019
+ libpng version 1.6.36, December 2018, through 1.6.38 - September 2022
  Updated and distributed by Cosmin Truta
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2022 Cosmin Truta
 
  libpng versions 0.97, January 1998, through 1.6.35 - July 2018
  Updated and distributed by Glenn Randers-Pehrson
@@ -1792,7 +1792,7 @@
 version with no alpha channel use png_set_background; see below.
 
 As of libpng version 1.5.2, almost all useful expansions are supported, the
-major ommissions are conversion of grayscale to indexed images (which can be
+major omissions are conversion of grayscale to indexed images (which can be
 done trivially in the application) and conversion of indexed to grayscale (which
 can be done by a trivial manipulation of the palette.)
 
diff --git a/libpng.3 b/libpng.3
index f374235..b7fc182 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "April 14, 2019"
+.TH LIBPNG 3 "September 14, 2022"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.37
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.38
 
 .SH SYNOPSIS
 \fB#include <png.h>\fP
@@ -519,7 +519,7 @@
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2022 Cosmin Truta
  Copyright (c) 1998-2018 Glenn Randers-Pehrson
 
  This document is released under the libpng license.
@@ -528,9 +528,9 @@
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.37 - April 2019
+ libpng version 1.6.36, December 2018, through 1.6.38 - September 2022
  Updated and distributed by Cosmin Truta
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2022 Cosmin Truta
 
  libpng versions 0.97, January 1998, through 1.6.35 - July 2018
  Updated and distributed by Glenn Randers-Pehrson
@@ -2311,7 +2311,7 @@
 version with no alpha channel use png_set_background; see below.
 
 As of libpng version 1.5.2, almost all useful expansions are supported, the
-major ommissions are conversion of grayscale to indexed images (which can be
+major omissions are conversion of grayscale to indexed images (which can be
 done trivially in the application) and conversion of indexed to grayscale (which
 can be done by a trivial manipulation of the palette.)
 
diff --git a/libpng.pc.in b/libpng.pc.in
index 9708e9a..de127d4 100644
--- a/libpng.pc.in
+++ b/libpng.pc.in
@@ -6,7 +6,7 @@
 Name: libpng
 Description: Loads and saves PNG files
 Version: @PNGLIB_VERSION@
-Requires: zlib
+Requires.private: zlib
 Libs: -L${libdir} -lpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 Libs.private: @LIBS@
 Cflags: -I${includedir}
diff --git a/libpngpf.3 b/libpngpf.3
index 6909c70..3da3b86 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "April 14, 2019"
+.TH LIBPNGPF 3 "September 14, 2022"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.37
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.38
 (private functions)
 
 .SH SYNOPSIS
diff --git a/ltmain.sh b/ltmain.sh
index 0f0a2da..2a50d7f 100755
--- a/ltmain.sh
+++ b/ltmain.sh
@@ -1,12 +1,12 @@
-#! /bin/sh
+#! /usr/bin/env sh
 ## DO NOT EDIT - This file generated from ./build-aux/ltmain.in
-##               by inline-source v2014-01-03.01
+##               by inline-source v2019-02-19.15
 
-# libtool (GNU libtool) 2.4.6
+# libtool (GNU libtool) 2.4.7
 # Provide generalized library-building support services.
 # Written by Gordon Matzigkeit <gord@gnu.ai.mit.edu>, 1996
 
-# Copyright (C) 1996-2015 Free Software Foundation, Inc.
+# Copyright (C) 1996-2019, 2021-2022 Free Software Foundation, Inc.
 # This is free software; see the source for copying conditions.  There is NO
 # warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
@@ -31,8 +31,8 @@
 
 PROGRAM=libtool
 PACKAGE=libtool
-VERSION=2.4.6
-package_revision=2.4.6
+VERSION=2.4.7
+package_revision=2.4.7
 
 
 ## ------ ##
@@ -64,34 +64,25 @@
 # libraries, which are installed to $pkgauxdir.
 
 # Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2019-02-19.15; # UTC
 
 # General shell script boiler plate, and helper functions.
 # Written by Gary V. Vaughan, 2004
 
-# Copyright (C) 2004-2015 Free Software Foundation, Inc.
-# This is free software; see the source for copying conditions.  There is NO
-# warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# This is free software.  There is NO warranty; not even for
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Copyright (C) 2004-2019, 2021 Bootstrap Authors
+#
+# This file is dual licensed under the terms of the MIT license
+# <https://opensource.org/license/MIT>, and GPL version 2 or later
+# <http://www.gnu.org/licenses/gpl-2.0.html>.  You must apply one of
+# these licenses when using or redistributing this software or any of
+# the files within it.  See the URLs above, or the file `LICENSE`
+# included in the Bootstrap distribution for the full license texts.
 
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
-# (at your option) any later version.
-
-# As a special exception to the GNU General Public License, if you distribute
-# this file as part of a program or library that is built using GNU Libtool,
-# you may include this file under the same distribution terms that you use
-# for the rest of that program.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNES FOR A PARTICULAR PURPOSE. See the GNU
-# General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program. If not, see <http://www.gnu.org/licenses/>.
-
-# Please report bugs or propose patches to gary@gnu.org.
+# Please report bugs or propose patches to:
+# <https://github.com/gnulib-modules/bootstrap/issues>
 
 
 ## ------ ##
@@ -139,9 +130,12 @@
 	  _G_safe_locale=\"$_G_var=C; \$_G_safe_locale\"
 	fi"
 done
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
+# These NLS vars are set unconditionally (bootstrap issue #24).  Unset those
+# in case the environment reset is needed later and the $save_* variant is not
+# defined (see the code above).
+LC_ALL=C
+LANGUAGE=C
+export LANGUAGE LC_ALL
 
 # Make sure IFS has a sensible default
 sp=' '
@@ -159,6 +153,26 @@
 fi
 
 
+# func_unset VAR
+# --------------
+# Portably unset VAR.
+# In some shells, an 'unset VAR' statement leaves a non-zero return
+# status if VAR is already unset, which might be problematic if the
+# statement is used at the end of a function (thus poisoning its return
+# value) or when 'set -e' is active (causing even a spurious abort of
+# the script in this case).
+func_unset ()
+{
+    { eval $1=; (eval unset $1) >/dev/null 2>&1 && eval unset $1 || : ; }
+}
+
+
+# Make sure CDPATH doesn't cause `cd` commands to output the target dir.
+func_unset CDPATH
+
+# Make sure ${,E,F}GREP behave sanely.
+func_unset GREP_OPTIONS
+
 
 ## ------------------------- ##
 ## Locate command utilities. ##
@@ -259,7 +273,7 @@
     rm -f conftest.in conftest.tmp conftest.nl conftest.out
   }
 
-  func_path_progs "sed gsed" func_check_prog_sed $PATH:/usr/xpg4/bin
+  func_path_progs "sed gsed" func_check_prog_sed "$PATH:/usr/xpg4/bin"
   rm -f conftest.sed
   SED=$func_path_progs_result
 }
@@ -295,7 +309,7 @@
     rm -f conftest.in conftest.tmp conftest.nl conftest.out
   }
 
-  func_path_progs "grep ggrep" func_check_prog_grep $PATH:/usr/xpg4/bin
+  func_path_progs "grep ggrep" func_check_prog_grep "$PATH:/usr/xpg4/bin"
   GREP=$func_path_progs_result
 }
 
@@ -360,6 +374,35 @@
   s/\\([^$_G_bs]\\)$_G_bs2$_G_dollar/\\1$_G_bs2$_G_bs$_G_dollar/g
   s/\n//g"
 
+# require_check_ifs_backslash
+# ---------------------------
+# Check if we can use backslash as IFS='\' separator, and set
+# $check_ifs_backshlash_broken to ':' or 'false'.
+require_check_ifs_backslash=func_require_check_ifs_backslash
+func_require_check_ifs_backslash ()
+{
+  _G_save_IFS=$IFS
+  IFS='\'
+  _G_check_ifs_backshlash='a\\b'
+  for _G_i in $_G_check_ifs_backshlash
+  do
+  case $_G_i in
+  a)
+    check_ifs_backshlash_broken=false
+    ;;
+  '')
+    break
+    ;;
+  *)
+    check_ifs_backshlash_broken=:
+    break
+    ;;
+  esac
+  done
+  IFS=$_G_save_IFS
+  require_check_ifs_backslash=:
+}
+
 
 ## ----------------- ##
 ## Global variables. ##
@@ -580,16 +623,16 @@
   {
     $debug_cmd
 
-    func_quote_for_eval "$2"
-    eval "$1+=\\ \$func_quote_for_eval_result"
+    func_quote_arg pretty "$2"
+    eval "$1+=\\ \$func_quote_arg_result"
   }'
 else
   func_append_quoted ()
   {
     $debug_cmd
 
-    func_quote_for_eval "$2"
-    eval "$1=\$$1\\ \$func_quote_for_eval_result"
+    func_quote_arg pretty "$2"
+    eval "$1=\$$1\\ \$func_quote_arg_result"
   }
 fi
 
@@ -1091,85 +1134,203 @@
 }
 
 
-# func_quote_for_eval ARG...
-# --------------------------
-# Aesthetically quote ARGs to be evaled later.
-# This function returns two values:
-#   i) func_quote_for_eval_result
-#      double-quoted, suitable for a subsequent eval
-#  ii) func_quote_for_eval_unquoted_result
-#      has all characters that are still active within double
-#      quotes backslashified.
-func_quote_for_eval ()
+# func_quote_portable EVAL ARG
+# ----------------------------
+# Internal function to portably implement func_quote_arg.  Note that we still
+# keep attention to performance here so we as much as possible try to avoid
+# calling sed binary (so far O(N) complexity as long as func_append is O(1)).
+func_quote_portable ()
 {
     $debug_cmd
 
-    func_quote_for_eval_unquoted_result=
-    func_quote_for_eval_result=
-    while test 0 -lt $#; do
-      case $1 in
+    $require_check_ifs_backslash
+
+    func_quote_portable_result=$2
+
+    # one-time-loop (easy break)
+    while true
+    do
+      if $1; then
+        func_quote_portable_result=`$ECHO "$2" | $SED \
+          -e "$sed_double_quote_subst" -e "$sed_double_backslash"`
+        break
+      fi
+
+      # Quote for eval.
+      case $func_quote_portable_result in
         *[\\\`\"\$]*)
-	  _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
-        *)
-          _G_unquoted_arg=$1 ;;
-      esac
-      if test -n "$func_quote_for_eval_unquoted_result"; then
-	func_append func_quote_for_eval_unquoted_result " $_G_unquoted_arg"
-      else
-        func_append func_quote_for_eval_unquoted_result "$_G_unquoted_arg"
-      fi
+          # Fallback to sed for $func_check_bs_ifs_broken=:, or when the string
+          # contains the shell wildcard characters.
+          case $check_ifs_backshlash_broken$func_quote_portable_result in
+            :*|*[\[\*\?]*)
+              func_quote_portable_result=`$ECHO "$func_quote_portable_result" \
+                  | $SED "$sed_quote_subst"`
+              break
+              ;;
+          esac
 
-      case $_G_unquoted_arg in
-        # Double-quote args containing shell metacharacters to delay
-        # word splitting, command substitution and variable expansion
-        # for a subsequent eval.
-        # Many Bourne shells cannot handle close brackets correctly
-        # in scan sets, so we specify it separately.
-        *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
-          _G_quoted_arg=\"$_G_unquoted_arg\"
+          func_quote_portable_old_IFS=$IFS
+          for _G_char in '\' '`' '"' '$'
+          do
+            # STATE($1) PREV($2) SEPARATOR($3)
+            set start "" ""
+            func_quote_portable_result=dummy"$_G_char$func_quote_portable_result$_G_char"dummy
+            IFS=$_G_char
+            for _G_part in $func_quote_portable_result
+            do
+              case $1 in
+              quote)
+                func_append func_quote_portable_result "$3$2"
+                set quote "$_G_part" "\\$_G_char"
+                ;;
+              start)
+                set first "" ""
+                func_quote_portable_result=
+                ;;
+              first)
+                set quote "$_G_part" ""
+                ;;
+              esac
+            done
+          done
+          IFS=$func_quote_portable_old_IFS
           ;;
-        *)
-          _G_quoted_arg=$_G_unquoted_arg
-	  ;;
+        *) ;;
       esac
-
-      if test -n "$func_quote_for_eval_result"; then
-	func_append func_quote_for_eval_result " $_G_quoted_arg"
-      else
-        func_append func_quote_for_eval_result "$_G_quoted_arg"
-      fi
-      shift
+      break
     done
+
+    func_quote_portable_unquoted_result=$func_quote_portable_result
+    case $func_quote_portable_result in
+      # double-quote args containing shell metacharacters to delay
+      # word splitting, command substitution and variable expansion
+      # for a subsequent eval.
+      # many bourne shells cannot handle close brackets correctly
+      # in scan sets, so we specify it separately.
+      *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
+        func_quote_portable_result=\"$func_quote_portable_result\"
+        ;;
+    esac
 }
 
 
-# func_quote_for_expand ARG
-# -------------------------
-# Aesthetically quote ARG to be evaled later; same as above,
-# but do not quote variable references.
-func_quote_for_expand ()
+# func_quotefast_eval ARG
+# -----------------------
+# Quote one ARG (internal).  This is equivalent to 'func_quote_arg eval ARG',
+# but optimized for speed.  Result is stored in $func_quotefast_eval.
+if test xyes = `(x=; printf -v x %q yes; echo x"$x") 2>/dev/null`; then
+  printf -v _GL_test_printf_tilde %q '~'
+  if test '\~' = "$_GL_test_printf_tilde"; then
+    func_quotefast_eval ()
+    {
+      printf -v func_quotefast_eval_result %q "$1"
+    }
+  else
+    # Broken older Bash implementations.  Make those faster too if possible.
+    func_quotefast_eval ()
+    {
+      case $1 in
+        '~'*)
+          func_quote_portable false "$1"
+          func_quotefast_eval_result=$func_quote_portable_result
+          ;;
+        *)
+          printf -v func_quotefast_eval_result %q "$1"
+          ;;
+      esac
+    }
+  fi
+else
+  func_quotefast_eval ()
+  {
+    func_quote_portable false "$1"
+    func_quotefast_eval_result=$func_quote_portable_result
+  }
+fi
+
+
+# func_quote_arg MODEs ARG
+# ------------------------
+# Quote one ARG to be evaled later.  MODEs argument may contain zero or more
+# specifiers listed below separated by ',' character.  This function returns two
+# values:
+#   i) func_quote_arg_result
+#      double-quoted (when needed), suitable for a subsequent eval
+#  ii) func_quote_arg_unquoted_result
+#      has all characters that are still active within double
+#      quotes backslashified.  Available only if 'unquoted' is specified.
+#
+# Available modes:
+# ----------------
+# 'eval' (default)
+#       - escape shell special characters
+# 'expand'
+#       - the same as 'eval';  but do not quote variable references
+# 'pretty'
+#       - request aesthetic output, i.e. '"a b"' instead of 'a\ b'.  This might
+#         be used later in func_quote to get output like: 'echo "a b"' instead
+#         of 'echo a\ b'.  This is slower than default on some shells.
+# 'unquoted'
+#       - produce also $func_quote_arg_unquoted_result which does not contain
+#         wrapping double-quotes.
+#
+# Examples for 'func_quote_arg pretty,unquoted string':
+#
+#   string      | *_result              | *_unquoted_result
+#   ------------+-----------------------+-------------------
+#   "           | \"                    | \"
+#   a b         | "a b"                 | a b
+#   "a b"       | "\"a b\""             | \"a b\"
+#   *           | "*"                   | *
+#   z="${x-$y}" | "z=\"\${x-\$y}\""     | z=\"\${x-\$y}\"
+#
+# Examples for 'func_quote_arg pretty,unquoted,expand string':
+#
+#   string        |   *_result          |  *_unquoted_result
+#   --------------+---------------------+--------------------
+#   z="${x-$y}"   | "z=\"${x-$y}\""     | z=\"${x-$y}\"
+func_quote_arg ()
 {
-    $debug_cmd
-
-    case $1 in
-      *[\\\`\"]*)
-	_G_arg=`$ECHO "$1" | $SED \
-	    -e "$sed_double_quote_subst" -e "$sed_double_backslash"` ;;
-      *)
-        _G_arg=$1 ;;
-    esac
-
-    case $_G_arg in
-      # Double-quote args containing shell metacharacters to delay
-      # word splitting and command substitution for a subsequent eval.
-      # Many Bourne shells cannot handle close brackets correctly
-      # in scan sets, so we specify it separately.
-      *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
-        _G_arg=\"$_G_arg\"
+    _G_quote_expand=false
+    case ,$1, in
+      *,expand,*)
+        _G_quote_expand=:
         ;;
     esac
 
-    func_quote_for_expand_result=$_G_arg
+    case ,$1, in
+      *,pretty,*|*,expand,*|*,unquoted,*)
+        func_quote_portable $_G_quote_expand "$2"
+        func_quote_arg_result=$func_quote_portable_result
+        func_quote_arg_unquoted_result=$func_quote_portable_unquoted_result
+        ;;
+      *)
+        # Faster quote-for-eval for some shells.
+        func_quotefast_eval "$2"
+        func_quote_arg_result=$func_quotefast_eval_result
+        ;;
+    esac
+}
+
+
+# func_quote MODEs ARGs...
+# ------------------------
+# Quote all ARGs to be evaled later and join them into single command.  See
+# func_quote_arg's description for more info.
+func_quote ()
+{
+    $debug_cmd
+    _G_func_quote_mode=$1 ; shift
+    func_quote_result=
+    while test 0 -lt $#; do
+      func_quote_arg "$_G_func_quote_mode" "$1"
+      if test -n "$func_quote_result"; then
+        func_append func_quote_result " $func_quote_arg_result"
+      else
+        func_append func_quote_result "$func_quote_arg_result"
+      fi
+      shift
+    done
 }
 
 
@@ -1215,8 +1376,8 @@
     _G_cmd=$1
     _G_fail_exp=${2-':'}
 
-    func_quote_for_expand "$_G_cmd"
-    eval "func_notquiet $func_quote_for_expand_result"
+    func_quote_arg pretty,expand "$_G_cmd"
+    eval "func_notquiet $func_quote_arg_result"
 
     $opt_dry_run || {
       eval "$_G_cmd"
@@ -1241,8 +1402,8 @@
     _G_fail_exp=${2-':'}
 
     $opt_quiet || {
-      func_quote_for_expand "$_G_cmd"
-      eval "func_echo $func_quote_for_expand_result"
+      func_quote_arg expand,pretty "$_G_cmd"
+      eval "func_echo $func_quote_arg_result"
     }
 
     $opt_dry_run || {
@@ -1369,30 +1530,26 @@
 # End:
 #! /bin/sh
 
-# Set a version string for this script.
-scriptversion=2014-01-07.03; # UTC
-
 # A portable, pluggable option parser for Bourne shell.
 # Written by Gary V. Vaughan, 2010
 
-# Copyright (C) 2010-2015 Free Software Foundation, Inc.
-# This is free software; see the source for copying conditions.  There is NO
-# warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# This is free software.  There is NO warranty; not even for
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Copyright (C) 2010-2019, 2021 Bootstrap Authors
+#
+# This file is dual licensed under the terms of the MIT license
+# <https://opensource.org/license/MIT>, and GPL version 2 or later
+# <http://www.gnu.org/licenses/gpl-2.0.html>.  You must apply one of
+# these licenses when using or redistributing this software or any of
+# the files within it.  See the URLs above, or the file `LICENSE`
+# included in the Bootstrap distribution for the full license texts.
 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
+# Please report bugs or propose patches to:
+# <https://github.com/gnulib-modules/bootstrap/issues>
 
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-# Please report bugs or propose patches to gary@gnu.org.
+# Set a version string for this script.
+scriptversion=2019-02-19.15; # UTC
 
 
 ## ------ ##
@@ -1415,7 +1572,7 @@
 #
 # In order for the '--version' option to work, you will need to have a
 # suitably formatted comment like the one at the top of this file
-# starting with '# Written by ' and ending with '# warranty; '.
+# starting with '# Written by ' and ending with '# Copyright'.
 #
 # For '-h' and '--help' to work, you will also need a one line
 # description of your script's purpose in a comment directly above the
@@ -1427,7 +1584,7 @@
 # to display verbose messages only when your user has specified
 # '--verbose'.
 #
-# After sourcing this file, you can plug processing for additional
+# After sourcing this file, you can plug in processing for additional
 # options by amending the variables from the 'Configuration' section
 # below, and following the instructions in the 'Option parsing'
 # section further down.
@@ -1476,8 +1633,8 @@
 ## ------------------------- ##
 
 # This section contains functions for adding, removing, and running hooks
-# to the main code.  A hook is just a named list of of function, that can
-# be run in order later on.
+# in the main code.  A hook is just a list of function names that can be
+# run in order later on.
 
 # func_hookable FUNC_NAME
 # -----------------------
@@ -1510,7 +1667,8 @@
 
 # func_remove_hook FUNC_NAME HOOK_FUNC
 # ------------------------------------
-# Remove HOOK_FUNC from the list of functions called by FUNC_NAME.
+# Remove HOOK_FUNC from the list of hook functions to be called by
+# FUNC_NAME.
 func_remove_hook ()
 {
     $debug_cmd
@@ -1519,10 +1677,28 @@
 }
 
 
+# func_propagate_result FUNC_NAME_A FUNC_NAME_B
+# ---------------------------------------------
+# If the *_result variable of FUNC_NAME_A _is set_, assign its value to
+# *_result variable of FUNC_NAME_B.
+func_propagate_result ()
+{
+    $debug_cmd
+
+    func_propagate_result_result=:
+    if eval "test \"\${${1}_result+set}\" = set"
+    then
+      eval "${2}_result=\$${1}_result"
+    else
+      func_propagate_result_result=false
+    fi
+}
+
+
 # func_run_hooks FUNC_NAME [ARG]...
 # ---------------------------------
 # Run all hook functions registered to FUNC_NAME.
-# It is assumed that the list of hook functions contains nothing more
+# It's assumed that the list of hook functions contains nothing more
 # than a whitespace-delimited list of legal shell function names, and
 # no effort is wasted trying to catch shell meta-characters or preserve
 # whitespace.
@@ -1532,22 +1708,19 @@
 
     case " $hookable_fns " in
       *" $1 "*) ;;
-      *) func_fatal_error "'$1' does not support hook funcions.n" ;;
+      *) func_fatal_error "'$1' does not support hook functions." ;;
     esac
 
     eval _G_hook_fns=\$$1_hooks; shift
 
     for _G_hook in $_G_hook_fns; do
-      eval $_G_hook '"$@"'
-
-      # store returned options list back into positional
-      # parameters for next 'cmd' execution.
-      eval _G_hook_result=\$${_G_hook}_result
-      eval set dummy "$_G_hook_result"; shift
+      func_unset "${_G_hook}_result"
+      eval $_G_hook '${1+"$@"}'
+      func_propagate_result $_G_hook func_run_hooks
+      if $func_propagate_result_result; then
+        eval set dummy "$func_run_hooks_result"; shift
+      fi
     done
-
-    func_quote_for_eval ${1+"$@"}
-    func_run_hooks_result=$func_quote_for_eval_result
 }
 
 
@@ -1557,10 +1730,18 @@
 ## --------------- ##
 
 # In order to add your own option parsing hooks, you must accept the
-# full positional parameter list in your hook function, remove any
-# options that you action, and then pass back the remaining unprocessed
-# options in '<hooked_function_name>_result', escaped suitably for
-# 'eval'.  Like this:
+# full positional parameter list from your hook function.  You may remove
+# or edit any options that you action, and then pass back the remaining
+# unprocessed options in '<hooked_function_name>_result', escaped
+# suitably for 'eval'.
+#
+# The '<hooked_function_name>_result' variable is automatically unset
+# before your hook gets called; for best performance, only set the
+# *_result variable when necessary (i.e. don't call the 'func_quote'
+# function unnecessarily because it can be an expensive operation on some
+# machines).
+#
+# Like this:
 #
 #    my_options_prep ()
 #    {
@@ -1570,9 +1751,8 @@
 #        usage_message=$usage_message'
 #      -s, --silent       don'\''t print informational messages
 #    '
-#
-#        func_quote_for_eval ${1+"$@"}
-#        my_options_prep_result=$func_quote_for_eval_result
+#        # No change in '$@' (ignored completely by this hook).  Leave
+#        # my_options_prep_result variable intact.
 #    }
 #    func_add_hook func_options_prep my_options_prep
 #
@@ -1581,25 +1761,36 @@
 #    {
 #        $debug_cmd
 #
-#        # Note that for efficiency, we parse as many options as we can
+#        args_changed=false
+#
+#        # Note that, for efficiency, we parse as many options as we can
 #        # recognise in a loop before passing the remainder back to the
 #        # caller on the first unrecognised argument we encounter.
 #        while test $# -gt 0; do
 #          opt=$1; shift
 #          case $opt in
-#            --silent|-s) opt_silent=: ;;
+#            --silent|-s) opt_silent=:
+#                         args_changed=:
+#                         ;;
 #            # Separate non-argument short options:
 #            -s*)         func_split_short_opt "$_G_opt"
 #                         set dummy "$func_split_short_opt_name" \
 #                             "-$func_split_short_opt_arg" ${1+"$@"}
 #                         shift
+#                         args_changed=:
 #                         ;;
-#            *)            set dummy "$_G_opt" "$*"; shift; break ;;
+#            *)           # Make sure the first unrecognised option "$_G_opt"
+#                         # is added back to "$@" in case we need it later,
+#                         # if $args_changed was set to 'true'.
+#                         set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
 #          esac
 #        done
 #
-#        func_quote_for_eval ${1+"$@"}
-#        my_silent_option_result=$func_quote_for_eval_result
+#        # Only call 'func_quote' here if we processed at least one argument.
+#        if $args_changed; then
+#          func_quote eval ${1+"$@"}
+#          my_silent_option_result=$func_quote_result
+#        fi
 #    }
 #    func_add_hook func_parse_options my_silent_option
 #
@@ -1610,17 +1801,26 @@
 #
 #        $opt_silent && $opt_verbose && func_fatal_help "\
 #    '--silent' and '--verbose' options are mutually exclusive."
-#
-#        func_quote_for_eval ${1+"$@"}
-#        my_option_validation_result=$func_quote_for_eval_result
 #    }
 #    func_add_hook func_validate_options my_option_validation
 #
-# You'll alse need to manually amend $usage_message to reflect the extra
+# You'll also need to manually amend $usage_message to reflect the extra
 # options you parse.  It's preferable to append if you can, so that
 # multiple option parsing hooks can be added safely.
 
 
+# func_options_finish [ARG]...
+# ----------------------------
+# Finishing the option parse loop (call 'func_options' hooks ATM).
+func_options_finish ()
+{
+    $debug_cmd
+
+    func_run_hooks func_options ${1+"$@"}
+    func_propagate_result func_run_hooks func_options_finish
+}
+
+
 # func_options [ARG]...
 # ---------------------
 # All the functions called inside func_options are hookable. See the
@@ -1630,17 +1830,27 @@
 {
     $debug_cmd
 
-    func_options_prep ${1+"$@"}
-    eval func_parse_options \
-        ${func_options_prep_result+"$func_options_prep_result"}
-    eval func_validate_options \
-        ${func_parse_options_result+"$func_parse_options_result"}
+    _G_options_quoted=false
 
-    eval func_run_hooks func_options \
-        ${func_validate_options_result+"$func_validate_options_result"}
+    for my_func in options_prep parse_options validate_options options_finish
+    do
+      func_unset func_${my_func}_result
+      func_unset func_run_hooks_result
+      eval func_$my_func '${1+"$@"}'
+      func_propagate_result func_$my_func func_options
+      if $func_propagate_result_result; then
+        eval set dummy "$func_options_result"; shift
+        _G_options_quoted=:
+      fi
+    done
 
-    # save modified positional parameters for caller
-    func_options_result=$func_run_hooks_result
+    $_G_options_quoted || {
+      # As we (func_options) are top-level options-parser function and
+      # nobody quoted "$@" for us yet, we need to do it explicitly for
+      # caller.
+      func_quote eval ${1+"$@"}
+      func_options_result=$func_quote_result
+    }
 }
 
 
@@ -1649,9 +1859,8 @@
 # All initialisations required before starting the option parse loop.
 # Note that when calling hook functions, we pass through the list of
 # positional parameters.  If a hook function modifies that list, and
-# needs to propogate that back to rest of this script, then the complete
-# modified list must be put in 'func_run_hooks_result' before
-# returning.
+# needs to propagate that back to rest of this script, then the complete
+# modified list must be put in 'func_run_hooks_result' before returning.
 func_hookable func_options_prep
 func_options_prep ()
 {
@@ -1662,9 +1871,7 @@
     opt_warning_types=
 
     func_run_hooks func_options_prep ${1+"$@"}
-
-    # save modified positional parameters for caller
-    func_options_prep_result=$func_run_hooks_result
+    func_propagate_result func_run_hooks func_options_prep
 }
 
 
@@ -1676,25 +1883,32 @@
 {
     $debug_cmd
 
-    func_parse_options_result=
-
+    _G_parse_options_requote=false
     # this just eases exit handling
     while test $# -gt 0; do
       # Defer to hook functions for initial option parsing, so they
       # get priority in the event of reusing an option name.
       func_run_hooks func_parse_options ${1+"$@"}
-
-      # Adjust func_parse_options positional parameters to match
-      eval set dummy "$func_run_hooks_result"; shift
+      func_propagate_result func_run_hooks func_parse_options
+      if $func_propagate_result_result; then
+        eval set dummy "$func_parse_options_result"; shift
+        # Even though we may have changed "$@", we passed the "$@" array
+        # down into the hook and it quoted it for us (because we are in
+        # this if-branch).  No need to quote it again.
+        _G_parse_options_requote=false
+      fi
 
       # Break out of the loop if we already parsed every option.
       test $# -gt 0 || break
 
+      # We expect that one of the options parsed in this function matches
+      # and thus we remove _G_opt from "$@" and need to re-quote.
+      _G_match_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
         --debug|-x)   debug_cmd='set -x'
-                      func_echo "enabling shell trace mode"
+                      func_echo "enabling shell trace mode" >&2
                       $debug_cmd
                       ;;
 
@@ -1704,7 +1918,10 @@
 		      ;;
 
         --warnings|--warning|-W)
-                      test $# = 0 && func_missing_arg $_G_opt && break
+                      if test $# = 0 && func_missing_arg $_G_opt; then
+                        _G_parse_options_requote=:
+                        break
+                      fi
                       case " $warning_categories $1" in
                         *" $1 "*)
                           # trailing space prevents matching last $1 above
@@ -1757,15 +1974,24 @@
                       shift
                       ;;
 
-        --)           break ;;
+        --)           _G_parse_options_requote=: ; break ;;
         -*)           func_fatal_help "unrecognised option: '$_G_opt'" ;;
-        *)            set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
+        *)            set dummy "$_G_opt" ${1+"$@"}; shift
+                      _G_match_parse_options=false
+                      break
+                      ;;
       esac
+
+      if $_G_match_parse_options; then
+        _G_parse_options_requote=:
+      fi
     done
 
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    func_parse_options_result=$func_quote_for_eval_result
+    if $_G_parse_options_requote; then
+      # save modified positional parameters for caller
+      func_quote eval ${1+"$@"}
+      func_parse_options_result=$func_quote_result
+    fi
 }
 
 
@@ -1782,12 +2008,10 @@
     test -n "$opt_warning_types" || opt_warning_types=" $warning_categories"
 
     func_run_hooks func_validate_options ${1+"$@"}
+    func_propagate_result func_run_hooks func_validate_options
 
     # Bail if the options were screwed!
     $exit_cmd $EXIT_FAILURE
-
-    # save modified positional parameters for caller
-    func_validate_options_result=$func_run_hooks_result
 }
 
 
@@ -1843,8 +2067,8 @@
 
 # func_split_equals STRING
 # ------------------------
-# Set func_split_equals_lhs and func_split_equals_rhs shell variables after
-# splitting STRING at the '=' sign.
+# Set func_split_equals_lhs and func_split_equals_rhs shell variables
+# after splitting STRING at the '=' sign.
 test -z "$_G_HAVE_XSI_OPS" \
     && (eval 'x=a/b/c;
       test 5aa/bb/cc = "${#x}${x%%/*}${x%/*}${x#*/}${x##*/}"') 2>/dev/null \
@@ -1859,8 +2083,9 @@
 
       func_split_equals_lhs=${1%%=*}
       func_split_equals_rhs=${1#*=}
-      test "x$func_split_equals_lhs" = "x$1" \
-        && func_split_equals_rhs=
+      if test "x$func_split_equals_lhs" = "x$1"; then
+        func_split_equals_rhs=
+      fi
   }'
 else
   # ...otherwise fall back to using expr, which is often a shell builtin.
@@ -1870,7 +2095,7 @@
 
       func_split_equals_lhs=`expr "x$1" : 'x\([^=]*\)'`
       func_split_equals_rhs=
-      test "x$func_split_equals_lhs" = "x$1" \
+      test "x$func_split_equals_lhs=" = "x$1" \
         || func_split_equals_rhs=`expr "x$1" : 'x[^=]*=\(.*\)$'`
   }
 fi #func_split_equals
@@ -1896,7 +2121,7 @@
   {
       $debug_cmd
 
-      func_split_short_opt_name=`expr "x$1" : 'x-\(.\)'`
+      func_split_short_opt_name=`expr "x$1" : 'x\(-.\)'`
       func_split_short_opt_arg=`expr "x$1" : 'x-.\(.*\)$'`
   }
 fi #func_split_short_opt
@@ -1938,31 +2163,44 @@
 # func_version
 # ------------
 # Echo version message to standard output and exit.
+# The version message is extracted from the calling file's header
+# comments, with leading '# ' stripped:
+#   1. First display the progname and version
+#   2. Followed by the header comment line matching  /^# Written by /
+#   3. Then a blank line followed by the first following line matching
+#      /^# Copyright /
+#   4. Immediately followed by any lines between the previous matches,
+#      except lines preceding the intervening completely blank line.
+# For example, see the header comments of this file.
 func_version ()
 {
     $debug_cmd
 
     printf '%s\n' "$progname $scriptversion"
     $SED -n '
-        /(C)/!b go
-        :more
-        /\./!{
-          N
-          s|\n# | |
-          b more
+        /^# Written by /!b
+        s|^# ||; p; n
+
+        :fwd2blnk
+        /./ {
+          n
+          b fwd2blnk
         }
-        :go
-        /^# Written by /,/# warranty; / {
-          s|^# ||
-          s|^# *$||
-          s|\((C)\)[ 0-9,-]*[ ,-]\([1-9][0-9]* \)|\1 \2|
-          p
+        p; n
+
+        :holdwrnt
+        s|^# ||
+        s|^# *$||
+        /^Copyright /!{
+          /./H
+          n
+          b holdwrnt
         }
-        /^# Written by / {
-          s|^# ||
-          p
-        }
-        /^warranty; /q' < "$progpath"
+
+        s|\((C)\)[ 0-9,-]*[ ,-]\([1-9][0-9]* \)|\1 \2|
+        G
+        s|\(\n\)\n*|\1|g
+        p; q' < "$progpath"
 
     exit $?
 }
@@ -1972,12 +2210,12 @@
 # mode: shell-script
 # sh-indentation: 2
 # eval: (add-hook 'before-save-hook 'time-stamp)
-# time-stamp-pattern: "10/scriptversion=%:y-%02m-%02d.%02H; # UTC"
+# time-stamp-pattern: "30/scriptversion=%:y-%02m-%02d.%02H; # UTC"
 # time-stamp-time-zone: "UTC"
 # End:
 
 # Set a version string.
-scriptversion='(GNU libtool) 2.4.6'
+scriptversion='(GNU libtool) 2.4.7'
 
 
 # func_echo ARG...
@@ -2068,7 +2306,7 @@
        compiler:       $LTCC
        compiler flags: $LTCFLAGS
        linker:         $LD (gnu? $with_gnu_ld)
-       version:        $progname (GNU libtool) 2.4.6
+       version:        $progname (GNU libtool) 2.4.7
        automake:       `($AUTOMAKE --version) 2>/dev/null |$SED 1q`
        autoconf:       `($AUTOCONF --version) 2>/dev/null |$SED 1q`
 
@@ -2124,7 +2362,7 @@
 # a configuration failure hint, and exit.
 func_fatal_configuration ()
 {
-    func__fatal_error ${1+"$@"} \
+    func_fatal_error ${1+"$@"} \
       "See the $PACKAGE documentation for more information." \
       "Fatal configuration error."
 }
@@ -2270,6 +2508,8 @@
     nonopt=
     preserve_args=
 
+    _G_rc_lt_options_prep=:
+
     # Shorthand for --mode=foo, only valid as the first argument
     case $1 in
     clean|clea|cle|cl)
@@ -2293,11 +2533,16 @@
     uninstall|uninstal|uninsta|uninst|unins|unin|uni|un|u)
       shift; set dummy --mode uninstall ${1+"$@"}; shift
       ;;
+    *)
+      _G_rc_lt_options_prep=false
+      ;;
     esac
 
-    # Pass back the list of options.
-    func_quote_for_eval ${1+"$@"}
-    libtool_options_prep_result=$func_quote_for_eval_result
+    if $_G_rc_lt_options_prep; then
+      # Pass back the list of options.
+      func_quote eval ${1+"$@"}
+      libtool_options_prep_result=$func_quote_result
+    fi
 }
 func_add_hook func_options_prep libtool_options_prep
 
@@ -2309,9 +2554,12 @@
 {
     $debug_cmd
 
+    _G_rc_lt_parse_options=false
+
     # Perform our own loop to consume as many options as possible in
     # each iteration.
     while test $# -gt 0; do
+      _G_match_lt_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
@@ -2386,15 +2634,20 @@
                         func_append preserve_args " $_G_opt"
                         ;;
 
-	# An option not handled by this hook function:
-        *)		set dummy "$_G_opt" ${1+"$@"};	shift; break  ;;
+        # An option not handled by this hook function:
+        *)              set dummy "$_G_opt" ${1+"$@"} ; shift
+                        _G_match_lt_parse_options=false
+                        break
+                        ;;
       esac
+      $_G_match_lt_parse_options && _G_rc_lt_parse_options=:
     done
 
-
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    libtool_parse_options_result=$func_quote_for_eval_result
+    if $_G_rc_lt_parse_options; then
+      # save modified positional parameters for caller
+      func_quote eval ${1+"$@"}
+      libtool_parse_options_result=$func_quote_result
+    fi
 }
 func_add_hook func_parse_options libtool_parse_options
 
@@ -2451,8 +2704,8 @@
     }
 
     # Pass back the unparsed argument list
-    func_quote_for_eval ${1+"$@"}
-    libtool_validate_options_result=$func_quote_for_eval_result
+    func_quote eval ${1+"$@"}
+    libtool_validate_options_result=$func_quote_result
 }
 func_add_hook func_validate_options libtool_validate_options
 
@@ -3418,8 +3671,8 @@
       esac
     done
 
-    func_quote_for_eval "$libobj"
-    test "X$libobj" != "X$func_quote_for_eval_result" \
+    func_quote_arg pretty "$libobj"
+    test "X$libobj" != "X$func_quote_arg_result" \
       && $ECHO "X$libobj" | $GREP '[]~#^*{};<>?"'"'"'	 &()|`$[]' \
       && func_warning "libobj name '$libobj' may not contain shell special characters."
     func_dirname_and_basename "$obj" "/" ""
@@ -3492,8 +3745,8 @@
 
     func_to_tool_file "$srcfile" func_convert_file_msys_to_w32
     srcfile=$func_to_tool_file_result
-    func_quote_for_eval "$srcfile"
-    qsrcfile=$func_quote_for_eval_result
+    func_quote_arg pretty "$srcfile"
+    qsrcfile=$func_quote_arg_result
 
     # Only build a PIC object if we are building libtool libraries.
     if test yes = "$build_libtool_libs"; then
@@ -3648,7 +3901,8 @@
   -prefer-non-pic   try to build non-PIC objects only
   -shared           do not build a '.o' file suitable for static linking
   -static           only build a '.o' file suitable for static linking
-  -Wc,FLAG          pass FLAG directly to the compiler
+  -Wc,FLAG
+  -Xcompiler FLAG   pass FLAG directly to the compiler
 
 COMPILE-COMMAND is a command to be used in creating a 'standard' object file
 from the given SOURCEFILE.
@@ -3754,6 +4008,8 @@
   -weak LIBNAME     declare that the target provides the LIBNAME interface
   -Wc,FLAG
   -Xcompiler FLAG   pass linker-specific FLAG directly to the compiler
+  -Wa,FLAG
+  -Xassembler FLAG  pass linker-specific FLAG directly to the assembler
   -Wl,FLAG
   -Xlinker FLAG     pass linker-specific FLAG directly to the linker
   -XCClinker FLAG   pass link-specific FLAG to the compiler driver (CC)
@@ -4096,8 +4352,8 @@
        case $nonopt in *shtool*) :;; *) false;; esac
     then
       # Aesthetically quote it.
-      func_quote_for_eval "$nonopt"
-      install_prog="$func_quote_for_eval_result "
+      func_quote_arg pretty "$nonopt"
+      install_prog="$func_quote_arg_result "
       arg=$1
       shift
     else
@@ -4107,8 +4363,8 @@
 
     # The real first argument should be the name of the installation program.
     # Aesthetically quote it.
-    func_quote_for_eval "$arg"
-    func_append install_prog "$func_quote_for_eval_result"
+    func_quote_arg pretty "$arg"
+    func_append install_prog "$func_quote_arg_result"
     install_shared_prog=$install_prog
     case " $install_prog " in
       *[\\\ /]cp\ *) install_cp=: ;;
@@ -4165,12 +4421,12 @@
       esac
 
       # Aesthetically quote the argument.
-      func_quote_for_eval "$arg"
-      func_append install_prog " $func_quote_for_eval_result"
+      func_quote_arg pretty "$arg"
+      func_append install_prog " $func_quote_arg_result"
       if test -n "$arg2"; then
-	func_quote_for_eval "$arg2"
+	func_quote_arg pretty "$arg2"
       fi
-      func_append install_shared_prog " $func_quote_for_eval_result"
+      func_append install_shared_prog " $func_quote_arg_result"
     done
 
     test -z "$install_prog" && \
@@ -4181,8 +4437,8 @@
 
     if test -n "$install_override_mode" && $no_mode; then
       if $install_cp; then :; else
-	func_quote_for_eval "$install_override_mode"
-	func_append install_shared_prog " -m $func_quote_for_eval_result"
+	func_quote_arg pretty "$install_override_mode"
+	func_append install_shared_prog " -m $func_quote_arg_result"
       fi
     fi
 
@@ -4478,8 +4734,8 @@
 	        relink_command=`$ECHO "$relink_command" | $SED 's%@OUTPUT@%'"$outputname"'%g'`
 
 	        $opt_quiet || {
-	          func_quote_for_expand "$relink_command"
-		  eval "func_echo $func_quote_for_expand_result"
+	          func_quote_arg expand,pretty "$relink_command"
+		  eval "func_echo $func_quote_arg_result"
 	        }
 	        if eval "$relink_command"; then :
 	          else
@@ -5258,7 +5514,8 @@
   if test \"\$libtool_execute_magic\" != \"$magic\"; then
     file=\"\$0\""
 
-    qECHO=`$ECHO "$ECHO" | $SED "$sed_quote_subst"`
+    func_quote_arg pretty "$ECHO"
+    qECHO=$func_quote_arg_result
     $ECHO "\
 
 # A function that is used when there is no print builtin or printf.
@@ -5268,7 +5525,7 @@
 \$1
 _LTECHO_EOF'
 }
-    ECHO=\"$qECHO\"
+    ECHO=$qECHO
   fi
 
 # Very basic option parsing. These options are (a) specific to
@@ -6611,9 +6868,9 @@
     while test "$#" -gt 0; do
       arg=$1
       shift
-      func_quote_for_eval "$arg"
-      qarg=$func_quote_for_eval_unquoted_result
-      func_append libtool_args " $func_quote_for_eval_result"
+      func_quote_arg pretty,unquoted "$arg"
+      qarg=$func_quote_arg_unquoted_result
+      func_append libtool_args " $func_quote_arg_result"
 
       # If the previous option needs an argument, assign it.
       if test -n "$prev"; then
@@ -6849,6 +7106,13 @@
 	  prev=
 	  continue
 	  ;;
+	xassembler)
+	  func_append compiler_flags " -Xassembler $qarg"
+	  prev=
+	  func_append compile_command " -Xassembler $qarg"
+	  func_append finalize_command " -Xassembler $qarg"
+	  continue
+	  ;;
 	xcclinker)
 	  func_append linker_flags " $qarg"
 	  func_append compiler_flags " $qarg"
@@ -7019,7 +7283,7 @@
 	    # These systems don't actually have a C library (as such)
 	    test X-lc = "X$arg" && continue
 	    ;;
-	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig*)
+	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig* | *-*-midnightbsd*)
 	    # Do not include libc due to us having libc/libc_r.
 	    test X-lc = "X$arg" && continue
 	    ;;
@@ -7039,7 +7303,7 @@
 	  esac
 	elif test X-lc_r = "X$arg"; then
 	 case $host in
-	 *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig*)
+	 *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig* | *-*-midnightbsd*)
 	   # Do not include libc_r directly, use -pthread flag.
 	   continue
 	   ;;
@@ -7069,8 +7333,20 @@
 	prev=xcompiler
 	continue
 	;;
-
-      -mt|-mthreads|-kthread|-Kthread|-pthread|-pthreads|--thread-safe \
+     # Solaris ld rejects as of 11.4. Refer to Oracle bug 22985199.
+     -pthread)
+	case $host in
+	  *solaris2*) ;;
+	  *)
+	    case "$new_inherited_linker_flags " in
+	        *" $arg "*) ;;
+	        * ) func_append new_inherited_linker_flags " $arg" ;;
+	    esac
+	  ;;
+	esac
+	continue
+	;;
+      -mt|-mthreads|-kthread|-Kthread|-pthreads|--thread-safe \
       |-threads|-fopenmp|-openmp|-mp|-xopenmp|-omp|-qsmp=*)
 	func_append compiler_flags " $arg"
 	func_append compile_command " $arg"
@@ -7211,9 +7487,9 @@
 	save_ifs=$IFS; IFS=,
 	for flag in $args; do
 	  IFS=$save_ifs
-          func_quote_for_eval "$flag"
-	  func_append arg " $func_quote_for_eval_result"
-	  func_append compiler_flags " $func_quote_for_eval_result"
+          func_quote_arg pretty "$flag"
+	  func_append arg " $func_quote_arg_result"
+	  func_append compiler_flags " $func_quote_arg_result"
 	done
 	IFS=$save_ifs
 	func_stripname ' ' '' "$arg"
@@ -7227,16 +7503,21 @@
 	save_ifs=$IFS; IFS=,
 	for flag in $args; do
 	  IFS=$save_ifs
-          func_quote_for_eval "$flag"
-	  func_append arg " $wl$func_quote_for_eval_result"
-	  func_append compiler_flags " $wl$func_quote_for_eval_result"
-	  func_append linker_flags " $func_quote_for_eval_result"
+          func_quote_arg pretty "$flag"
+	  func_append arg " $wl$func_quote_arg_result"
+	  func_append compiler_flags " $wl$func_quote_arg_result"
+	  func_append linker_flags " $func_quote_arg_result"
 	done
 	IFS=$save_ifs
 	func_stripname ' ' '' "$arg"
 	arg=$func_stripname_result
 	;;
 
+      -Xassembler)
+        prev=xassembler
+        continue
+        ;;
+
       -Xcompiler)
 	prev=xcompiler
 	continue
@@ -7254,8 +7535,8 @@
 
       # -msg_* for osf cc
       -msg_*)
-	func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+	func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
 
       # Flags to be passed through unchanged, with rationale:
@@ -7272,12 +7553,17 @@
       # -tp=*                Portland pgcc target processor selection
       # --sysroot=*          for sysroot support
       # -O*, -g*, -flto*, -fwhopr*, -fuse-linker-plugin GCC link-time optimization
+      # -specs=*             GCC specs files
       # -stdlib=*            select c++ std lib with clang
+      # -fsanitize=*         Clang/GCC memory and address sanitizer
+      # -fuse-ld=*           Linker select flags for GCC
+      # -Wa,*                Pass flags directly to the assembler
       -64|-mips[0-9]|-r[0-9][0-9]*|-xarch=*|-xtarget=*|+DA*|+DD*|-q*|-m*| \
       -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*|--sysroot=*| \
-      -O*|-g*|-flto*|-fwhopr*|-fuse-linker-plugin|-fstack-protector*|-stdlib=*)
-        func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+      -O*|-g*|-flto*|-fwhopr*|-fuse-linker-plugin|-fstack-protector*|-stdlib=*| \
+      -specs=*|-fsanitize=*|-fuse-ld=*|-Wa,*)
+        func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
         func_append compile_command " $arg"
         func_append finalize_command " $arg"
         func_append compiler_flags " $arg"
@@ -7298,15 +7584,15 @@
 	  continue
         else
 	  # Otherwise treat like 'Some other compiler flag' below
-	  func_quote_for_eval "$arg"
-	  arg=$func_quote_for_eval_result
+	  func_quote_arg pretty "$arg"
+	  arg=$func_quote_arg_result
         fi
 	;;
 
       # Some other compiler flag.
       -* | +*)
-        func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+        func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
 
       *.$objext)
@@ -7426,8 +7712,8 @@
       *)
 	# Unknown arguments in both finalize_command and compile_command need
 	# to be aesthetically quoted because they are evaled later.
-	func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+	func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
       esac # arg
 
@@ -8632,7 +8918,7 @@
       test CXX = "$tagname" && {
         case $host_os in
         linux*)
-          case `$CC -V 2>&1 | sed 5q` in
+          case `$CC -V 2>&1 | $SED 5q` in
           *Sun\ C*) # Sun C++ 5.9
             func_suncc_cstd_abi
 
@@ -8805,7 +9091,7 @@
 	  #
 	  case $version_type in
 	  # correct linux to gnu/linux during the next big refactor
-	  darwin|freebsd-elf|linux|osf|windows|none)
+	  darwin|freebsd-elf|linux|midnightbsd-elf|osf|windows|none)
 	    func_arith $number_major + $number_minor
 	    current=$func_arith_result
 	    age=$number_minor
@@ -8896,7 +9182,7 @@
 	  versuffix=.$current.$revision
 	  ;;
 
-	freebsd-elf)
+	freebsd-elf | midnightbsd-elf)
 	  func_arith $current - $age
 	  major=.$func_arith_result
 	  versuffix=$major.$age.$revision
@@ -9122,7 +9408,7 @@
 	  *-*-netbsd*)
 	    # Don't link with libc until the a.out ld.so is fixed.
 	    ;;
-	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly*)
+	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-midnightbsd*)
 	    # Do not include libc due to us having libc/libc_r.
 	    ;;
 	  *-*-sco3.2v5* | *-*-sco5v6*)
@@ -9933,8 +10219,8 @@
 	    for cmd in $concat_cmds; do
 	      IFS=$save_ifs
 	      $opt_quiet || {
-		  func_quote_for_expand "$cmd"
-		  eval "func_echo $func_quote_for_expand_result"
+		  func_quote_arg expand,pretty "$cmd"
+		  eval "func_echo $func_quote_arg_result"
 	      }
 	      $opt_dry_run || eval "$cmd" || {
 		lt_exit=$?
@@ -10027,8 +10313,8 @@
 	  eval cmd=\"$cmd\"
 	  IFS=$save_ifs
 	  $opt_quiet || {
-	    func_quote_for_expand "$cmd"
-	    eval "func_echo $func_quote_for_expand_result"
+	    func_quote_arg expand,pretty "$cmd"
+	    eval "func_echo $func_quote_arg_result"
 	  }
 	  $opt_dry_run || eval "$cmd" || {
 	    lt_exit=$?
@@ -10502,12 +10788,13 @@
 	  elif eval var_value=\$$var; test -z "$var_value"; then
 	    relink_command="$var=; export $var; $relink_command"
 	  else
-	    func_quote_for_eval "$var_value"
-	    relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
+	    func_quote_arg pretty "$var_value"
+	    relink_command="$var=$func_quote_arg_result; export $var; $relink_command"
 	  fi
 	done
-	relink_command="(cd `pwd`; $relink_command)"
-	relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+	func_quote eval cd "`pwd`"
+	func_quote_arg pretty,unquoted "($func_quote_result; $relink_command)"
+	relink_command=$func_quote_arg_unquoted_result
       fi
 
       # Only actually do things if not in dry run mode.
@@ -10747,13 +11034,15 @@
 	elif eval var_value=\$$var; test -z "$var_value"; then
 	  relink_command="$var=; export $var; $relink_command"
 	else
-	  func_quote_for_eval "$var_value"
-	  relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
+	  func_quote_arg pretty,unquoted "$var_value"
+	  relink_command="$var=$func_quote_arg_unquoted_result; export $var; $relink_command"
 	fi
       done
       # Quote the link command for shipping.
-      relink_command="(cd `pwd`; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
-      relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+      func_quote eval cd "`pwd`"
+      relink_command="($func_quote_result; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
+      func_quote_arg pretty,unquoted "$relink_command"
+      relink_command=$func_quote_arg_unquoted_result
       if test yes = "$hardcode_automatic"; then
 	relink_command=
       fi
diff --git a/missing b/missing
index 625aeb1..1fe1611 100755
--- a/missing
+++ b/missing
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 # Originally written by Fran,cois Pinard <pinard@iro.umontreal.ca>, 1996.
 
 # This program is free software; you can redistribute it and/or modify
diff --git a/png.5 b/png.5
index c2da95c..20e6aa7 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "April 14, 2019"
+.TH PNG 5 "September 14, 2022"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 
@@ -43,7 +43,7 @@
 https://www.w3.org/TR/REC-png-961001
 
 .SH AUTHORS
-This man page: Cosmin Truta, Glenn Randers-Pehrson
+This man page: Glenn Randers-Pehrson, Cosmin Truta
 .LP
 Portable Network Graphics (PNG) Specification (Second Edition)
 Information technology - Computer graphics and image processing -
@@ -60,7 +60,7 @@
 .LP
 This man page is
 .br
-Copyright (c) 2018-2019 Cosmin Truta.
+Copyright (c) 2018 Cosmin Truta.
 .br
 Copyright (c) 1998-2006 Glenn Randers-Pehrson.
 .br
diff --git a/png.c b/png.c
index 757c755..fc09564 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -14,7 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_37 Your_png_h_is_not_version_1_6_37;
+typedef png_libpng_version_1_6_38 Your_png_h_is_not_version_1_6_38;
 
 #ifdef __GNUC__
 /* The version tests may need to be added to, but the problem warning has
@@ -720,7 +720,7 @@
  *
  * Where UNSIGNED_MAX is the appropriate maximum unsigned value, so when the
  * negative integral value is added the result will be an unsigned value
- * correspnding to the 2's complement representation.
+ * corresponding to the 2's complement representation.
  */
 void PNGAPI
 png_save_int_32(png_bytep buf, png_int_32 i)
@@ -815,8 +815,8 @@
    return PNG_STRING_COPYRIGHT
 #else
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.37" PNG_STRING_NEWLINE \
-      "Copyright (c) 2018-2019 Cosmin Truta" PNG_STRING_NEWLINE \
+      "libpng version 1.6.38" PNG_STRING_NEWLINE \
+      "Copyright (c) 2018-2022 Cosmin Truta" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \
       PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
@@ -1843,12 +1843,12 @@
 #  ifdef PNG_WARNINGS_SUPPORTED
    else
       {
-         char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114*/
+         char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114 */
 
          pos = png_safecat(message, (sizeof message), pos,
              png_format_number(number, number+(sizeof number),
              PNG_NUMBER_FORMAT_x, value));
-         pos = png_safecat(message, (sizeof message), pos, "h: "); /*+2 = 116*/
+         pos = png_safecat(message, (sizeof message), pos, "h: "); /* +2 = 116 */
       }
 #  endif
    /* The 'reason' is an arbitrary message, allow +79 maximum 195 */
diff --git a/png.h b/png.h
index 139eb0d..5fb494f 100644
--- a/png.h
+++ b/png.h
@@ -1,9 +1,9 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.37 - April 14, 2019
+ * libpng version 1.6.38 - September 14, 2022
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -15,7 +15,7 @@
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
  *   libpng versions 0.97, January 1998, through 1.6.35, July 2018:
  *     Glenn Randers-Pehrson
- *   libpng versions 1.6.36, December 2018, through 1.6.37, April 2019:
+ *   libpng versions 1.6.36, December 2018, through 1.6.38, September 2022:
  *     Cosmin Truta
  *   See also "Contributing Authors", below.
  */
@@ -27,8 +27,8 @@
  * PNG Reference Library License version 2
  * ---------------------------------------
  *
- *  * Copyright (c) 1995-2019 The PNG Reference Library Authors.
- *  * Copyright (c) 2018-2019 Cosmin Truta.
+ *  * Copyright (c) 1995-2022 The PNG Reference Library Authors.
+ *  * Copyright (c) 2018-2022 Cosmin Truta.
  *  * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  *  * Copyright (c) 1996-1997 Andreas Dilger.
  *  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -239,7 +239,7 @@
  *    ...
  *    1.5.30                  15    10530  15.so.15.30[.0]
  *    ...
- *    1.6.37                  16    10637  16.so.16.37[.0]
+ *    1.6.38                  16    10638  16.so.16.38[.0]
  *
  *    Henceforth the source version will match the shared-library major and
  *    minor numbers; the shared-library major version number will be used for
@@ -278,8 +278,8 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.37"
-#define PNG_HEADER_VERSION_STRING " libpng version 1.6.37 - April 14, 2019\n"
+#define PNG_LIBPNG_VER_STRING "1.6.38"
+#define PNG_HEADER_VERSION_STRING " libpng version 1.6.38 - September 14, 2022\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
@@ -287,7 +287,7 @@
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   6
-#define PNG_LIBPNG_VER_RELEASE 37
+#define PNG_LIBPNG_VER_RELEASE 38
 
 /* This should be zero for a public release, or non-zero for a
  * development version.  [Deprecated]
@@ -318,7 +318,7 @@
  * From version 1.0.1 it is:
  * XXYYZZ, where XX=major, YY=minor, ZZ=release
  */
-#define PNG_LIBPNG_VER 10637 /* 1.6.37 */
+#define PNG_LIBPNG_VER 10638 /* 1.6.38 */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
@@ -428,7 +428,7 @@
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef char* png_libpng_version_1_6_37;
+typedef char* png_libpng_version_1_6_38;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -1446,7 +1446,7 @@
  * mainly useful for testing, as the defaults should work with most users.
  * Those users who are tight on memory or want faster performance at the
  * expense of compression can modify them.  See the compression library
- * header file (zlib.h) for an explination of the compression functions.
+ * header file (zlib.h) for an explanation of the compression functions.
  */
 
 /* Set the filtering method(s) used by libpng.  Currently, the only valid
@@ -1501,7 +1501,7 @@
  * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
  * (0 - no compression, 9 - "maximal" compression).  Note that tests have
  * shown that zlib compression levels 3-6 usually perform as well as level 9
- * for PNG images, and do considerably fewer caclulations.  In the future,
+ * for PNG images, and do considerably fewer calculations.  In the future,
  * these values may not correspond directly to the zlib compression levels.
  */
 #ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
diff --git a/pngconf.h b/pngconf.h
index 927a769..89d28f8 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,9 +1,9 @@
 
 /* pngconf.h - machine-configurable file for libpng
  *
- * libpng version 1.6.37
+ * libpng version 1.6.38
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2016,2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -180,8 +180,8 @@
  * compiler-specific macros to the values required to change the calling
  * conventions of the various functions.
  */
-#if defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
-    defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+#if defined(_WIN32) || defined(__WIN32__) || defined(__NT__) || \
+    defined(__CYGWIN__)
   /* Windows system (DOS doesn't support DLLs).  Includes builds under Cygwin or
    * MinGW on any architecture currently supported by Windows.  Also includes
    * Watcom builds but these need special treatment because they are not
diff --git a/pngget.c b/pngget.c
index 5abf1ef..e44933c 100644
--- a/pngget.c
+++ b/pngget.c
@@ -1151,7 +1151,7 @@
 
 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
 png_byte PNGAPI
-png_get_rgb_to_gray_status (png_const_structrp png_ptr)
+png_get_rgb_to_gray_status(png_const_structrp png_ptr)
 {
    return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
 }
@@ -1192,27 +1192,27 @@
 /* These functions were added to libpng 1.2.6 and were enabled
  * by default in libpng-1.4.0 */
 png_uint_32 PNGAPI
-png_get_user_width_max (png_const_structrp png_ptr)
+png_get_user_width_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_width_max : 0);
 }
 
 png_uint_32 PNGAPI
-png_get_user_height_max (png_const_structrp png_ptr)
+png_get_user_height_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_height_max : 0);
 }
 
 /* This function was added to libpng 1.4.0 */
 png_uint_32 PNGAPI
-png_get_chunk_cache_max (png_const_structrp png_ptr)
+png_get_chunk_cache_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
 }
 
 /* This function was added to libpng 1.4.1 */
 png_alloc_size_t PNGAPI
-png_get_chunk_malloc_max (png_const_structrp png_ptr)
+png_get_chunk_malloc_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
 }
@@ -1221,13 +1221,13 @@
 /* These functions were added to libpng 1.4.0 */
 #ifdef PNG_IO_STATE_SUPPORTED
 png_uint_32 PNGAPI
-png_get_io_state (png_const_structrp png_ptr)
+png_get_io_state(png_const_structrp png_ptr)
 {
    return png_ptr->io_state;
 }
 
 png_uint_32 PNGAPI
-png_get_io_chunk_type (png_const_structrp png_ptr)
+png_get_io_chunk_type(png_const_structrp png_ptr)
 {
    return png_ptr->chunk_name;
 }
diff --git a/pngpriv.h b/pngpriv.h
index 583c26f..2e426cf 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -1,7 +1,7 @@
 
 /* pngpriv.h - private declarations for use inside libpng
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -174,7 +174,7 @@
 #     else /* !defined __ARM_NEON__ */
          /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
           */
-#        if !defined(__aarch64__)
+#        if !defined(__aarch64__) && !defined(_M_ARM64)
             /* The assembler code currently does not work on ARM64 */
 #          define PNG_ARM_NEON_IMPLEMENTATION 2
 #        endif /* __aarch64__ */
@@ -185,6 +185,8 @@
       /* Use the intrinsics code by default. */
 #     define PNG_ARM_NEON_IMPLEMENTATION 1
 #  endif
+#else /* PNG_ARM_NEON_OPT == 0 */
+#     define PNG_ARM_NEON_IMPLEMENTATION 0
 #endif /* PNG_ARM_NEON_OPT > 0 */
 
 #ifndef PNG_MIPS_MSA_OPT
@@ -263,11 +265,15 @@
 #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
 #     define PNG_MIPS_MSA_IMPLEMENTATION 1
 #  endif
+#else
+#  define PNG_MIPS_MSA_IMPLEMENTATION 0
 #endif /* PNG_MIPS_MSA_OPT > 0 */
 
 #if PNG_POWERPC_VSX_OPT > 0
 #  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
 #  define PNG_POWERPC_VSX_IMPLEMENTATION 1
+#else
+#  define PNG_POWERPC_VSX_IMPLEMENTATION 0
 #endif
 
 
@@ -492,16 +498,7 @@
    static_cast<type>(static_cast<const void*>(value))
 #else
 #  define png_voidcast(type, value) (value)
-#  ifdef _WIN64
-#     ifdef __GNUC__
-         typedef unsigned long long png_ptruint;
-#     else
-         typedef unsigned __int64 png_ptruint;
-#     endif
-#  else
-      typedef unsigned long png_ptruint;
-#  endif
-#  define png_constcast(type, value) ((type)(png_ptruint)(const void*)(value))
+#  define png_constcast(type, value) ((type)(void*)(const void*)(value))
 #  define png_aligncast(type, value) ((void*)(value))
 #  define png_aligncastconst(type, value) ((const void*)(value))
 #endif /* __cplusplus */
@@ -543,9 +540,8 @@
 #  include <alloc.h>
 #endif
 
-#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
-    defined(_WIN32) || defined(__WIN32__)
-#  include <windows.h>  /* defines _WINDOWS_ macro */
+#if defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
+#  include <windows.h>
 #endif
 #endif /* PNG_VERSION_INFO_ONLY */
 
@@ -554,24 +550,20 @@
  * functions that are passed far data must be model-independent.
  */
 
-/* Memory model/platform independent fns */
+/* Platform-independent functions */
 #ifndef PNG_ABORT
-#  ifdef _WINDOWS_
-#    define PNG_ABORT() ExitProcess(0)
-#  else
-#    define PNG_ABORT() abort()
-#  endif
+#  define PNG_ABORT() abort()
 #endif
 
 /* These macros may need to be architecture dependent. */
-#define PNG_ALIGN_NONE   0 /* do not use data alignment */
-#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
+#define PNG_ALIGN_NONE      0 /* do not use data alignment */
+#define PNG_ALIGN_ALWAYS    1 /* assume unaligned accesses are OK */
 #ifdef offsetof
-#  define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
+#  define PNG_ALIGN_OFFSET  2 /* use offsetof to determine alignment */
 #else
 #  define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
 #endif
-#define PNG_ALIGN_SIZE   3 /* use sizeof to determine alignment */
+#define PNG_ALIGN_SIZE      3 /* use sizeof to determine alignment */
 
 #ifndef PNG_ALIGN_TYPE
    /* Default to using aligned access optimizations and requiring alignment to a
@@ -585,26 +577,25 @@
    /* This is used because in some compiler implementations non-aligned
     * structure members are supported, so the offsetof approach below fails.
     * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
-    * is good for performance.  Do not do this unless you have tested the result
-    * and understand it.
+    * is good for performance.  Do not do this unless you have tested the
+    * result and understand it.
     */
-#  define png_alignof(type) (sizeof (type))
+#  define png_alignof(type) (sizeof(type))
 #else
 #  if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
-#     define png_alignof(type) offsetof(struct{char c; type t;}, t)
+#    define png_alignof(type) offsetof(struct{char c; type t;}, t)
 #  else
-#     if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
-#        define png_alignof(type) (1)
-#     endif
-      /* Else leave png_alignof undefined to prevent use thereof */
+#    if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
+#      define png_alignof(type) 1
+#    endif
+     /* Else leave png_alignof undefined to prevent use thereof */
 #  endif
 #endif
 
-/* This implicitly assumes alignment is always to a power of 2. */
+/* This implicitly assumes alignment is always a multiple of 2. */
 #ifdef png_alignof
-#  define png_isaligned(ptr, type)\
-   (((type)((const char*)ptr-(const char*)0) & \
-   (type)(png_alignof(type)-1)) == 0)
+#  define png_isaligned(ptr, type) \
+   (((type)(size_t)((const void*)(ptr)) & (type)(png_alignof(type)-1)) == 0)
 #else
 #  define png_isaligned(ptr, type) 0
 #endif
diff --git a/pngread.c b/pngread.c
index 8fa7d9f..5ab9224 100644
--- a/pngread.c
+++ b/pngread.c
@@ -3452,7 +3452,6 @@
 
             for (pass = 0; pass < passes; ++pass)
             {
-               png_bytep row = png_voidcast(png_bytep, display->first_row);
                unsigned int     startx, stepx, stepy;
                png_uint_32      y;
 
@@ -3557,8 +3556,6 @@
 
                         inrow += 2; /* gray and alpha channel */
                      }
-
-                     row += display->row_bytes;
                   }
                }
             }
diff --git a/pngrtran.c b/pngrtran.c
index 9a8fad9..238f5af 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -21,7 +21,7 @@
 #ifdef PNG_ARM_NEON_IMPLEMENTATION
 #  if PNG_ARM_NEON_IMPLEMENTATION == 1
 #    define PNG_ARM_NEON_INTRINSICS_AVAILABLE
-#    if defined(_MSC_VER) && defined(_M_ARM64)
+#    if defined(_MSC_VER) && !defined(__clang__) && defined(_M_ARM64)
 #      include <arm64_neon.h>
 #    else
 #      include <arm_neon.h>
diff --git a/pngrutil.c b/pngrutil.c
index d5fa08c..ca060dd 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -302,7 +302,6 @@
    if (buffer != NULL && new_size > png_ptr->read_buffer_size)
    {
       png_ptr->read_buffer = NULL;
-      png_ptr->read_buffer = NULL;
       png_ptr->read_buffer_size = 0;
       png_free(png_ptr, buffer);
       buffer = NULL;
@@ -2076,21 +2075,22 @@
       png_byte buf[1];
       png_crc_read(png_ptr, buf, 1);
       info_ptr->eXIf_buf[i] = buf[0];
-      if (i == 1 && buf[0] != 'M' && buf[0] != 'I'
-                 && info_ptr->eXIf_buf[0] != buf[0])
+      if (i == 1)
       {
-         png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "incorrect byte-order specifier");
-         png_free(png_ptr, info_ptr->eXIf_buf);
-         info_ptr->eXIf_buf = NULL;
-         return;
+         if ((buf[0] != 'M' && buf[0] != 'I') ||
+             (info_ptr->eXIf_buf[0] != buf[0]))
+         {
+            png_crc_finish(png_ptr, length - 2);
+            png_chunk_benign_error(png_ptr, "incorrect byte-order specifier");
+            png_free(png_ptr, info_ptr->eXIf_buf);
+            info_ptr->eXIf_buf = NULL;
+            return;
+         }
       }
    }
 
-   if (png_crc_finish(png_ptr, 0) != 0)
-      return;
-
-   png_set_eXIf_1(png_ptr, info_ptr, length, info_ptr->eXIf_buf);
+   if (png_crc_finish(png_ptr, 0) == 0)
+      png_set_eXIf_1(png_ptr, info_ptr, length, info_ptr->eXIf_buf);
 
    png_free(png_ptr, info_ptr->eXIf_buf);
    info_ptr->eXIf_buf = NULL;
@@ -2126,8 +2126,9 @@
 
    num = length / 2 ;
 
-   if (num != (unsigned int) png_ptr->num_palette ||
-       num > (unsigned int) PNG_MAX_PALETTE_LENGTH)
+   if (length != num * 2 ||
+       num != (unsigned int)png_ptr->num_palette ||
+       num > (unsigned int)PNG_MAX_PALETTE_LENGTH)
    {
       png_crc_finish(png_ptr, length);
       png_chunk_benign_error(png_ptr, "invalid");
@@ -4621,14 +4622,13 @@
        */
       {
          png_bytep temp = png_ptr->big_row_buf + 32;
-         int extra = (int)((temp - (png_bytep)0) & 0x0f);
+         size_t extra = (size_t)temp & 0x0f;
          png_ptr->row_buf = temp - extra - 1/*filter byte*/;
 
          temp = png_ptr->big_prev_row + 32;
-         extra = (int)((temp - (png_bytep)0) & 0x0f);
+         extra = (size_t)temp & 0x0f;
          png_ptr->prev_row = temp - extra - 1/*filter byte*/;
       }
-
 #else
       /* Use 31 bytes of padding before and 17 bytes after row_buf. */
       png_ptr->row_buf = png_ptr->big_row_buf + 31;
diff --git a/pngset.c b/pngset.c
index ec75dbe..8c372cf 100644
--- a/pngset.c
+++ b/pngset.c
@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -1019,6 +1019,9 @@
           info_ptr->trans_alpha = png_voidcast(png_bytep,
               png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
           memcpy(info_ptr->trans_alpha, trans_alpha, (size_t)num_trans);
+
+          info_ptr->valid |= PNG_INFO_tRNS;
+          info_ptr->free_me |= PNG_FREE_TRNS;
        }
        png_ptr->trans_alpha = info_ptr->trans_alpha;
    }
@@ -1326,7 +1329,7 @@
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
 png_uint_32 PNGAPI
-png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
+png_permit_mng_features(png_structrp png_ptr, png_uint_32 mng_features)
 {
    png_debug(1, "in png_permit_mng_features");
 
@@ -1633,7 +1636,7 @@
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
 /* This function was added to libpng 1.2.6 */
 void PNGAPI
-png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
+png_set_user_limits(png_structrp png_ptr, png_uint_32 user_width_max,
     png_uint_32 user_height_max)
 {
    /* Images with dimensions larger than these limits will be
@@ -1649,7 +1652,7 @@
 
 /* This function was added to libpng 1.4.0 */
 void PNGAPI
-png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
+png_set_chunk_cache_max(png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
 {
    if (png_ptr != NULL)
       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
@@ -1657,7 +1660,7 @@
 
 /* This function was added to libpng 1.4.1 */
 void PNGAPI
-png_set_chunk_malloc_max (png_structrp png_ptr,
+png_set_chunk_malloc_max(png_structrp png_ptr,
     png_alloc_size_t user_chunk_malloc_max)
 {
    if (png_ptr != NULL)
diff --git a/pngstruct.h b/pngstruct.h
index 8bdc7ce..e591d94 100644
--- a/pngstruct.h
+++ b/pngstruct.h
@@ -1,7 +1,7 @@
 
 /* pngstruct.h - header file for PNG reference library
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -334,18 +334,8 @@
    size_t current_buffer_size;       /* amount of data now in current_buffer */
    int process_mode;                 /* what push library is currently doing */
    int cur_palette;                  /* current push library palette index */
-
 #endif /* PROGRESSIVE_READ */
 
-#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
-/* For the Borland special 64K segment handler */
-   png_bytepp offset_table_ptr;
-   png_bytep offset_table;
-   png_uint_16 offset_table_number;
-   png_uint_16 offset_table_count;
-   png_uint_16 offset_table_count_free;
-#endif
-
 #ifdef PNG_READ_QUANTIZE_SUPPORTED
    png_bytep palette_lookup; /* lookup table for quantizing */
    png_bytep quantize_index; /* index translation for palette files */
diff --git a/pngtest.c b/pngtest.c
index a715ae1..6f18300 100644
--- a/pngtest.c
+++ b/pngtest.c
@@ -2155,4 +2155,4 @@
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_37 Your_png_h_is_not_version_1_6_37;
+typedef png_libpng_version_1_6_38 Your_png_h_is_not_version_1_6_38;
diff --git a/pngwrite.c b/pngwrite.c
index 59377a4..06c45d1 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1,7 +1,7 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -489,6 +489,16 @@
    png_debug(1, "in png_convert_from_time_t");
 
    tbuf = gmtime(&ttime);
+   if (tbuf == NULL)
+   {
+      /* TODO: add a safe function which takes a png_ptr argument and raises
+       * a png_error if the ttime argument is invalid and the call to gmtime
+       * fails as a consequence.
+       */
+      memset(ptime, 0, sizeof(*ptime));
+      return;
+   }
+
    png_convert_from_struct_tm(ptime, tbuf);
 }
 #endif
diff --git a/projects/vstudio/README.txt b/projects/vstudio/README.txt
index e28ec95..53f6b59 100644
--- a/projects/vstudio/README.txt
+++ b/projects/vstudio/README.txt
@@ -1,7 +1,7 @@
 Instructions for building libpng using Microsoft Visual Studio
 ==============================================================
 
-Copyright (c) 2018 Cosmin Truta
+Copyright (c) 2018,2022 Cosmin Truta
 Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
 
 This code is released under the libpng license.
@@ -9,9 +9,9 @@
 in png.h
 
 This directory contains a solution for building libpng under Microsoft
-Visual Studio 2010.  It may also work under later versions of Visual
-Studio.  You should be familiar with Visual Studio before using this
-solution.
+Visual Studio 2019.  It may also work under earlier or later versions
+of Visual Studio.  You should be familiar with Visual Studio before
+using this solution.
 
 Initial preparations
 --------------------
diff --git a/projects/vstudio/libpng/libpng.vcxproj b/projects/vstudio/libpng/libpng.vcxproj
index 9bfb718..e10f4ff 100644
--- a/projects/vstudio/libpng/libpng.vcxproj
+++ b/projects/vstudio/libpng/libpng.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -29,19 +45,45 @@
     <ConfigurationType>DynamicLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
     <WholeProgramOptimization>true</WholeProgramOptimization>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>DynamicLibrary</ConfigurationType>
     <WholeProgramOptimization>true</WholeProgramOptimization>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -49,15 +91,27 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
@@ -65,22 +119,42 @@
     </CustomBuildBeforeTargets>
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets>
     </CustomBuildBeforeTargets>
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
@@ -88,7 +162,37 @@
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <Optimization>Disabled</Optimization>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>zlib.lib</AdditionalDependencies>
+      <Version>16</Version>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <FloatingPointExceptions>false</FloatingPointExceptions>
@@ -114,12 +218,12 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <FloatingPointExceptions>false</FloatingPointExceptions>
@@ -130,7 +234,34 @@
       <StringPooling>true</StringPooling>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -145,7 +276,37 @@
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <Optimization>Full</Optimization>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>zlib.lib</AdditionalDependencies>
+      <Version>16</Version>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <FloatingPointExceptions>false</FloatingPointExceptions>
       <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
       <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
@@ -170,13 +331,13 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <PrecompiledHeader>Use</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <FloatingPointExceptions>false</FloatingPointExceptions>
       <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
       <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
@@ -186,7 +347,39 @@
       <MinimalRebuild>false</MinimalRebuild>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <Optimization>Full</Optimization>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <Optimization>Full</Optimization>
       <WholeProgramOptimization>true</WholeProgramOptimization>
     </ClCompile>
@@ -201,11 +394,40 @@
     </Lib>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClCompile Include="..\..\..\arm\arm_init.c">
+      <DeploymentContent>true</DeploymentContent>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="..\..\..\arm\filter_neon_intrinsics.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="..\..\..\arm\palette_neon_intrinsics.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
     <ClCompile Include="..\..\..\png.c">
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">Create</PrecompiledHeader>
     </ClCompile>
     <ClCompile Include="..\..\..\pngerror.c" />
     <ClCompile Include="..\..\..\pngget.c" />
@@ -225,7 +447,9 @@
   <ItemGroup>
     <ResourceCompile Include="..\..\..\scripts\pngwin.rc">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">true</ExcludedFromBuild>
     </ResourceCompile>
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
diff --git a/projects/vstudio/pnglibconf/pnglibconf.vcxproj b/projects/vstudio/pnglibconf/pnglibconf.vcxproj
index efcc440..e0a3887 100644
--- a/projects/vstudio/pnglibconf/pnglibconf.vcxproj
+++ b/projects/vstudio/pnglibconf/pnglibconf.vcxproj
@@ -1,6 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -16,6 +20,14 @@
     <UseDebugLibraries>false</UseDebugLibraries>
     <WholeProgramOptimization>true</WholeProgramOptimization>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(SolutionDir)\zlib.props" />
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
@@ -24,10 +36,16 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <CustomBuildBeforeTargets>Build</CustomBuildBeforeTargets>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <CustomBuildBeforeTargets>Build</CustomBuildBeforeTargets>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
@@ -53,6 +71,31 @@
       <Inputs>..\..\..\scripts\pnglibconf.h.prebuilt</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <Optimization>MaxSpeed</Optimization>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <CustomBuildStep>
+      <Command>copy ..\..\..\scripts\pnglibconf.h.prebuilt ..\..\..\pnglibconf.h</Command>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Message>Generating pnglibconf.h</Message>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Outputs>..\..\..\pnglibconf.h</Outputs>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Inputs>..\..\..\scripts\pnglibconf.h.prebuilt</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
   <ItemGroup>
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
diff --git a/projects/vstudio/pngstest/pngstest.vcxproj b/projects/vstudio/pngstest/pngstest.vcxproj
index 21810e3..3937cb4 100644
--- a/projects/vstudio/pngstest/pngstest.vcxproj
+++ b/projects/vstudio/pngstest/pngstest.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngstest.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngtest/pngtest.vcxproj b/projects/vstudio/pngtest/pngtest.vcxproj
index f1df07d..72beced 100644
--- a/projects/vstudio/pngtest/pngtest.vcxproj
+++ b/projects/vstudio/pngtest/pngtest.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,44 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>$(OutDir)pngtest.exe ..\..\..\pngtest.png $(IntDir)pngout.png</Command>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngunknown/pngunknown.vcxproj b/projects/vstudio/pngunknown/pngunknown.vcxproj
index 409d662..f4d130d 100644
--- a/projects/vstudio/pngunknown/pngunknown.vcxproj
+++ b/projects/vstudio/pngunknown/pngunknown.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngunknown.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngvalid/pngvalid.vcxproj b/projects/vstudio/pngvalid/pngvalid.vcxproj
index c117d29..3726193 100644
--- a/projects/vstudio/pngvalid/pngvalid.vcxproj
+++ b/projects/vstudio/pngvalid/pngvalid.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngvalid.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/vstudio.sln b/projects/vstudio/vstudio.sln
index af0b1ba..5fc1c29 100644
--- a/projects/vstudio/vstudio.sln
+++ b/projects/vstudio/vstudio.sln
@@ -1,5 +1,7 @@
-Microsoft Visual Studio Solution File, Format Version 11.00
-# Visual Studio 2010
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.31515.178
+MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlib", "zlib\zlib.vcxproj", "{60F89955-91C6-3A36-8000-13C592FEC2DF}"
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "pnglibconf", "pnglibconf\pnglibconf.vcxproj", "{EB33566E-DA7F-4D28-9077-88C0B7C77E35}"
@@ -40,70 +42,133 @@
 EndProject
 Global
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 		Debug Library|Win32 = Debug Library|Win32
+		Debug|ARM64 = Debug|ARM64
 		Debug|Win32 = Debug|Win32
+		Release Library|ARM64 = Release Library|ARM64
 		Release Library|Win32 = Release Library|Win32
+		Release|ARM64 = Release|ARM64
 		Release|Win32 = Release|Win32
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
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-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.Build.0 = Debug Library|Win32
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-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.Build.0 = Release|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|ARM64.Build.0 = Debug|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|Win32.ActiveCfg = Debug|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|Win32.Build.0 = Debug|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|Win32.Build.0 = Release Library|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|ARM64.ActiveCfg = Release|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|ARM64.Build.0 = Release|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|Win32.ActiveCfg = Release|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|Win32.Build.0 = Release|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.Build.0 = Debug Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.ActiveCfg = Debug|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.Build.0 = Debug|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.ActiveCfg = Release Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.Build.0 = Release Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.ActiveCfg = Release|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|Win32.Build.0 = Release|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|ARM64.Build.0 = Debug|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.ActiveCfg = Debug|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.Build.0 = Debug|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.Build.0 = Release Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|ARM64.ActiveCfg = Release|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|ARM64.Build.0 = Release|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.ActiveCfg = Release|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.Build.0 = Release|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|ARM64.Build.0 = Debug|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.ActiveCfg = Debug|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.Build.0 = Debug|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.Build.0 = Release Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|ARM64.ActiveCfg = Release|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|ARM64.Build.0 = Release|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.ActiveCfg = Release|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.Build.0 = Release|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|ARM64.Build.0 = Debug|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.ActiveCfg = Debug|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.Build.0 = Debug|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.Build.0 = Release Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|ARM64.ActiveCfg = Release|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|ARM64.Build.0 = Release|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.ActiveCfg = Release|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.Build.0 = Release|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|ARM64.Build.0 = Debug|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|Win32.ActiveCfg = Debug|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|Win32.Build.0 = Debug|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|Win32.Build.0 = Release Library|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|ARM64.ActiveCfg = Release|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|ARM64.Build.0 = Release|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|Win32.ActiveCfg = Release|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|Win32.Build.0 = Release|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|ARM64.Build.0 = Debug|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|Win32.ActiveCfg = Debug|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|Win32.Build.0 = Debug|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|Win32.Build.0 = Release Library|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|ARM64.ActiveCfg = Release|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|ARM64.Build.0 = Release|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|Win32.ActiveCfg = Release|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|Win32.Build.0 = Release|Win32
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {785775C5-509E-4727-A290-F1B65E1B68B2}
+	EndGlobalSection
 EndGlobal
diff --git a/projects/vstudio/zlib/zlib.vcxproj b/projects/vstudio/zlib/zlib.vcxproj
index 0df16db..23e6065 100644
--- a/projects/vstudio/zlib/zlib.vcxproj
+++ b/projects/vstudio/zlib/zlib.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -40,18 +56,41 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -59,42 +98,69 @@
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -102,16 +168,33 @@
       <SubSystem>Windows</SubSystem>
     </Link>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
     <ClCompile>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <ClCompile>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -120,9 +203,26 @@
       <SubSystem>Windows</SubSystem>
     </Link>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -131,9 +231,9 @@
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -144,6 +244,29 @@
       <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
     </Lib>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
@@ -156,7 +279,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
       <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -169,6 +292,30 @@
       <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
     </Lib>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
diff --git a/scripts/README.txt b/scripts/README.txt
index 3d911ef..f7bceec 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -75,5 +75,5 @@
  macro.lst         =>  Used by autoconf tools
  prefix.dfn        =>  Used by autoconf tools
 
-
-Further information can be found in comments in the individual makefiles.
+Further information can be found in comments in the individual scripts and
+makefiles.
diff --git a/scripts/descrip.mms b/scripts/descrip.mms
index a3aefbf..c440fc3 100644
--- a/scripts/descrip.mms
+++ b/scripts/descrip.mms
@@ -6,14 +6,11 @@
 pref = /prefix=all
 .endif
 
+OBJS = png.obj, pngerror.obj, pngget.obj, pngmem.obj, pngpread.obj,\
+       pngread.obj, pngrio.obj, pngrtran.obj, pngrutil.obj, pngset.obj,\
+       pngtrans.obj, pngwio.obj, pngwrite.obj, pngwtran.obj, pngwutil.obj
 
-
-OBJS = png.obj, pngset.obj, pngget.obj, pngrutil.obj, pngtrans.obj,\
-	pngwutil.obj, pngread.obj, pngmem.obj, pngwrite.obj, pngrtran.obj,\
-	pngwtran.obj, pngrio.obj, pngwio.obj, pngerror.obj, pngpread.obj
-
-
-CFLAGS= $(C_DEB) $(CC_DEFS) $(PREF)
+CFLAGS = $(C_DEB) $(CC_DEFS) $(PREF)
 
 all : pngtest.exe libpng.olb
 	@ write sys$output " pngtest available"
@@ -21,32 +18,30 @@
 libpng.olb : libpng.olb($(OBJS))
 	@ write sys$output " libpng available"
 
-
 pngtest.exe : pngtest.obj libpng.olb
-              link pngtest,libpng.olb/lib,$(ZLIBSRC)libz.olb/lib
+	link pngtest,libpng.olb/lib,$(ZLIBSRC)libz.olb/lib
 
 test : pngtest.exe
-   run pngtest
+	run pngtest
 
 clean :
 	delete *.obj;*,*.exe;
 
-
 # Other dependencies.
-png.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+png.obj :      png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngget.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngmem.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngpread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngset.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngget.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngread.obj :  png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngrio.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngrtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngrutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngmem.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngrio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngwio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngset.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngtrans.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngwio.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwrite.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 
-pngtest.obj : png.h, pngconf.h, pnglibconf.h
+pngtest.obj :  png.h, pngconf.h, pnglibconf.h
diff --git a/scripts/dfn.awk b/scripts/dfn.awk
index 346b9db..0dc99df 100755
--- a/scripts/dfn.awk
+++ b/scripts/dfn.awk
Binary files differ
diff --git a/scripts/genchk.cmake.in b/scripts/genchk.cmake.in
index ab3b9d7..1b6aa84 100644
--- a/scripts/genchk.cmake.in
+++ b/scripts/genchk.cmake.in
@@ -10,6 +10,7 @@
 
 # Variables substituted from CMakeLists.txt
 set(SRCDIR "@CMAKE_CURRENT_SOURCE_DIR@")
+set(BINDIR "@CMAKE_CURRENT_BINARY_DIR@")
 
 set(AWK "@AWK@")
 
@@ -23,7 +24,7 @@
 if("${INPUTEXT}" STREQUAL ".out" AND "${OUTPUTEXT}" STREQUAL ".chk")
   # Generate .chk from .out with awk (generic)
   file(REMOVE "${OUTPUT}" "${OUTPUTDIR}/${OUTPUTBASE}.new")
-  execute_process(COMMAND "${AWK}" -f "${SRCDIR}/scripts/checksym.awk"
+  execute_process(COMMAND "${AWK}" -f "${BINDIR}/scripts/checksym.awk"
                           "${SRCDIR}/scripts/${INPUTBASE}.def"
                           "of=${OUTPUTDIR}/${OUTPUTBASE}.new"
                           "${INPUT}"
diff --git a/scripts/libpng-config-head.in b/scripts/libpng-config-head.in
index 2a5afb4..028c3b8 100644
--- a/scripts/libpng-config-head.in
+++ b/scripts/libpng-config-head.in
@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.6.37
+version=1.6.38
 prefix=""
 libdir=""
 libs=""
diff --git a/scripts/libpng.pc.in b/scripts/libpng.pc.in
index 416fefe..70ae041 100644
--- a/scripts/libpng.pc.in
+++ b/scripts/libpng.pc.in
@@ -5,6 +5,6 @@
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.6.37
+Version: 1.6.38
 Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}
diff --git a/scripts/libtool.m4 b/scripts/libtool.m4
index a3bc337..79a2451 100644
--- a/scripts/libtool.m4
+++ b/scripts/libtool.m4
@@ -1,6 +1,7 @@
 # libtool.m4 - Configure libtool for the host system. -*-Autoconf-*-
 #
-#   Copyright (C) 1996-2001, 2003-2015 Free Software Foundation, Inc.
+#   Copyright (C) 1996-2001, 2003-2019, 2021-2022 Free Software
+#   Foundation, Inc.
 #   Written by Gordon Matzigkeit, 1996
 #
 # This file is free software; the Free Software Foundation gives
@@ -31,7 +32,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ])
 
-# serial 58 LT_INIT
+# serial 59 LT_INIT
 
 
 # LT_PREREQ(VERSION)
@@ -181,6 +182,7 @@
 m4_require([_LT_CHECK_SHELL_FEATURES])dnl
 m4_require([_LT_PATH_CONVERSION_FUNCTIONS])dnl
 m4_require([_LT_CMD_RELOAD])dnl
+m4_require([_LT_DECL_FILECMD])dnl
 m4_require([_LT_CHECK_MAGIC_METHOD])dnl
 m4_require([_LT_CHECK_SHAREDLIB_FROM_LINKLIB])dnl
 m4_require([_LT_CMD_OLD_ARCHIVE])dnl
@@ -219,8 +221,8 @@
 ofile=libtool
 can_build_shared=yes
 
-# All known linkers require a '.a' archive for static linking (except MSVC,
-# which needs '.lib').
+# All known linkers require a '.a' archive for static linking (except MSVC and
+# ICC, which need '.lib').
 libext=a
 
 with_gnu_ld=$lt_cv_prog_gnu_ld
@@ -778,7 +780,7 @@
   # if finds mixed CR/LF and LF-only lines.  Since sed operates in
   # text mode, it properly converts lines to CR/LF.  This bash problem
   # is reportedly fixed, but why not run on old versions too?
-  sed '$q' "$ltmain" >> "$cfgfile" \
+  $SED '$q' "$ltmain" >> "$cfgfile" \
      || (rm -f "$cfgfile"; exit 1)
 
    mv -f "$cfgfile" "$ofile" ||
@@ -1042,8 +1044,8 @@
 _LT_EOF
       echo "$LTCC $LTCFLAGS -c -o conftest.o conftest.c" >&AS_MESSAGE_LOG_FD
       $LTCC $LTCFLAGS -c -o conftest.o conftest.c 2>&AS_MESSAGE_LOG_FD
-      echo "$AR cru libconftest.a conftest.o" >&AS_MESSAGE_LOG_FD
-      $AR cru libconftest.a conftest.o 2>&AS_MESSAGE_LOG_FD
+      echo "$AR $AR_FLAGS libconftest.a conftest.o" >&AS_MESSAGE_LOG_FD
+      $AR $AR_FLAGS libconftest.a conftest.o 2>&AS_MESSAGE_LOG_FD
       echo "$RANLIB libconftest.a" >&AS_MESSAGE_LOG_FD
       $RANLIB libconftest.a 2>&AS_MESSAGE_LOG_FD
       cat > conftest.c << _LT_EOF
@@ -1067,17 +1069,12 @@
       _lt_dar_allow_undefined='$wl-undefined ${wl}suppress' ;;
     darwin1.*)
       _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-    darwin*) # darwin 5.x on
-      # if running on 10.5 or later, the deployment target defaults
-      # to the OS version, if on x86, and 10.4, the deployment
-      # target defaults to 10.4. Don't you love it?
-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
-	10.0,*86*-darwin8*|10.0,*-darwin[[91]]*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
-	10.[[012]][[,.]]*)
-	  _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-	10.*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+    darwin*)
+      case $MACOSX_DEPLOYMENT_TARGET,$host in
+        10.[[012]],*|,*powerpc*-darwin[[5-8]]*)
+          _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+        *)
+          _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
       esac
     ;;
   esac
@@ -1126,12 +1123,12 @@
     output_verbose_link_cmd=func_echo_all
     _LT_TAGVAR(archive_cmds, $1)="\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dsymutil"
     _LT_TAGVAR(module_cmds, $1)="\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dsymutil"
-    _LT_TAGVAR(archive_expsym_cmds, $1)="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
-    _LT_TAGVAR(module_expsym_cmds, $1)="sed -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
+    _LT_TAGVAR(archive_expsym_cmds, $1)="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
+    _LT_TAGVAR(module_expsym_cmds, $1)="$SED -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
     m4_if([$1], [CXX],
 [   if test yes != "$lt_cv_apple_cc_single_mod"; then
       _LT_TAGVAR(archive_cmds, $1)="\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dsymutil"
-      _LT_TAGVAR(archive_expsym_cmds, $1)="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dar_export_syms$_lt_dsymutil"
+      _LT_TAGVAR(archive_expsym_cmds, $1)="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dar_export_syms$_lt_dsymutil"
     fi
 ],[])
   else
@@ -1245,7 +1242,8 @@
 # _LT_WITH_SYSROOT
 # ----------------
 AC_DEFUN([_LT_WITH_SYSROOT],
-[AC_MSG_CHECKING([for sysroot])
+[m4_require([_LT_DECL_SED])dnl
+AC_MSG_CHECKING([for sysroot])
 AC_ARG_WITH([sysroot],
 [AS_HELP_STRING([--with-sysroot@<:@=DIR@:>@],
   [Search for dependent libraries within DIR (or the compiler's sysroot
@@ -1262,7 +1260,7 @@
    fi
    ;; #(
  /*)
-   lt_sysroot=`echo "$with_sysroot" | sed -e "$sed_quote_subst"`
+   lt_sysroot=`echo "$with_sysroot" | $SED -e "$sed_quote_subst"`
    ;; #(
  no|'')
    ;; #(
@@ -1292,7 +1290,7 @@
   # options accordingly.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *ELF-32*)
 	HPUX_IA64_MODE=32
 	;;
@@ -1309,7 +1307,7 @@
   echo '[#]line '$LINENO' "configure"' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
     if test yes = "$lt_cv_prog_gnu_ld"; then
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -melf32bsmip"
 	  ;;
@@ -1321,7 +1319,7 @@
 	;;
       esac
     else
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -32"
 	  ;;
@@ -1343,7 +1341,7 @@
   echo '[#]line '$LINENO' "configure"' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
     emul=elf
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *32-bit*)
 	emul="${emul}32"
 	;;
@@ -1351,7 +1349,7 @@
 	emul="${emul}64"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *MSB*)
 	emul="${emul}btsmip"
 	;;
@@ -1359,7 +1357,7 @@
 	emul="${emul}ltsmip"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *N32*)
 	emul="${emul}n32"
 	;;
@@ -1379,14 +1377,14 @@
   # not appear in the list.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
       *32-bit*)
 	case $host in
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
 	  x86_64-*linux*)
-	    case `/usr/bin/file conftest.o` in
+	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
 		;;
@@ -1454,7 +1452,7 @@
   # options accordingly.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
     *64-bit*)
       case $lt_cv_prog_gnu_ld in
       yes*)
@@ -1493,9 +1491,22 @@
 m4_defun([_LT_PROG_AR],
 [AC_CHECK_TOOLS(AR, [ar], false)
 : ${AR=ar}
-: ${AR_FLAGS=cru}
 _LT_DECL([], [AR], [1], [The archiver])
-_LT_DECL([], [AR_FLAGS], [1], [Flags to create an archive])
+
+# Use ARFLAGS variable as AR's operation code to sync the variable naming with
+# Automake.  If both AR_FLAGS and ARFLAGS are specified, AR_FLAGS should have
+# higher priority because thats what people were doing historically (setting
+# ARFLAGS for automake and AR_FLAGS for libtool).  FIXME: Make the AR_FLAGS
+# variable obsoleted/removed.
+
+test ${AR_FLAGS+y} || AR_FLAGS=${ARFLAGS-cr}
+lt_ar_flags=$AR_FLAGS
+_LT_DECL([], [lt_ar_flags], [0], [Flags to create an archive (by configure)])
+
+# Make AR_FLAGS overridable by 'make ARFLAGS='.  Don't try to run-time override
+# by AR_FLAGS because that was never working and AR_FLAGS is about to die.
+_LT_DECL([], [AR_FLAGS], [\@S|@{ARFLAGS-"\@S|@lt_ar_flags"}],
+         [Flags to create an archive])
 
 AC_CACHE_CHECK([for archiver @FILE support], [lt_cv_ar_at_file],
   [lt_cv_ar_at_file=no
@@ -1714,7 +1725,7 @@
     lt_cv_sys_max_cmd_len=8192;
     ;;
 
-  bitrig* | darwin* | dragonfly* | freebsd* | netbsd* | openbsd*)
+  bitrig* | darwin* | dragonfly* | freebsd* | midnightbsd* | netbsd* | openbsd*)
     # This has been around since 386BSD, at least.  Likely further.
     if test -x /sbin/sysctl; then
       lt_cv_sys_max_cmd_len=`/sbin/sysctl -n kern.argmax`
@@ -1757,7 +1768,7 @@
   sysv5* | sco5v6* | sysv4.2uw2*)
     kargmax=`grep ARG_MAX /etc/conf/cf.d/stune 2>/dev/null`
     if test -n "$kargmax"; then
-      lt_cv_sys_max_cmd_len=`echo $kargmax | sed 's/.*[[	 ]]//'`
+      lt_cv_sys_max_cmd_len=`echo $kargmax | $SED 's/.*[[	 ]]//'`
     else
       lt_cv_sys_max_cmd_len=32768
     fi
@@ -2207,26 +2218,35 @@
 striplib=
 old_striplib=
 AC_MSG_CHECKING([whether stripping libraries is possible])
-if test -n "$STRIP" && $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
-  test -z "$old_striplib" && old_striplib="$STRIP --strip-debug"
-  test -z "$striplib" && striplib="$STRIP --strip-unneeded"
-  AC_MSG_RESULT([yes])
+if test -z "$STRIP"; then
+  AC_MSG_RESULT([no])
 else
-# FIXME - insert some real tests, host_os isn't really good enough
-  case $host_os in
-  darwin*)
-    if test -n "$STRIP"; then
+  if $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
+    old_striplib="$STRIP --strip-debug"
+    striplib="$STRIP --strip-unneeded"
+    AC_MSG_RESULT([yes])
+  else
+    case $host_os in
+    darwin*)
+      # FIXME - insert some real tests, host_os isn't really good enough
       striplib="$STRIP -x"
       old_striplib="$STRIP -S"
       AC_MSG_RESULT([yes])
-    else
+      ;;
+    freebsd*)
+      if $STRIP -V 2>&1 | $GREP "elftoolchain" >/dev/null; then
+        old_striplib="$STRIP --strip-debug"
+        striplib="$STRIP --strip-unneeded"
+        AC_MSG_RESULT([yes])
+      else
+        AC_MSG_RESULT([no])
+      fi
+      ;;
+    *)
       AC_MSG_RESULT([no])
-    fi
-    ;;
-  *)
-    AC_MSG_RESULT([no])
-    ;;
-  esac
+      ;;
+    esac
+  fi
 fi
 _LT_DECL([], [old_striplib], [1], [Commands to strip libraries])
 _LT_DECL([], [striplib], [1])
@@ -2549,7 +2569,7 @@
     case $host_os in
     cygwin*)
       # Cygwin DLLs use 'cyg' prefix rather than 'lib'
-      soname_spec='`echo $libname | sed -e 's/^lib/cyg/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
+      soname_spec='`echo $libname | $SED -e 's/^lib/cyg/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
 m4_if([$1], [],[
       sys_lib_search_path_spec="$sys_lib_search_path_spec /usr/lib/w32api"])
       ;;
@@ -2559,14 +2579,14 @@
       ;;
     pw32*)
       # pw32 DLLs use 'pw' prefix rather than 'lib'
-      library_names_spec='`echo $libname | sed -e 's/^lib/pw/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
+      library_names_spec='`echo $libname | $SED -e 's/^lib/pw/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
       ;;
     esac
     dynamic_linker='Win32 ld.exe'
     ;;
 
-  *,cl*)
-    # Native MSVC
+  *,cl* | *,icl*)
+    # Native MSVC or ICC
     libname_spec='$name'
     soname_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
     library_names_spec='$libname.dll.lib'
@@ -2585,7 +2605,7 @@
       done
       IFS=$lt_save_ifs
       # Convert to MSYS style.
-      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | sed -e 's|\\\\|/|g' -e 's| \\([[a-zA-Z]]\\):| /\\1|g' -e 's|^ ||'`
+      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | $SED -e 's|\\\\|/|g' -e 's| \\([[a-zA-Z]]\\):| /\\1|g' -e 's|^ ||'`
       ;;
     cygwin*)
       # Convert to unix form, then to dos form, then back to unix form
@@ -2622,7 +2642,7 @@
     ;;
 
   *)
-    # Assume MSVC wrapper
+    # Assume MSVC and ICC wrapper
     library_names_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext $libname.lib'
     dynamic_linker='Win32 ld.exe'
     ;;
@@ -2655,7 +2675,7 @@
   shlibpath_var=LD_LIBRARY_PATH
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   # DragonFly does not have aout.  When/if they implement a new
   # versioning mechanism, adjust this.
   if test -x /usr/bin/objformat; then
@@ -3454,7 +3474,7 @@
 
 bsdi[[45]]*)
   lt_cv_deplibs_check_method='file_magic ELF [[0-9]][[0-9]]*-bit [[ML]]SB (shared object|dynamic lib)'
-  lt_cv_file_magic_cmd='/usr/bin/file -L'
+  lt_cv_file_magic_cmd='$FILECMD -L'
   lt_cv_file_magic_test_file=/shlib/libc.so
   ;;
 
@@ -3488,14 +3508,14 @@
   lt_cv_deplibs_check_method=pass_all
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   if echo __ELF__ | $CC -E - | $GREP __ELF__ > /dev/null; then
     case $host_cpu in
     i*86 )
       # Not sure whether the presence of OpenBSD here was a mistake.
       # Let's accept both of them until this is cleared up.
       lt_cv_deplibs_check_method='file_magic (FreeBSD|OpenBSD|DragonFly)/i[[3-9]]86 (compact )?demand paged shared library'
-      lt_cv_file_magic_cmd=/usr/bin/file
+      lt_cv_file_magic_cmd=$FILECMD
       lt_cv_file_magic_test_file=`echo /usr/lib/libc.so.*`
       ;;
     esac
@@ -3509,7 +3529,7 @@
   ;;
 
 hpux10.20* | hpux11*)
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   case $host_cpu in
   ia64*)
     lt_cv_deplibs_check_method='file_magic (s[[0-9]][[0-9]][[0-9]]|ELF-[[0-9]][[0-9]]) shared object file - IA64'
@@ -3556,7 +3576,7 @@
 
 newos6*)
   lt_cv_deplibs_check_method='file_magic ELF [[0-9]][[0-9]]*-bit [[ML]]SB (executable|dynamic lib)'
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   lt_cv_file_magic_test_file=/usr/lib/libnls.so
   ;;
 
@@ -3683,13 +3703,13 @@
 	mingw*) lt_bad_file=conftest.nm/nofile ;;
 	*) lt_bad_file=/dev/null ;;
 	esac
-	case `"$tmp_nm" -B $lt_bad_file 2>&1 | sed '1q'` in
+	case `"$tmp_nm" -B $lt_bad_file 2>&1 | $SED '1q'` in
 	*$lt_bad_file* | *'Invalid file or object type'*)
 	  lt_cv_path_NM="$tmp_nm -B"
 	  break 2
 	  ;;
 	*)
-	  case `"$tmp_nm" -p /dev/null 2>&1 | sed '1q'` in
+	  case `"$tmp_nm" -p /dev/null 2>&1 | $SED '1q'` in
 	  */dev/null*)
 	    lt_cv_path_NM="$tmp_nm -p"
 	    break 2
@@ -3715,7 +3735,7 @@
     # Let the user override the test.
   else
     AC_CHECK_TOOLS(DUMPBIN, [dumpbin "link -dump"], :)
-    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | sed '1q'` in
+    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | $SED '1q'` in
     *COFF*)
       DUMPBIN="$DUMPBIN -symbols -headers"
       ;;
@@ -3955,7 +3975,7 @@
 
 if test "$lt_cv_nm_interface" = "MS dumpbin"; then
   # Gets list of data symbols to import.
-  lt_cv_sys_global_symbol_to_import="sed -n -e 's/^I .* \(.*\)$/\1/p'"
+  lt_cv_sys_global_symbol_to_import="$SED -n -e 's/^I .* \(.*\)$/\1/p'"
   # Adjust the below global symbol transforms to fixup imported variables.
   lt_cdecl_hook=" -e 's/^I .* \(.*\)$/extern __declspec(dllimport) char \1;/p'"
   lt_c_name_hook=" -e 's/^I .* \(.*\)$/  {\"\1\", (void *) 0},/p'"
@@ -3973,20 +3993,20 @@
 # Transform an extracted symbol line into a proper C declaration.
 # Some systems (esp. on ia64) link data and code symbols differently,
 # so use this general approach.
-lt_cv_sys_global_symbol_to_cdecl="sed -n"\
+lt_cv_sys_global_symbol_to_cdecl="$SED -n"\
 $lt_cdecl_hook\
 " -e 's/^T .* \(.*\)$/extern int \1();/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/extern char \1;/p'"
 
 # Transform an extracted symbol line into symbol name and symbol address
-lt_cv_sys_global_symbol_to_c_name_address="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address="$SED -n"\
 $lt_c_name_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/  {\"\1\", (void *) \&\1},/p'"
 
 # Transform an extracted symbol line into symbol name with lib prefix and
 # symbol address.
-lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="$SED -n"\
 $lt_c_name_lib_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(lib.*\)$/  {\"\1\", (void *) \&\1},/p'"\
@@ -4010,7 +4030,7 @@
   if test "$lt_cv_nm_interface" = "MS dumpbin"; then
     # Fake it for dumpbin and say T for any non-static function,
     # D for any global variable and I for any imported variable.
-    # Also find C++ and __fastcall symbols from MSVC++,
+    # Also find C++ and __fastcall symbols from MSVC++ or ICC,
     # which start with @ or ?.
     lt_cv_sys_global_symbol_pipe="$AWK ['"\
 "     {last_section=section; section=\$ 3};"\
@@ -4028,9 +4048,9 @@
 "     s[1]~prfx {split(s[1],t,\"@\"); print f,t[1],substr(t[1],length(prfx))}"\
 "     ' prfx=^$ac_symprfx]"
   else
-    lt_cv_sys_global_symbol_pipe="sed -n -e 's/^.*[[	 ]]\($symcode$symcode*\)[[	 ]][[	 ]]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
+    lt_cv_sys_global_symbol_pipe="$SED -n -e 's/^.*[[	 ]]\($symcode$symcode*\)[[	 ]][[	 ]]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
   fi
-  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | sed '/ __gnu_lto/d'"
+  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | $SED '/ __gnu_lto/d'"
 
   # Check to see that the pipe works correctly.
   pipe_works=no
@@ -4317,7 +4337,7 @@
 	    ;;
 	esac
 	;;
-      freebsd* | dragonfly*)
+      freebsd* | dragonfly* | midnightbsd*)
 	# FreeBSD uses GNU C++
 	;;
       hpux9* | hpux10* | hpux11*)
@@ -4400,7 +4420,7 @@
 	    _LT_TAGVAR(lt_prog_compiler_static, $1)='-qstaticlink'
 	    ;;
 	  *)
-	    case `$CC -V 2>&1 | sed 5q` in
+	    case `$CC -V 2>&1 | $SED 5q` in
 	    *Sun\ C*)
 	      # Sun C++ 5.9
 	      _LT_TAGVAR(lt_prog_compiler_pic, $1)='-KPIC'
@@ -4736,7 +4756,7 @@
 	_LT_TAGVAR(lt_prog_compiler_static, $1)='-qstaticlink'
 	;;
       *)
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ Ceres\ Fortran* | *Sun*Fortran*\ [[1-7]].* | *Sun*Fortran*\ 8.[[0-3]]*)
 	  # Sun Fortran 8.3 passes all unrecognized flags to the linker
 	  _LT_TAGVAR(lt_prog_compiler_pic, $1)='-KPIC'
@@ -4919,7 +4939,7 @@
     if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
       _LT_TAGVAR(export_symbols_cmds, $1)='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && ([substr](\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
     else
-      _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+      _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
     fi
     ;;
   pw32*)
@@ -4927,7 +4947,7 @@
     ;;
   cygwin* | mingw* | cegcc*)
     case $cc_basename in
-    cl*)
+    cl* | icl*)
       _LT_TAGVAR(exclude_expsyms, $1)='_NULL_IMPORT_DESCRIPTOR|_IMPORT_DESCRIPTOR_.*'
       ;;
     *)
@@ -4984,15 +5004,15 @@
 
   case $host_os in
   cygwin* | mingw* | pw32* | cegcc*)
-    # FIXME: the MSVC++ port hasn't been tested in a loooong time
+    # FIXME: the MSVC++ and ICC port hasn't been tested in a loooong time
     # When not using gcc, we currently assume that we are using
-    # Microsoft Visual C++.
+    # Microsoft Visual C++ or Intel C++ Compiler.
     if test yes != "$GCC"; then
       with_gnu_ld=no
     fi
     ;;
   interix*)
-    # we just hope/assume this is gcc and not c89 (= MSVC++)
+    # we just hope/assume this is gcc and not c89 (= MSVC++ or ICC)
     with_gnu_ld=yes
     ;;
   openbsd* | bitrig*)
@@ -5044,7 +5064,7 @@
       _LT_TAGVAR(whole_archive_flag_spec, $1)=
     fi
     supports_anon_versioning=no
-    case `$LD -v | $SED -e 's/([^)]\+)\s\+//' 2>&1` in
+    case `$LD -v | $SED -e 's/([[^)]]\+)\s\+//' 2>&1` in
       *GNU\ gold*) supports_anon_versioning=yes ;;
       *\ [[01]].* | *\ 2.[[0-9]].* | *\ 2.10.*) ;; # catch versions < 2.11
       *\ 2.11.93.0.2\ *) supports_anon_versioning=yes ;; # RH7.3 ...
@@ -5156,6 +5176,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       _LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       _LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+      _LT_TAGVAR(file_list_spec, $1)='@'
       ;;
 
     interix[[3-9]]*)
@@ -5170,7 +5191,7 @@
       # 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
       # time.  Moving up from 0x10000000 also allows more sbrk(2) space.
       _LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-      _LT_TAGVAR(archive_expsym_cmds, $1)='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+      _LT_TAGVAR(archive_expsym_cmds, $1)='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
       ;;
 
     gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu)
@@ -5213,7 +5234,7 @@
 	  _LT_TAGVAR(compiler_needs_object, $1)=yes
 	  ;;
 	esac
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ C*)			# Sun C 5.9
 	  _LT_TAGVAR(whole_archive_flag_spec, $1)='$wl--whole-archive`new_convenience=; for conv in $convenience\"\"; do test -z \"$conv\" || new_convenience=\"$new_convenience,$conv\"; done; func_echo_all \"$new_convenience\"` $wl--no-whole-archive'
 	  _LT_TAGVAR(compiler_needs_object, $1)=yes
@@ -5225,7 +5246,7 @@
 
         if test yes = "$supports_anon_versioning"; then
           _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-            cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+            cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
             echo "local: *; };" >> $output_objdir/$libname.ver~
             $CC '"$tmp_sharedflag""$tmp_addflag"' $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
         fi
@@ -5241,7 +5262,7 @@
 	  _LT_TAGVAR(archive_cmds, $1)='$LD -shared $libobjs $deplibs $linker_flags -soname $soname -o $lib'
 	  if test yes = "$supports_anon_versioning"; then
 	    _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-              cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+              cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
               echo "local: *; };" >> $output_objdir/$libname.ver~
               $LD -shared $libobjs $deplibs $linker_flags -soname $soname -version-script $output_objdir/$libname.ver -o $lib'
 	  fi
@@ -5373,7 +5394,7 @@
 	if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
 	  _LT_TAGVAR(export_symbols_cmds, $1)='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && ([substr](\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
 	else
-	  _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+	  _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
 	fi
 	aix_use_runtimelinking=no
 
@@ -5556,12 +5577,12 @@
 
     cygwin* | mingw* | pw32* | cegcc*)
       # When not using gcc, we currently assume that we are using
-      # Microsoft Visual C++.
+      # Microsoft Visual C++ or Intel C++ Compiler.
       # hardcode_libdir_flag_spec is actually meaningless, as there is
       # no search path for DLLs.
       case $cc_basename in
-      cl*)
-	# Native MSVC
+      cl* | icl*)
+	# Native MSVC or ICC
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	_LT_TAGVAR(always_export_symbols, $1)=yes
@@ -5602,7 +5623,7 @@
           fi'
 	;;
       *)
-	# Assume MSVC wrapper
+	# Assume MSVC and ICC wrapper
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	# Tell ltmain to make .lib files, not .a files.
@@ -5650,7 +5671,7 @@
       ;;
 
     # FreeBSD 3 and greater uses gcc -shared to do shared libraries.
-    freebsd* | dragonfly*)
+    freebsd* | dragonfly* | midnightbsd*)
       _LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag -o $lib $libobjs $deplibs $compiler_flags'
       _LT_TAGVAR(hardcode_libdir_flag_spec, $1)='-R$libdir'
       _LT_TAGVAR(hardcode_direct, $1)=yes
@@ -5861,6 +5882,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       _LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       _LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+      _LT_TAGVAR(file_list_spec, $1)='@'
       ;;
 
     osf3*)
@@ -6631,8 +6653,8 @@
 
       cygwin* | mingw* | pw32* | cegcc*)
 	case $GXX,$cc_basename in
-	,cl* | no,cl*)
-	  # Native MSVC
+	,cl* | no,cl* | ,icl* | no,icl*)
+	  # Native MSVC or ICC
 	  # hardcode_libdir_flag_spec is actually meaningless, as there is
 	  # no search path for DLLs.
 	  _LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
@@ -6730,6 +6752,7 @@
 	  emximp -o $lib $output_objdir/$libname.def'
 	_LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
 	_LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+	_LT_TAGVAR(file_list_spec, $1)='@'
 	;;
 
       dgux*)
@@ -6760,7 +6783,7 @@
         _LT_TAGVAR(archive_cmds_need_lc, $1)=no
         ;;
 
-      freebsd* | dragonfly*)
+      freebsd* | dragonfly* | midnightbsd*)
         # FreeBSD 3 and later use GNU C++ and GNU ld with standard ELF
         # conventions
         _LT_TAGVAR(ld_shlibs, $1)=yes
@@ -6897,7 +6920,7 @@
 	# 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
 	# time.  Moving up from 0x10000000 also allows more sbrk(2) space.
 	_LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-	_LT_TAGVAR(archive_expsym_cmds, $1)='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+	_LT_TAGVAR(archive_expsym_cmds, $1)='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
 	;;
       irix5* | irix6*)
         case $cc_basename in
@@ -7037,13 +7060,13 @@
 	    _LT_TAGVAR(archive_cmds, $1)='$CC -qmkshrobj $libobjs $deplibs $compiler_flags $wl-soname $wl$soname -o $lib'
 	    if test yes = "$supports_anon_versioning"; then
 	      _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-                cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+                cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
                 echo "local: *; };" >> $output_objdir/$libname.ver~
                 $CC -qmkshrobj $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
 	    fi
 	    ;;
 	  *)
-	    case `$CC -V 2>&1 | sed 5q` in
+	    case `$CC -V 2>&1 | $SED 5q` in
 	    *Sun\ C*)
 	      # Sun C++ 5.9
 	      _LT_TAGVAR(no_undefined_flag, $1)=' -zdefs'
@@ -8189,6 +8212,14 @@
 AC_SUBST([DLLTOOL])
 ])
 
+# _LT_DECL_FILECMD
+# ----------------
+# Check for a file(cmd) program that can be used to detect file type and magic
+m4_defun([_LT_DECL_FILECMD],
+[AC_CHECK_TOOL([FILECMD], [file], [:])
+_LT_DECL([], [FILECMD], [1], [A file(cmd) program that detects file types])
+])# _LD_DECL_FILECMD
+
 # _LT_DECL_SED
 # ------------
 # Check for a fully-functional sed program, that truncates
diff --git a/scripts/ltoptions.m4 b/scripts/ltoptions.m4
index 94b0829..b0b5e9c 100644
--- a/scripts/ltoptions.m4
+++ b/scripts/ltoptions.m4
@@ -1,7 +1,7 @@
 # Helper functions for option handling.                    -*- Autoconf -*-
 #
-#   Copyright (C) 2004-2005, 2007-2009, 2011-2015 Free Software
-#   Foundation, Inc.
+#   Copyright (C) 2004-2005, 2007-2009, 2011-2019, 2021-2022 Free
+#   Software Foundation, Inc.
 #   Written by Gary V. Vaughan, 2004
 #
 # This file is free software; the Free Software Foundation gives
diff --git a/scripts/ltsugar.m4 b/scripts/ltsugar.m4
index 48bc934..902508b 100644
--- a/scripts/ltsugar.m4
+++ b/scripts/ltsugar.m4
@@ -1,6 +1,6 @@
 # ltsugar.m4 -- libtool m4 base layer.                         -*-Autoconf-*-
 #
-# Copyright (C) 2004-2005, 2007-2008, 2011-2015 Free Software
+# Copyright (C) 2004-2005, 2007-2008, 2011-2019, 2021-2022 Free Software
 # Foundation, Inc.
 # Written by Gary V. Vaughan, 2004
 #
diff --git a/scripts/ltversion.m4 b/scripts/ltversion.m4
index fa04b52..b155d0a 100644
--- a/scripts/ltversion.m4
+++ b/scripts/ltversion.m4
@@ -1,6 +1,7 @@
 # ltversion.m4 -- version numbers			-*- Autoconf -*-
 #
-#   Copyright (C) 2004, 2011-2015 Free Software Foundation, Inc.
+#   Copyright (C) 2004, 2011-2019, 2021-2022 Free Software Foundation,
+#   Inc.
 #   Written by Scott James Remnant, 2004
 #
 # This file is free software; the Free Software Foundation gives
@@ -9,15 +10,15 @@
 
 # @configure_input@
 
-# serial 4179 ltversion.m4
+# serial 4245 ltversion.m4
 # This file is part of GNU Libtool
 
-m4_define([LT_PACKAGE_VERSION], [2.4.6])
-m4_define([LT_PACKAGE_REVISION], [2.4.6])
+m4_define([LT_PACKAGE_VERSION], [2.4.7])
+m4_define([LT_PACKAGE_REVISION], [2.4.7])
 
 AC_DEFUN([LTVERSION_VERSION],
-[macro_version='2.4.6'
-macro_revision='2.4.6'
+[macro_version='2.4.7'
+macro_revision='2.4.7'
 _LT_DECL(, macro_version, 0, [Which release of libtool.m4 was used?])
 _LT_DECL(, macro_revision, 0)
 ])
diff --git a/scripts/lt~obsolete.m4 b/scripts/lt~obsolete.m4
index c6b26f8..0f7a875 100644
--- a/scripts/lt~obsolete.m4
+++ b/scripts/lt~obsolete.m4
@@ -1,7 +1,7 @@
 # lt~obsolete.m4 -- aclocal satisfying obsolete definitions.    -*-Autoconf-*-
 #
-#   Copyright (C) 2004-2005, 2007, 2009, 2011-2015 Free Software
-#   Foundation, Inc.
+#   Copyright (C) 2004-2005, 2007, 2009, 2011-2019, 2021-2022 Free
+#   Software Foundation, Inc.
 #   Written by Scott James Remnant, 2004.
 #
 # This file is free software; the Free Software Foundation gives
diff --git a/scripts/makefile.32sunu b/scripts/makefile.32sunu
index c849ecd..2993e0f 100644
--- a/scripts/makefile.32sunu
+++ b/scripts/makefile.32sunu
@@ -1,5 +1,6 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -21,9 +22,9 @@
 # Utilities:
 CC=cc
 AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -f -s
-RANLIB=echo
 RM_F=/bin/rm -f
 
 SUN_CC_FLAGS=-fast -xtarget=ultra
@@ -44,7 +45,7 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS=$(SUN_CC_FLAGS) # $(WARNMORE) -g
 LDFLAGS=$(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) libpng.a -lz -lm
@@ -69,9 +70,9 @@
 DL=$(DESTDIR)$(LIBPATH)
 DM=$(DESTDIR)$(MANPATH)
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -219,26 +220,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.64sunu b/scripts/makefile.64sunu
index 8880fa9..567c7e6 100644
--- a/scripts/makefile.64sunu
+++ b/scripts/makefile.64sunu
@@ -1,5 +1,6 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -21,9 +22,9 @@
 # Utilities:
 CC=cc
 AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -f -s
-RANLIB=echo
 RM_F=/bin/rm -f
 
 SUN_CC_FLAGS=-fast -xtarget=ultra -xarch=v9
@@ -44,7 +45,7 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS= $(SUN_CC_FLAGS) # $(WARNMORE) -g
 LDFLAGS=-L. -R. $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
@@ -69,9 +70,9 @@
 DL=$(DESTDIR)$(LIBPATH)
 DM=$(DESTDIR)$(MANPATH)
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -219,26 +220,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.aix b/scripts/makefile.aix
index 5f62d50..c5cc530 100644
--- a/scripts/makefile.aix
+++ b/scripts/makefile.aix
@@ -1,6 +1,6 @@
 # makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2000, 2022 Cosmin Truta
 # Copyright (C) 2002, 2006-2009, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000 Cosmin Truta
 # Copyright (C) 2000 Marc O. Gloor (AIX support added, from makefile.gcc)
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -16,8 +16,8 @@
 CC = gcc
 LD = $(CC)
 AR_RC = ar rcs
-MKDIR_P = mkdir -p
 RANLIB = ranlib
+MKDIR_P = mkdir -p
 RM_F = rm -f
 LN_SF = ln -f -s
 
@@ -43,13 +43,13 @@
 
 WARNMORE =
 CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng16 -lz -lm
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+LDFLAGS = -L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 .c.o:
diff --git a/scripts/makefile.amiga b/scripts/makefile.amiga
index 16a4bd5..2dae9af 100644
--- a/scripts/makefile.amiga
+++ b/scripts/makefile.amiga
@@ -33,9 +33,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 all: libpng.lib pngtest
 
diff --git a/scripts/makefile.atari b/scripts/makefile.atari
index b5dbd49..5b7baea 100644
--- a/scripts/makefile.atari
+++ b/scripts/makefile.atari
@@ -33,11 +33,11 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = $(LBR)(png.o) $(LBR)(pngset.o) $(LBR)(pngget.o) $(LBR)(pngrutil.o)\
-	$(LBR)(pngtrans.o) $(LBR)(pngwutil.o)\
-	$(LBR)(pngread.o) $(LBR)(pngerror.o) $(LBR)(pngwrite.o)\
-	$(LBR)(pngrtran.o) $(LBR)(pngwtran.o)\
-	$(LBR)(pngmem.o) $(LBR)(pngrio.o) $(LBR)(pngwio.o) $(LBR)(pngpread.o)
+OBJS = $(LBR)(png.o) $(LBR)(pngerror.o) $(LBR)(pngget.o) $(LBR)(pngmem.o) \
+       $(LBR)(pngpread.o) $(LBR)(pngread.o) $(LBR)(pngrio.o) \
+       $(LBR)(pngrtran.o) $(LBR)(pngrutil.o) $(LBR)(pngset.o) \
+       $(LBR)(pngtrans.o) $(LBR)(pngwio.o) $(LBR)(pngwrite.o) \
+       $(LBR)(pngwtran.o) $(LBR)(pngwutil.o)
 
 all: $(LBR) pngtest.ttp
 
diff --git a/scripts/makefile.bc32 b/scripts/makefile.bc32
index bdbc4cb..7e8f5e1 100644
--- a/scripts/makefile.bc32
+++ b/scripts/makefile.bc32
@@ -50,13 +50,13 @@
 # -M  generate map file
 LDFLAGS=-L$(ZLIB_DIR) -M $(LDEBUG)
 
-# Pre-built configuration
+## Pre-built configuration
 # See scripts\pnglibconf.mak for more options
 !ifndef PNGLIBCONF_H_PREBUILT
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
 !endif
 
-## Variables
+## File lists
 OBJS = \
 	png.obj \
 	pngerror.obj \
@@ -121,22 +121,22 @@
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
-png.obj: png.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.obj:      png.c      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.obj: pngerror.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.obj: pngget.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.obj: pngmem.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.obj:   pngget.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.obj:   pngmem.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.obj: pngpread.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.obj: pngread.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.obj: pngrio.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.obj:  pngread.c  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.obj:   pngrio.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.obj: pngrtran.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.obj: pngrutil.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.obj: pngset.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.obj:   pngset.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.obj: pngtrans.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.obj: pngwio.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.obj:   pngwio.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.obj: pngwrite.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.obj: pngwtran.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.obj: pngwutil.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtest.obj: pngtest.c png.h pngconf.h pnglibconf.h
+pngtest.obj:  pngtest.c  png.h pngconf.h pnglibconf.h
 
 $(LIBNAME): $(OBJS)
 	-del $(LIBNAME)
diff --git a/scripts/makefile.beos b/scripts/makefile.beos
index 01346f1..2ed049e 100644
--- a/scripts/makefile.beos
+++ b/scripts/makefile.beos
@@ -1,5 +1,6 @@
 # makefile for libpng on BeOS x86 ELF with gcc
 # modified from makefile.linux by Sander Stoks
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1999 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -21,9 +22,9 @@
 # Utilities:
 CC=gcc
 AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
@@ -37,14 +38,14 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 
 # On BeOS, -O1 is actually better than -O3.  This is a known bug but it's
 # still here in R4.5
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O1 -funroll-loops $(ALIGN) # $(WARNMORE) -g
+CFLAGS=-O1 -funroll-loops $(ALIGN) -Wall -Wextra -Wundef # $(WARNMORE) -g
 # LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz
-LDFLAGS=-L. -Wl,-soname=$(LIBSOMAJ) -L$(ZLIBLIB) -lz
+LDFLAGS=-L. -Wl,-soname=$(LIBSOMAJ) -L$(ZLIBLIB) -lz # -g
 
 # where make install puts libpng.a, libpng16.so*, and png.h
 prefix=/usr/local
@@ -73,9 +74,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS)
 
@@ -203,20 +204,20 @@
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.clang b/scripts/makefile.clang
index fcaefae..2e15423 100644
--- a/scripts/makefile.clang
+++ b/scripts/makefile.clang
@@ -1,6 +1,6 @@
 # makefile for libpng using clang (generic, static library)
+# Copyright (C) 2000, 2014, 2019-2022 Cosmin Truta
 # Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
@@ -19,12 +19,16 @@
 CP = cp
 RM_F = rm -f
 
+# Compiler and linker flags
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
 	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L$(ZLIBLIB)
+DEFS = $(NOHWOPT)
+CPPFLAGS = -I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+LDFLAGS = -L$(ZLIBLIB) # -g
 LIBS = -lz -lm
 
 # File extensions
@@ -34,10 +38,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static
diff --git a/scripts/makefile.darwin b/scripts/makefile.darwin
index 33c27cc..247343f 100644
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -1,4 +1,5 @@
-# makefile for libpng on Darwin / Mac OS X
+# makefile for libpng on Darwin / macOS
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2004, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 2001 Christoph Pfisterer
 # derived from makefile.linux:
@@ -11,6 +12,7 @@
 
 # where "make install" puts libpng.a, libpng16.dylib, png.h, pngconf.h,
 # and pnglibconf.h
+
 prefix=/usr/local
 exec_prefix=$(prefix)
 
@@ -21,6 +23,7 @@
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
+RELEASE = 38
 
 # Shared library names:
 LIBSO=$(LIBNAME).dylib
@@ -31,15 +34,17 @@
 # Utilities:
 CC=cc
 AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 CP=cp
-RM_F=/bin/rm -f
+RM_F=rm -f
 
-CPPFLAGS=-I$(ZLIBINC)
-# CFLAGS=-W -Wall -O3 -funroll-loops
-CFLAGS=-W -Wall -O -funroll-loops
+NOHWOPT=-DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+        -DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
+DEFS=$(NOHWOPT)
+CPPFLAGS=-I$(ZLIBINC) $(DEFS)
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz
 
 INCPATH=$(prefix)/include
@@ -66,9 +71,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -200,26 +206,22 @@
 	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
 	libpng.pc $(LIBNAME).*dylib pngtesti pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.dec b/scripts/makefile.dec
index 8566a02..80a9cb3 100644
--- a/scripts/makefile.dec
+++ b/scripts/makefile.dec
@@ -17,11 +17,11 @@
 OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
+AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir
 LN_SF=ln -f -s
-RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
@@ -62,9 +62,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -75,7 +75,7 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR_RC) $@ $(OBJS)
 	$(RANLIB) $@
 
 libpng.pc:
@@ -191,20 +191,20 @@
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.dj2 b/scripts/makefile.dj2
index e59c432..3d493e6 100644
--- a/scripts/makefile.dj2
+++ b/scripts/makefile.dj2
@@ -1,4 +1,5 @@
 # DJGPP (DOS gcc) makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2009-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -17,8 +18,6 @@
 CFLAGS=-O
 LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
 
-RANLIB=ranlib
-
 CP=cp
 RM_F=rm -f
 
@@ -26,9 +25,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o pngwtran.o \
-	pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -39,8 +38,8 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	ar rc $@  $(OBJS)
-	$(RANLIB) $@
+	ar rc $@ $(OBJS)
+	ranlib $@
 
 pngtest: pngtest.o libpng.a
 	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
@@ -53,14 +52,14 @@
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
@@ -69,4 +68,4 @@
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.clang-asan b/scripts/makefile.emcc
similarity index 67%
rename from scripts/makefile.clang-asan
rename to scripts/makefile.emcc
index 0cab52f..5d27621 100644
--- a/scripts/makefile.clang-asan
+++ b/scripts/makefile.emcc
@@ -1,6 +1,7 @@
-# makefile for libpng using clang + address sanitizer (generic, static library)
+# makefile for libpng using emscripten
+# Copyright (C) 2000, 2014, 2019-2022 Cosmin Truta
+# Copyright (C) 2021 Kirk Roerig
 # Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
@@ -12,32 +13,27 @@
 ZLIBLIB = ../zlib
 
 # Compiler, linker, lib and other tools
-CC = clang
+CC = emcc
 LD = $(CC)
-AR_RC = ar rcs
-RANLIB = ranlib
+AR_RC = emar rcs
+RANLIB = emranlib
 CP = cp
 RM_F = rm -f
 
-WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O0 -g -fsanitize=address
-LDFLAGS = -L$(ZLIBLIB) -g -fsanitize=address
+CFLAGS = -O2 -Wall -Wextra -Wundef
+LDFLAGS = -L$(ZLIBLIB)
+PNGTEST_LDFLAGS = --preload-file=pngtest.png
 LIBS = -lz -lm
 
-# File extensions
-EXEEXT =
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static
@@ -48,25 +44,25 @@
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-static: libpng.a pngtest$(EXEEXT)
+static: libpng.a pngtest
 
 shared:
-	@echo This is a generic makefile that cannot create shared libraries.
-	@echo Please use a configuration that is specific to your platform.
+	@echo This makefile cannot create shared libraries.
 	@false
 
 libpng.a: $(OBJS)
 	$(AR_RC) $@ $(OBJS)
 	$(RANLIB) $@
 
-test: pngtest$(EXEEXT)
-	./pngtest$(EXEEXT)
+test: pngtest
+	node ./pngtest
 
-pngtest$(EXEEXT): pngtest.o libpng.a
-	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
+pngtest: pngtest.o libpng.a
+	$(LD) $(LDFLAGS) $(PNGTEST_LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 clean:
-	$(RM_F) *.o libpng.a pngtest$(EXEEXT) pngout.png pnglibconf.h
+	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
+	$(RM_F) pngtest.data pngtest.wasm
 
 png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
diff --git a/scripts/makefile.freebsd b/scripts/makefile.freebsd
index 5fec61e..cdd3994 100644
--- a/scripts/makefile.freebsd
+++ b/scripts/makefile.freebsd
@@ -1,4 +1,5 @@
 # makefile for libpng under FreeBSD
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2014 Glenn Randers-Pehrson and Andrey A. Chernov
 # Copyright (C) 2002, 2007, 2009 Glenn Randers-Pehrson and Andrey A. Chernov
 #
@@ -37,15 +38,15 @@
 DPADD+=		${LIBM} ${LIBZ}
 
 CPPFLAGS+=	-I. -I${ZLIBINC}
-CFLAGS+=	-W -Wall
+CFLAGS+=	-Wall -Wextra -Wundef
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT= scripts/pnglibconf.h.prebuilt
 
-SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
-	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
-	pngwtran.c pngmem.c pngerror.c pngpread.c
+SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -62,8 +63,4 @@
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	cp $(PNGLIBCONF_H_PREBUILT) $@
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 .include <bsd.lib.mk>
diff --git a/scripts/makefile.gcc b/scripts/makefile.gcc
index a977313..b215a70 100644
--- a/scripts/makefile.gcc
+++ b/scripts/makefile.gcc
@@ -1,6 +1,6 @@
 # makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2000, 2014, 2019-2022 Cosmin Truta
 # Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
@@ -19,12 +19,16 @@
 CP = cp
 RM_F = rm -f
 
+# Compiler and linker flags
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
 	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L$(ZLIBLIB)
+DEFS = $(NOHWOPT)
+CPPFLAGS = -I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+LDFLAGS = -L$(ZLIBLIB) # -g
 LIBS = -lz -lm
 
 # File extensions
@@ -34,10 +38,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static
diff --git a/scripts/makefile.gcc-asan b/scripts/makefile.gcc-asan
deleted file mode 100644
index aae55d6..0000000
--- a/scripts/makefile.gcc-asan
+++ /dev/null
@@ -1,87 +0,0 @@
-# makefile for libpng using gcc + address sanitizer (generic, static library)
-# Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
-# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# Location of the zlib library and include files
-ZLIBINC = ../zlib
-ZLIBLIB = ../zlib
-
-# Compiler, linker, lib and other tools
-CC = gcc
-LD = $(CC)
-AR_RC = ar rcs
-RANLIB = ranlib
-CP = cp
-RM_F = rm -f
-
-WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O0 -g -fsanitize=address
-LDFLAGS = -L$(ZLIBLIB) -g -fsanitize=address
-LIBS = -lz -lm
-
-# File extensions
-EXEEXT =
-
-# Pre-built configuration
-# See scripts/pnglibconf.mak for more options
-PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
-
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
-
-# Targets
-all: static
-
-pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
-	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
-
-.c.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
-
-static: libpng.a pngtest$(EXEEXT)
-
-shared:
-	@echo This is a generic makefile that cannot create shared libraries.
-	@echo Please use a configuration that is specific to your platform.
-	@false
-
-libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
-	$(RANLIB) $@
-
-test: pngtest$(EXEEXT)
-	./pngtest$(EXEEXT)
-
-pngtest$(EXEEXT): pngtest.o libpng.a
-	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
-
-clean:
-	$(RM_F) *.o libpng.a pngtest$(EXEEXT) pngout.png pnglibconf.h
-
-png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-
-pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.hp64 b/scripts/makefile.hp64
index 4421e78..c05b141 100644
--- a/scripts/makefile.hp64
+++ b/scripts/makefile.hp64
@@ -1,4 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 1999-2002, 2006, 2009, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # Contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
@@ -29,11 +30,11 @@
 OLDSO=libpng.sl
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
+AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
@@ -72,9 +73,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -206,26 +207,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.hpgcc b/scripts/makefile.hpgcc
index efef1f3..84bdb54 100644
--- a/scripts/makefile.hpgcc
+++ b/scripts/makefile.hpgcc
@@ -1,4 +1,5 @@
 # makefile for libpng on HP-UX using GCC with the HP ANSI/C linker.
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006-2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 2001, Laurent faillie
 # Copyright (C) 1998, 1999 Greg Roelofs
@@ -22,9 +23,9 @@
 CC=gcc
 LD=ld
 AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
@@ -44,20 +45,14 @@
 #   LDSHARED=ld -b
 #   SHAREDLIB=libz.sl
 
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O3 -funroll-loops $(ALIGN) # $(WARNMORE) -g
-#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef # $(WARNMORE) -g
+#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -79,9 +74,9 @@
 DL=$(DESTDIR)$(LIBPATH)
 DM=$(DESTDIR)$(MANPATH)
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -209,26 +204,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.hpux b/scripts/makefile.hpux
index 27b312a..58b0f9d 100644
--- a/scripts/makefile.hpux
+++ b/scripts/makefile.hpux
@@ -1,4 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 1999-2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # Contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
@@ -30,11 +31,11 @@
 OLDSO=libpng.sl
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
+AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 RM_F=/bin/rm -f
 
 # where make install puts libpng.a, libpng16.sl, and png.h
@@ -70,9 +71,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -204,26 +205,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.ibmc b/scripts/makefile.ibmc
index 89b1196..95cd0d8 100644
--- a/scripts/makefile.ibmc
+++ b/scripts/makefile.ibmc
@@ -1,7 +1,7 @@
 # Makefile for libpng (static)
 # IBM C version 3.x for Win32 and OS/2
 # Copyright (C) 2006, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000 Cosmin Truta
+# Copyright (C) 2000, 2020 Cosmin Truta
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -37,10 +37,10 @@
 A=.lib
 E=.exe
 
-# Variables
+# File lists
 OBJS = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O) \
-	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
-	pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+       pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
+       pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
 
 LIBS = libpng$(A) $(ZLIBLIB)/zlib$(A)
 
@@ -65,11 +65,11 @@
 	$(LD) $(LDFLAGS) pngtest$(O) $(LIBS)
 
 clean:
-	$(RM) *$(O)
-	$(RM) libpng$(A)
-	$(RM) pnglibconf.h
-	$(RM) pngtest$(E)
-	$(RM) pngout.png
+	-$(RM) *$(O)
+	-$(RM) libpng$(A)
+	-$(RM) pnglibconf.h
+	-$(RM) pngtest$(E)
+	-$(RM) pngout.png
 
 png$(O):      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
diff --git a/scripts/makefile.intel b/scripts/makefile.intel
index 4187261..d996011 100644
--- a/scripts/makefile.intel
+++ b/scripts/makefile.intel
@@ -31,7 +31,7 @@
 
 # --------------------------------------------------------------------------
 
-CC=icl -c
+CC=icl
 CPPFLAGS=-I$(ZLIBINC)
 CFLAGS=-O2 -G$(CPU)$(CALLING) -Qip -Qunroll4 -nologo
 LD=link
@@ -42,61 +42,65 @@
 # See scripts\pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
 
+# File extensions
 O=.obj
 
-OBJS=png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O) \
-pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O) \
-pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+# File lists
+OBJS1=png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2=pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3=pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS=$(OBJS1) $(OBJS2) $(OBJS3)
 
+# Targets
 all: test
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 libpng.lib: $(OBJS)
 	if exist libpng.lib del libpng.lib
@@ -106,10 +110,9 @@
 	$(LD) $(LDFLAGS) /OUT:pngtest.exe pngtest.obj libpng.lib $(ZLIBLIB)\zlib.lib
 
 pngtest$(O): png.h pngconf.h pnglibconf.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 test: pngtest.exe
 	pngtest.exe
 
-
 # End of makefile for libpng
diff --git a/scripts/makefile.linux b/scripts/makefile.linux
index f2d8bea..1d8c663 100644
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so on Linux ELF with gcc
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010-2014 Greg Roelofs and
 # Glenn Randers-Pehrson
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -10,7 +11,7 @@
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 37
+RELEASE = 38
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
@@ -19,13 +20,13 @@
 OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
+AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=ranlib
 CP=cp
-RM_F=/bin/rm -f
+RM_F=rm -f
 
 # where "make install" puts libpng16.a, libpng16.so*,
 # libpng16/png.h, libpng16/pngconf.h, and libpng16/pnglibconf.h
@@ -39,21 +40,17 @@
 ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
+# Compiler and linker flags
+NOHWOPT=-DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
-
-CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O3 -funroll-loops $(ALIGN) # $(WARNMORE) -g
-
-LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
+DEFS=$(NOHWOPT)
+CPPFLAGS=-I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef # $(WARNMORE) -g
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm # -g
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -79,9 +76,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -167,7 +165,6 @@
 	(cd $(DL); \
 	$(LN_SF) $(LIBSOREL) $(LIBSO); \
 	$(LN_SF) $(LIBSO) $(OLDSO))
-
 	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
 	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
 	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
@@ -210,6 +207,8 @@
 	./pngtestd pngtest.png
 
 test-installed:
+	echo
+	echo Testing installed dynamic shared library.
 	$(CC) $(CPPFLAGS) \
 	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
 	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
@@ -217,30 +216,27 @@
 	./pngtesti pngtest.png
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) $(OBJS) $(OBJSDLL) libpng.a
+	$(RM_F) pngtest*.o pngtest pngtesti pngtest-static pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)*
+	$(RM_F) libpng.pc pnglibconf.h libpng-config
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.linux-opt b/scripts/makefile.linux-opt
deleted file mode 100644
index 327151f..0000000
--- a/scripts/makefile.linux-opt
+++ /dev/null
@@ -1,265 +0,0 @@
-# makefile for libpng.a and libpng16.so on Linux ELF with gcc
-# Copyright (C) 1998,1999,2002,2006,2008,2010-2014,2017 Greg Roelofs and
-# Glenn Randers-Pehrson
-# Copyright (C) 1996,1997 Andreas Dilger
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
-RELEASE = 37
-
-# Shared library names:
-LIBSO=$(LIBNAME).so
-LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
-
-# Utilities:
-AR_RC=ar rc
-CC=gcc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
-RANLIB=ranlib
-CP=cp
-RM_F=/bin/rm -f
-
-# where "make install" puts libpng16.a, libpng16.so*,
-# libpng16/png.h, libpng16/pngconf.h, and libpng16/pnglibconf.h
-# Prefix must be a full pathname.
-prefix=/usr/local
-exec_prefix=$(prefix)
-
-# Where the zlib library and include files are located.
-#ZLIBLIB=/usr/local/lib
-#ZLIBINC=/usr/local/include
-ZLIBLIB=../zlib
-ZLIBINC=../zlib
-
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
-#WARNMORE=-Wwrite-strings -Wpointer-arith \
-#	-Wmissing-declarations -Wtraditional -Wcast-align \
-#	-Wstrict-prototypes -Wmissing-prototypes
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
-
-CPPFLAGS=-I$(ZLIBINC)
-CPPFLAGS += -DPNG_ARM_NEON
-CPPFLAGS += -DPNG_MIPS_MSA
-CPPFLAGS += -DPNG_INTEL_SSE
-CPPFLAGS += -DPNG_POWERPC_VSX
-CPPFLAGS+=-ansi -pedantic -Wextra -Wall -Wshadow -Wno-sign-conversion
-CPPFLAGS+=-W -Wall -Wconversion $(ALIGN)
-# CPPFLAGS+=$(WARNMORE)
-CFLAGS= -O3 -funroll-loops
-
-LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
-
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
-# Pre-built configuration
-# See scripts/pnglibconf.mak for more options
-PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
-
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o \
-	arm/arm_init.o arm/filter_neon_intrinsics.o \
-	mips/mips_init.o mips/filter_msa_intrinsics.o \
-	intel/intel_init.o intel/filter_sse2_intrinsics.o\
-	powerpc/powerpc_init.o powerpc/filter_vsx_intrinsics.o
-
-OBJSDLL = $(OBJS:.o=.pic.o)
-
-.SUFFIXES:      .c .o .pic.o
-
-.c.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
-
-.c.pic.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fPIC -o $@ $*.c
-
-all: libpng.a $(LIBSO) pngtest pngtest-static libpng.pc libpng-config
-
-pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
-	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
-
-libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
-	$(RANLIB) $@
-
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
-$(LIBSO): $(LIBSOMAJ)
-	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
-
-$(LIBSOMAJ): $(OBJSDLL)
-	$(CC) -shared -Wl,-soname,$(LIBSOMAJ) -o $(LIBSOMAJ) $(OBJSDLL)
-
-pngtest: pngtest.o $(LIBSO)
-	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
-
-pngtest-static: pngtest.o libpng.a
-	$(CC) -o pngtest-static $(CFLAGS) pngtest.o $(LDFLAGS_A)
-
-test: pngtest pngtest-static
-	@echo ""
-	@echo "   Running pngtest dynamically linked with $(LIBSO):"
-	@echo ""
-	./pngtest
-	@echo ""
-	@echo "   Running pngtest statically linked with libpng.a:"
-	@echo ""
-	./pngtest-static
-
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
-
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
-
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) -Wl, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
-
-clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
-# DO NOT DELETE THIS LINE -- make depend depends on it.
-
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-arm/arm_init.o arm/arm_init.o: pngpriv.h
-arm/filter_neon_intrinsics.o arm/filter_neon_intrinsics.pic.o: pngpriv.h
-mips/mips_init.o mips/mips_init.pic.o: pngpriv.h
-mips/filter_msa_intrinsics.o mips/filter_msa_intrinsics.pic.:  pngpriv.h
-intel/intel_init.o intel/intel_init.pic.:  pngpriv.h
-intel/filter_sse2_intrinsics.o intel/filter_sse2_intrinsics.pic.:  pngpriv.h
-powerpc/powerpc_init.o powerpc/powerpc_init.pic.:  pngpriv.h
-powerpc/filter_vsx_intrinsics.o powerpc/filter_vsx_intrinsics.pic.:  pngpriv.h
-
-pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.mips b/scripts/makefile.mips
index 0357ae8..c96eb61 100644
--- a/scripts/makefile.mips
+++ b/scripts/makefile.mips
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 1998-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -36,9 +37,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -49,7 +50,7 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	ar rc $@  $(OBJS)
+	ar rc $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
@@ -78,26 +79,22 @@
 clean:
 	rm -f *.o libpng.a pngtest pngout.png pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.msys b/scripts/makefile.msys
index 6b9daf8..d5fadc1 100644
--- a/scripts/makefile.msys
+++ b/scripts/makefile.msys
@@ -1,5 +1,5 @@
 # makefile for libpng using MSYS/gcc (shared, static library)
-# Copyright (C) 2019 Cosmin Truta
+# Copyright (C) 2019-2022 Cosmin Truta
 # Copyright (C) 2012 Glenn Randers-Pehrson and Christopher M. Wheeler
 #
 # Portions taken from makefile.linux and makefile.gcc:
@@ -19,7 +19,7 @@
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 37
+RELEASE = 38
 
 # Shared library names:
 LIBSO=$(LIBNAME).dll
@@ -43,12 +43,9 @@
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
 
-#ARCH = -march=pentium3
-#ARCH = -march=i686
-ARCH =
 CPPFLAGS = # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 $(ARCH) # -g
-LDFLAGS =
+CFLAGS = -O2 -Wall -Wextra -Wundef # -g
+LDFLAGS = # -g
 LIBS = -lz -lm
 
 # File extensions
@@ -67,7 +64,6 @@
 # If you're going to install into a temporary location
 # via DESTDIR, $(DESTDIR)$(prefix) must already exist before
 # you execute make install.
-
 DESTDIR=
 
 DB=$(DESTDIR)$(BINPATH)
@@ -79,10 +75,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static shared
@@ -146,7 +142,6 @@
 	(cd $(DL); \
 	$(LN_SF) $(LIBSOREL) $(LIBSO); \
 	$(LN_SF) $(LIBSO) $(OLDSO))
-
 	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
 	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
 	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
@@ -180,8 +175,10 @@
 	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 clean:
-	$(RM_F) *.o libpng.a pngtest$(EXEEXT) pngout.png pnglibconf.h $(LIBSO) \
-	$(LIBSOMAJ) libpng-config
+	$(RM_F) $(OBJS) libpng.a
+	$(RM_F) pngtest*.o pngtest$(EXEEXT) pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)
+	$(RM_F) libpng.pc pnglibconf.h libpng-config
 
 png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
diff --git a/scripts/makefile.netbsd b/scripts/makefile.netbsd
index 9a6b046..48cac07 100644
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -14,12 +14,12 @@
 INCSDIR=${LOCALBASE}/include
 
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.37
+SHLIB_MINOR=	1.6.38
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
-	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c pngtrans.c \
-	pngwio.c pngwrite.c pngwtran.c pngwutil.c
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 INCS=	png.h pngconf.h pnglibconf.h
 MAN=	libpng.3 libpngpf.3 png.5
 
diff --git a/scripts/makefile.openbsd b/scripts/makefile.openbsd
index ad5ffb3..97d11b8 100644
--- a/scripts/makefile.openbsd
+++ b/scripts/makefile.openbsd
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2007-2009, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -11,18 +12,18 @@
 MANDIR= ${PREFIX}/man/cat
 
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.37
+SHLIB_MINOR=	1.6.38
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
-	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c pngtrans.c \
-	pngwio.c pngwrite.c pngwtran.c pngwutil.c
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 HDRS=	png.h pngconf.h pnglibconf.h
 MAN=	libpng.3 libpngpf.3 png.5
 DOCS=	ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO \
 	libpng-manual.txt
 
-CFLAGS+= -W -Wall
+CFLAGS+= -Wall -Wextra -Wundef
 CPPFLAGS+= -I${.CURDIR}
 
 NOPROFILE= Yes
diff --git a/scripts/makefile.sco b/scripts/makefile.sco
index 01d7eaa..67cc8e7 100644
--- a/scripts/makefile.sco
+++ b/scripts/makefile.sco
@@ -1,6 +1,7 @@
 # makefile for SCO OSr5  ELF and Unixware 7 with Native cc
 # Contributed by Mike Hopkirk (hops at sco.com) modified from Makefile.lnx
 #   force ELF build dynamic linking, SONAME setting in lib and RPATH in app
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -22,9 +23,9 @@
 # Utilities:
 CC=cc
 AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir
 LN_SF=ln -f -s
-RANLIB=echo
 CP=cp
 RM_F=/bin/rm -f
 
@@ -66,9 +67,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -201,26 +202,22 @@
 	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
 	pnglibconf.h libpng.pc
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sggcc b/scripts/makefile.sggcc
index 82efe7a..37f7d2d 100644
--- a/scripts/makefile.sggcc
+++ b/scripts/makefile.sggcc
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so, SGI IRIX with 'cc'
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2001-2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -17,11 +18,11 @@
 OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
+AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=echo
 CP=cp
 RM_F=/bin/rm -f
 
@@ -46,7 +47,7 @@
 WARNMORE=
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS=$(ABI) -O $(WARNMORE) -fPIC -mabi=n32 # -g
-LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm # -g
 LDSHARED=cc $(ABI) -shared -soname $(LIBSOMAJ) \
 	-set_version sgi$(PNGMAJ).0
 # See "man dso" for info about shared objects
@@ -76,9 +77,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -211,26 +212,22 @@
 	$(RM_F) libpng.a pngtest pngtesti pngout.png libpng.pc \
 	so_locations libpng-config $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sgi b/scripts/makefile.sgi
index 5d9c23f..1ead8d8 100644
--- a/scripts/makefile.sgi
+++ b/scripts/makefile.sgi
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so, SGI IRIX with 'cc'
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2001-2002, 2006, 2007, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -17,11 +18,11 @@
 OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
+AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -sf
-RANLIB=echo
 CP=cp
 RM_F=/bin/rm -f
 
@@ -47,9 +48,9 @@
 # Note: -KPIC is the default anyhow
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 #CFLAGS= $(ABI) -O $(WARNMORE) -KPIC # -g
-CFLAGS=$(ABI) -O $(WARNMORE)
-LDFLAGS_A=$(ABI) -L. -L$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+CFLAGS=$(ABI) -O $(WARNMORE) # -g
+LDFLAGS_A=$(ABI) -L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm # -g
 LDSHARED=cc $(ABI) -shared -soname $(LIBSOMAJ) \
 	-set_version sgi$(PNGMAJ).0
 # See "man dso" for info about shared objects
@@ -79,9 +80,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -212,26 +213,22 @@
 	$(LIBSO) $(LIBSOMAJ)* \
 	so_locations pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.so9 b/scripts/makefile.so9
index 93166f3..865c060 100644
--- a/scripts/makefile.so9
+++ b/scripts/makefile.so9
@@ -1,6 +1,7 @@
 # makefile for libpng on Solaris 9 (beta) with Forte cc
 # Updated by Chad Schrock for Solaris 9
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998-2001 Greg Roelofs
 # Copyright (C) 1996-1997 Andreas Dilger
@@ -23,9 +24,9 @@
 # gcc 2.95 doesn't work.
 CC=cc
 AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -f -s
-RANLIB=echo
 CP=cp
 RM_F=/bin/rm -f
 
@@ -44,11 +45,7 @@
 ZLIBLIB=/usr/lib
 ZLIBINC=/usr/include
 
-#WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-#CFLAGS=-W -Wall -O3 $(WARNMORE) -g
 CFLAGS=-O3
 LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
 
@@ -76,9 +73,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -222,26 +219,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.solaris b/scripts/makefile.solaris
index f6d7b58..180bdd0 100644
--- a/scripts/makefile.solaris
+++ b/scripts/makefile.solaris
@@ -1,4 +1,5 @@
 # makefile for libpng on Solaris 2.x with gcc
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2004, 2006-2008, 2010-2014 Glenn Randers-Pehrson
 # Contributed by William L. Sebok, based on makefile.linux
 # Copyright (C) 1998 Greg Roelofs
@@ -19,11 +20,11 @@
 OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
+AR_RC=ar rc
+RANLIB=echo
 MKDIR_P=mkdir -p
 LN_SF=ln -f -s
-RANLIB=echo
 CP=cp
 RM_F=/bin/rm -f
 
@@ -42,10 +43,10 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O # $(WARNMORE) -g
-LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
+CFLAGS=-O -Wall -Wextra -Wundef # $(WARNMORE) -g
+LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm # -g
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -71,9 +72,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -218,26 +219,22 @@
 	libpng-config $(LIBSO) $(LIBSOMAJ)* \
 	libpng.pc pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.std b/scripts/makefile.std
index 2f4871d..ed1105f 100644
--- a/scripts/makefile.std
+++ b/scripts/makefile.std
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -28,30 +29,33 @@
 ZLIBINC=../zlib
 
 CC = cc
+CPP = $(CC) -E
+LD = $(CC)
 AR_RC = ar rc
+RANLIB = ranlib
 MKDIR_P = mkdir
 LN_SF = ln -sf
-RANLIB = ranlib
 CP = cp
+MV_F = mv -f
 RM_F = rm -f
 AWK = awk
-SED = sed
-CPP = $(CC) -E
-ECHO = echo
 
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 DFNFLAGS = # DFNFLAGS contains -D options to use in the libpng build
 DFA_EXTRA = # extra files that can be used to control configuration
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
+CPPFLAGS = -I$(ZLIBINC) $(NOHWOPT) # -DPNG_DEBUG=5
 CFLAGS = -O # -g
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng -lz -lm
+LDFLAGS = -L$(ZLIBLIB) # -g
+LIBS = -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -62,28 +66,28 @@
 # copy this if the following doesn't work.
 pnglibconf.h: pnglibconf.dfn
 	$(RM_F) $@ pnglibconf.c pnglibconf.out pnglibconf.tmp
-	$(ECHO) '#include "pnglibconf.dfn"' >pnglibconf.c
-	$(ECHO) "If '$(CC) -E' crashes try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
+	echo '#include "pnglibconf.dfn"' >pnglibconf.c
+	@echo "## If '$(CC) -E' fails, try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
 	$(CPP) $(DFNFLAGS) pnglibconf.c >pnglibconf.out
-	$(AWK) -f "scripts/dfn.awk" out="pnglibconf.tmp" pnglibconf.out 1>&2
-	mv pnglibconf.tmp $@
+	$(AWK) -f scripts/dfn.awk out=pnglibconf.tmp pnglibconf.out >&2
+	$(MV_F) pnglibconf.tmp $@
 
 pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
 	$(RM_F) $@ pnglibconf.pre pnglibconf.tmp
-	$(ECHO) "Calling $(AWK) from scripts/pnglibconf.mak" >&2
-	$(ECHO) "If 'awk' crashes try a better awk (e.g. AWK='nawk')" >&2
-	$(AWK) -f scripts/options.awk out="pnglibconf.pre"\
+	@echo "## Calling $(AWK) from scripts/pnglibconf.mak" >&2
+	@echo "## If 'awk' fails, try a better awk (e.g. AWK='nawk')" >&2
+	$(AWK) -f scripts/options.awk out=pnglibconf.pre\
 	    version=search pngconf.h scripts/pnglibconf.dfa\
-	    pngusr.dfa $(DFA_XTRA) 1>&2
-	$(AWK) -f scripts/options.awk out="pnglibconf.tmp" pnglibconf.pre 1>&2
-	mv pnglibconf.tmp $@
+	    pngusr.dfa $(DFA_XTRA) >&2
+	$(AWK) -f scripts/options.awk out=pnglibconf.tmp pnglibconf.pre >&2
+	$(MV_F) pnglibconf.tmp $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR_RC) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 test: pngtest
 	./pngtest
@@ -106,29 +110,25 @@
 	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h pnglibconf.c \
-	pnglibconf.out
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
+	$(RM_F) pnglibconf.c pnglibconf.dfn pnglibconf.out pnglibconf.pre
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sunos b/scripts/makefile.sunos
index 9a0e28e..13450ec 100644
--- a/scripts/makefile.sunos
+++ b/scripts/makefile.sunos
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2002, 2006, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -27,30 +28,25 @@
 ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
-
-WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow -Wconversion \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes
-
 CC=gcc
 AR_RC=ar rc
+RANLIB=ranlib
 MKDIR_P=mkdir -p
 LN_SF=ln -f -s
-RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-O # $(WARNMORE)
+CFLAGS=-O
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -61,7 +57,7 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR_RC) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
@@ -90,26 +86,22 @@
 clean:
 	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.vcwin-arm64 b/scripts/makefile.vcwin-arm64
new file mode 100644
index 0000000..9795ba6
--- /dev/null
+++ b/scripts/makefile.vcwin-arm64
@@ -0,0 +1,123 @@
+# makefile for libpng on win-arm64
+# Copyright (C) 2021 Gabor Kertesz
+# Copyright (C) 1998 Tim Wegner
+# Copyright (C) 2006,2009,2011,2014 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+#
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+# To use, do "nmake /f scripts\makefile.vcwin-arm64"
+
+# -------- Microsoft Visual C++ 2.0 and later --------
+
+# Compiler, linker, librarian and other tools
+CC = cl
+LD = link
+AR = lib
+CPPFLAGS = -I..\zlib
+CFLAGS  = -nologo -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -DPNG_ARM_NEON_OPT=1 -MD -O2 -W3
+LDFLAGS = -nologo
+ARFLAGS = -nologo
+CP = copy
+RM = del
+
+# Uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
+# Pre-built configuration
+# See scripts\pnglibconf.mak for more options
+PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
+
+# File extensions
+O=.obj
+
+# File lists
+OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS4 = arm_init$(O) filter_neon_intrinsics$(O) palette_neon_intrinsics$(O)
+OBJS  = $(OBJS1) $(OBJS2) $(OBJS3) $(OBJS4)
+
+# Targets
+all: libpng.lib
+
+pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
+	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
+
+png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+arm_init$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+filter_neon_intrinsics$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+palette_neon_intrinsics$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+libpng.lib: $(OBJS)
+	-$(RM) $@
+	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
+
+pngtest.exe: pngtest$(O) libpng.lib
+	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h pnglibconf.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+test: pngtest.exe
+	pngtest.exe
+
+clean:
+	-$(RM) *$(O)
+	-$(RM) libpng.lib
+	-$(RM) pnglibconf.h
+	-$(RM) pngtest.exe
+	-$(RM) pngout.png
+
+# End of makefile for libpng
diff --git a/scripts/makefile.vcwin32 b/scripts/makefile.vcwin32
index 2bd143c..ebc053d 100644
--- a/scripts/makefile.vcwin32
+++ b/scripts/makefile.vcwin32
@@ -22,6 +22,9 @@
 CP = copy
 RM = del
 
+# Uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
 # Pre-built configuration
 # See scripts\pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
@@ -29,10 +32,7 @@
 # File extensions
 O=.obj
 
-#uncomment next to put error messages in a file
-#ERRFILE= >> pngerrs.log
-
-# Variables
+# File lists
 OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
 OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
 OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
@@ -47,39 +47,39 @@
 png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
@@ -93,14 +93,14 @@
 	-$(RM) $@
 	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
 
-pngtest$(O): png.h pngconf.h pnglibconf.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
 pngtest.exe: pngtest$(O) libpng.lib
 	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
 
+pngtest$(O): png.h pngconf.h pnglibconf.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 test: pngtest.exe
-	pngtest
+	pngtest.exe
 
 clean:
 	-$(RM) *$(O)
@@ -110,4 +110,3 @@
 	-$(RM) pngout.png
 
 # End of makefile for libpng
-
diff --git a/scripts/pnglibconf.dfa b/scripts/pnglibconf.dfa
index 4dcaf7c..0ada967 100644
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -8,7 +8,7 @@
 com
 version
 com
-com Copyright (c) 2018-2019 Cosmin Truta
+com Copyright (c) 2018-2022 Cosmin Truta
 com Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
 com
 com This code is released under the libpng license.
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index e1e27e9..89d5b4c 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -1,8 +1,8 @@
 /* pnglibconf.h - library build configuration */
 
-/* libpng version 1.6.37 */
+/* libpng version 1.6.38 */
 
-/* Copyright (c) 2018-2019 Cosmin Truta */
+/* Copyright (c) 2018-2022 Cosmin Truta */
 /* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson */
 
 /* This code is released under the libpng license. */
diff --git a/scripts/pnglibconf.mak b/scripts/pnglibconf.mak
index c125ca2..34a240e 100755
--- a/scripts/pnglibconf.mak
+++ b/scripts/pnglibconf.mak
@@ -11,12 +11,12 @@
 AWK = mawk
 AWK = nawk
 AWK = one-true-awk
-AWK = awk  # Crashes on SunOS 5.10 - use 'nawk'
-CPP = $(CC) -E # On SUN OS 5.10 if this causes problems use /lib/cpp
+AWK = awk      # This fails on SunOS 5.10; use 'nawk'
+CPP = $(CC) -E # If this fails on SunOS 5.10, use '/lib/cpp'
 
-MOVE = mv
+MOVE = mv -f
 DELETE = rm -f
-ECHO = echo
+
 DFA_XTRA = # Put your configuration file here, see scripts/pnglibconf.dfa.  Eg:
 # DFA_XTRA = pngusr.dfa
 
@@ -25,27 +25,27 @@
 # as appropriate
 DFNFLAGS = $(DEFS) $(CPPFLAGS) $(CFLAGS)
 
-# srcdir is a defacto standard for the location of the source
+# srcdir is a de-facto standard for the location of the source
 srcdir = .
 
 # The standard pnglibconf.h exists as scripts/pnglibconf.h.prebuilt,
 # copy this if the following doesn't work.
 pnglibconf.h: pnglibconf.dfn
 	$(DELETE) $@ pnglibconf.c pnglibconf.out pnglibconf.tmp
-	$(ECHO) '#include "pnglibconf.dfn"' >pnglibconf.c
-	$(ECHO) "If '$(CC) -E' crashes try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
+	echo '#include "pnglibconf.dfn"' >pnglibconf.c
+	@echo "## If '$(CC) -E' fails, try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
 	$(CPP) $(DFNFLAGS) pnglibconf.c >pnglibconf.out
-	$(AWK) -f "$(srcdir)/scripts/dfn.awk" out="pnglibconf.tmp" pnglibconf.out 1>&2
+	$(AWK) -f $(srcdir)/scripts/dfn.awk out=pnglibconf.tmp pnglibconf.out >&2
 	$(MOVE) pnglibconf.tmp $@
 
 pnglibconf.dfn: $(srcdir)/scripts/pnglibconf.dfa $(srcdir)/scripts/options.awk $(srcdir)/pngconf.h $(srcdir)/pngusr.dfa $(DFA_XTRA)
 	$(DELETE) $@ pnglibconf.pre pnglibconf.tmp
-	$(ECHO) "Calling $(AWK) from scripts/pnglibconf.mak" >&2
-	$(ECHO) "If 'awk' crashes try a better awk (e.g. AWK='nawk')" >&2
-	$(AWK) -f $(srcdir)/scripts/options.awk out="pnglibconf.pre"\
+	@echo "## Calling $(AWK) from scripts/pnglibconf.mak" >&2
+	@echo "## If 'awk' fails, try a better awk (e.g. AWK='nawk')" >&2
+	$(AWK) -f $(srcdir)/scripts/options.awk out=pnglibconf.pre\
 	    version=search $(srcdir)/pngconf.h $(srcdir)/scripts/pnglibconf.dfa\
-	    $(srcdir)/pngusr.dfa $(DFA_XTRA) 1>&2
-	$(AWK) -f $(srcdir)/scripts/options.awk out="pnglibconf.tmp" pnglibconf.pre 1>&2
+	    $(srcdir)/pngusr.dfa $(DFA_XTRA) >&2
+	$(AWK) -f $(srcdir)/scripts/options.awk out=pnglibconf.tmp pnglibconf.pre >&2
 	$(MOVE) pnglibconf.tmp $@
 
 clean-pnglibconf:
diff --git a/scripts/smakefile.ppc b/scripts/smakefile.ppc
index 2e7380b..2fa5b65 100644
--- a/scripts/smakefile.ppc
+++ b/scripts/smakefile.ppc
@@ -19,9 +19,9 @@
 RM       = delete quiet
 MKDIR    = makedir
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o pngread.o \
-       pngerror.o pngpread.o pngwrite.o pngrtran.o pngwtran.o pngrio.o \
-       pngwio.o pngmem.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 all: $(LIBNAME) pngtest
 
diff --git a/test-driver b/test-driver
index b8521a4..be73b80 100755
--- a/test-driver
+++ b/test-driver
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 2011-2018 Free Software Foundation, Inc.
+# Copyright (C) 2011-2021 Free Software Foundation, Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -42,11 +42,13 @@
 {
   cat <<END
 Usage:
-  test-driver --test-name=NAME --log-file=PATH --trs-file=PATH
-              [--expect-failure={yes|no}] [--color-tests={yes|no}]
-              [--enable-hard-errors={yes|no}] [--]
+  test-driver --test-name NAME --log-file PATH --trs-file PATH
+              [--expect-failure {yes|no}] [--color-tests {yes|no}]
+              [--enable-hard-errors {yes|no}] [--]
               TEST-SCRIPT [TEST-SCRIPT-ARGUMENTS]
+
 The '--test-name', '--log-file' and '--trs-file' options are mandatory.
+See the GNU Automake documentation for information.
 END
 }
 
@@ -103,8 +105,11 @@
 trap "st=141; $do_exit" 13
 trap "st=143; $do_exit" 15
 
-# Test script is run here.
-"$@" >$log_file 2>&1
+# Test script is run here. We create the file first, then append to it,
+# to ameliorate tests themselves also writing to the log file. Our tests
+# don't, but others can (automake bug#35762).
+: >"$log_file"
+"$@" >>"$log_file" 2>&1
 estatus=$?
 
 if test $enable_hard_errors = no && test $estatus -eq 99; then
@@ -126,7 +131,7 @@
 # know whether the test passed or failed simply by looking at the '.log'
 # file, without the need of also peaking into the corresponding '.trs'
 # file (automake bug#11814).
-echo "$res $test_name (exit status: $estatus)" >>$log_file
+echo "$res $test_name (exit status: $estatus)" >>"$log_file"
 
 # Report outcome to console.
 echo "${col}${res}${std}: $test_name"
diff --git a/tests/pngtest b/tests/pngtest
deleted file mode 100755
index 813973b..0000000
--- a/tests/pngtest
+++ /dev/null
@@ -1,2 +0,0 @@
-#!/bin/sh
-exec ./pngtest --strict ${srcdir}/pngtest.png
diff --git a/tests/pngtest-badpngs b/tests/pngtest-all
similarity index 80%
rename from tests/pngtest-badpngs
rename to tests/pngtest-all
index 7777523..5e96451 100755
--- a/tests/pngtest-badpngs
+++ b/tests/pngtest-all
@@ -1,5 +1,9 @@
 #!/bin/sh
 
+# normal execution
+
+./pngtest --strict ${srcdir}/pngtest.png
+
 # various crashers
 # using --relaxed because some come from fuzzers that don't maintain CRC's
 
@@ -9,5 +13,4 @@
 ./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/empty_ancillary_chunks.png
 ./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/huge_*_chunk.png \
     ${srcdir}/contrib/testpngs/crashers/huge_*safe_to_copy.png
-
-exec ./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/huge_IDAT.png
+./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/huge_IDAT.png