build/config/compiler/BUILD.gn - platform/external/chromium_org - Git at Google

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.

 # Base compiler configuration.
 config("compiler") {
   include_dirs = [ "//", root_gen_dir ]
   if (is_win) {
     cflags = [
       "/Gy",  # Enable function-level linking.
       "/GS",  # Enable buffer security checking.
       "/EHsc",  # Assume C functions can't throw exceptions and don't catch
                 # structured exceptions (only C++ ones).
     ]
   } else {
     # Common GCC compiler flags setup.
     # --------------------------------
     cflags = [
       "-fno-strict-aliasing",  # See http://crbug.com/32204
       "-fvisibility=hidden",
     ]
     cflags_c = [
     ]
     cflags_cc = [
       "-fno-exceptions",
       "-fno-threadsafe-statics",
       "-fvisibility-inlines-hidden",
     ]
     ldflags = [
     ]

     # Stack protection.
     # TODO(brettw) why do we have different values for all of these cases?
     if (is_mac) {
       cflags += "-fstack-protector-all"
     } else if (is_chromeos) {
       cflags += "-fstack-protector-strong"
     } else if (is_linux) {
       cflags += [ "-fstack-protector", "--param=ssp-buffer-size=4" ]
     }

     if (is_mac) {
       # Mac-specific compiler flags setup.
       # ----------------------------------

       # These flags are shared between the C compiler and linker.
       common_mac_flags = [
         # Set which SDK to use.
         # TODO(brettw) this needs to be configurable somehow.
         "-isysroot", "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.7.sdk",

         "-mmacosx-version-min=10.6",
       ]

       # CPU architecture.
       if (cpu_arch == "x64") {
         common_mac_flags += "-arch x86_64"
       } else if (cpu_arch == "x32") {
         common_mac_flags += "-arch i386"
       }

       cflags += common_mac_flags + [
         # Without this, the constructors and destructors of a C++ object inside
         # an Objective C struct won't be called, which is very bad.
         "-fobjc-call-cxx-cdtors",
       ]

       cflags_c += [ "-std=c99" ]
       cflags_cc += [ "-std=gnu++11" ]

       ldflags += common_mac_flags + [
         "-L.",

         # TODO(brettW) I don't understand these options.
         "-Wl,-rpath,@loader_path/.",
         "-Wl,-rpath,@loader_path/../../..",
       ]
     } else {
       # Non-Mac Posix compiler flags setup.
       # -----------------------------------

       # CPU architecture. We may or may not be doing a cross compile now, so for
       # simplicity we always explicitly set the architecture.
       if (cpu_arch == "x64") {
         cflags += "-m64"
         ldflags += "-m64"
       } else if (cpu_arch == "x32") {
         cflags += "-m32"
         ldflags += "-m32"
       }
     }

     # Linux-specific compiler flags setup.
     # ------------------------------------
     if (is_linux) {
       cflags += [
         "-fPIC",
         "-pthread",
         "-pipe",  # Use pipes for communicating between sub-processes. Faster.
       ]

       # Use gold for linking on 64-bit Linux only (on 32-bit it runs out of
       # address space, and it doesn't support cross-compiling).
       if (cpu_arch == "x64") {
         gold_path = rebase_path("//third_party/gold", ".", root_build_dir)
         ldflags += [
           "-B$gold_path",

           # There seems to be a conflict of --icf and -pie in gold which can
           # generate crashy binaries. As a security measure, -pie takes
           # precendence for now.
           # TODO(brettw) common.gypi has this only for target toolset.
           #"-Wl,--icf=safe",
           "-Wl,--icf=none",

           # Experimentation found that using four linking threads
           # saved ~20% of link time.
           # https://groups.google.com/a/chromium.org/group/chromium-dev/browse_thread/thread/281527606915bb36
           # Only apply this to the target linker, since the host
           # linker might not be gold, but isn't used much anyway.
           "-Wl,--threads",
           "-Wl,--thread-count=4",
         ]
       }

       ldflags += [
         "-fPIC",
         "-pthread",
         "-Wl,-z,noexecstack",
         "-Wl,-z,now",
         "-Wl,-z,relro",
       ]
     }

     # Clang-specific compiler flags setup.
     # ------------------------------------
     if (is_clang) {
       cflags += [
         "-fcolor-diagnostics",
       ]
     }
   }
 }

 # runtime_library -------------------------------------------------------------
 #
 # Sets the runtime library and associated options.
 #
 # We don't bother making multiple versions that are toggle-able since there
 # is more than one axis of control (which makes it complicated) and there's
 # no practical reason for anybody to change this since the CRT must agree.

 config("runtime_library") {
   if (is_component_build) {
     # Component mode: dynamic CRT.
     defines = [ "COMPONENT_BUILD" ]
     if (is_win) {
       # Since the library is shared, it requires exceptions or will give errors
       # about things not matching, so keep exceptions on.
       if (is_debug) {
         cflags = [ "/MDd" ]
       } else {
         cflags = [ "/MD" ]
       }
     }
   } else {
     # Static CRT.
     if (is_win) {
       # We don't use exceptions, and when we link statically we can just get
       # rid of them entirely.
       defines = [ "_HAS_EXCEPTIONS=0" ]
       if (is_debug) {
         cflags = [ "/MTd" ]
       } else {
         cflags = [ "/MT" ]
       }
     }
   }

   if (is_win) {
     defines += [
       "__STD_C",
       "__STDC_CONSTANT_MACROS",
       "__STDC_FORMAT_MACROS",
       "_CRT_RAND_S",
       "_CRT_SECURE_NO_DEPRECATE",
       "_SCL_SECURE_NO_DEPRECATE",
       "_UNICODE",
       "UNICODE",
     ]
   }
 }

 # chromium_code ---------------------------------------------------------------
 #
 # Toggles between higher and lower warnings for code that is (or isn't)
 # part of Chromium.

 config("chromium_code") {
   if (is_win) {
     cflags = [
       "/W4",  # Warning level 4.
       "/WX",  # Treat warnings as errors.
     ]
   } else {
     cflags = [
       "-Wall",
       "-Werror",

       # GCC turns on -Wsign-compare for C++ under -Wall, but clang doesn't,
       # so we specify it explicitly.
       # TODO(fischman): remove this if http://llvm.org/PR10448 obsoletes it.
       # http://code.google.com/p/chromium/issues/detail?id=90453
       "-Wsign-compare",
     ]

     # In Chromium code, we define __STDC_foo_MACROS in order to get the
     # C99 macros on Mac and Linux.
     defines = [
       "__STDC_CONSTANT_MACROS",
       "__STDC_FORMAT_MACROS",
     ]

     # TODO(brettw) this should also be enabled on Linux but some files
     # currently fail.
     if (is_mac) {
       cflags += "-Wextra"
     }
   }
 }
 config("no_chromium_code") {
   if (is_win) {
     cflags = [
       "/W3",  # Warning level 3.
       "/wd4800",  # Disable warning when forcing value to bool.
     ]
     defines = [
       "_CRT_NONSTDC_NO_WARNINGS",
       "_CRT_NONSTDC_NO_DEPRECATE",
     ]
   }
 }

 # rtti ------------------------------------------------------------------------
 #
 # Allows turning Run-Time Type Identification on or off.

 config("rtti") {
   if (is_win) {
     cflags_cc = [ "/GR" ]
   }
 }
 config("no_rtti") {
   if (is_win) {
     cflags_cc = [ "/GR-" ]
   } else {
     cflags_cc = [ "-fno-rtti" ]
   }
 }

 # Warnings ---------------------------------------------------------------------

 config("default_warnings") {
   if (is_win) {
     # Please keep ordered and add names if you add more.
     cflags = [
       "/wd4018",  # Comparing signed and unsigned values.
       "/wd4100",  # Unreferenced formal function parameter.
       "/wd4121",  # Alignment of a member was sensitive to packing.
       "/wd4125",  # Decimal digit terminates octal escape sequence.
       "/wd4127",  # Conditional expression is constant.
       "/wd4130",  # Logical operation on address of string constant.
       # TODO(brettw) is this necessary? If so, it should probably be on whoever
       # is silly enough to be doing this rather than globally.
       #"/wd4131",  # Function uses old-style declarator.
       "/wd4189",  # A variable was declared and initialized but never used.
       "/wd4201",  # Nonstandard extension used: nameless struct/union.
       "/wd4238",  # Nonstandard extension used: class rvalue used as lvalue.
       "/wd4244",  # Conversion: possible loss of data.
       "/wd4245",  # Conversion: signed/unsigned mismatch,
       "/wd4251",  # Class needs to have dll-interface.
       "/wd4310",  # Cast truncates constant value.
       "/wd4351",  # Elements of array will be default initialized.
       "/wd4355",  # 'this' used in base member initializer list.
       "/wd4396",  # Inline friend template thing.
       "/wd4428",  # Universal character name encountered in source.
       "/wd4481",  # Nonstandard extension: override specifier.
       "/wd4503",  # Decorated name length exceeded, name was truncated.
       "/wd4505",  # Unreferenced local function has been removed.
       "/wd4510",  # Default constructor could not be generated.
       "/wd4512",  # Assignment operator could not be generated.
       "/wd4530",  # Exception handler used, but unwind semantics not enabled.
       "/wd4610",  # Class can never be instantiated, constructor required.
       "/wd4611",  # C++ object destruction and 'catch'.
       "/wd4701",  # Potentially uninitialized local variable name used.
       "/wd4702",  # Unreachable code.
       "/wd4706",  # Assignment within conditional expression.
       "/wd4819",  # Character not in the current code page.
     ]
   } else {
     # Common GCC warning setup.
     cflags = [
       # Enables.
       "-Wendif-labels",  # Weird old-style text after an #endif.

       # Disables.
       "-Wno-missing-field-initializers",  # "struct foo f = {0};"
       "-Wno-unused-parameter",  # Unused function parameters.
       "-Wno-write-strings",
     ]

     if (is_mac) {
       cflags += [
         "-Wnewline-eof",
       ]
     }

     # TODO(brettw) Ones below here should be clang-only when we have a flag
     # for it.
     if (is_clang) {
       cflags += [
         "-Wheader-hygiene",

         # This warns on using ints as initializers for floats in
         # initializer lists (e.g. |int a = f(); CGSize s = { a, a };|),
         # which happens in several places in chrome code. Not sure if
         # this is worth fixing.
         "-Wno-c++11-narrowing",

         # Don't die on dtoa code that uses a char as an array index.
         # This is required solely for base/third_party/dmg_fp/dtoa.cc.
         # TODO(brettw) move this to that project then!
         "-Wno-char-subscripts",

         # Warns on switches on enums that cover all enum values but
         # also contain a default: branch. Chrome is full of that.
         "-Wno-covered-switch-default",

         # Clang considers the `register` keyword as deprecated, but e.g.
         # code generated by flex (used in angle) contains that keyword.
         # http://crbug.com/255186
         "-Wno-deprecated-register",

         # Clang spots more unused functions.
         "-Wno-unused-function",

         # Warns when a const char[] is converted to bool.
         "-Wstring-conversion",
       ]
     }
   }
 }

 # Optimization -----------------------------------------------------------------

 config("optimize") {
   if (is_win) {
     cflags = [
       "/O2",
       "/Ob2",  # Both explicit and auto inlining.
       "/Oy-",  # Disable omitting frame pointers, must be after /O2.
     ]
   } else {
     if (is_ios) {
       cflags = [ "-Os" ]
     } else {
       cflags = [ "-O2" ]
     }
   }
 }

 config("no_optimize") {
   if (is_win) {
     cflags = [
       "/Od",  # Disable optimization.
       "/Ob0",  # Disable all inlining (on by default).
       "/RTC1",  # Runtime checks for stack frame and uninitialized variables.
     ]
   } else {
     cflags = [ "-O0" ]
   }
 }

 # Symbols ----------------------------------------------------------------------

 # TODO(brettw) Since this sets ldflags on Windows which is inherited across
 # static library boundaries, if you want to remove the default symbol config
 # and set a different one on a target, you also have to do it for all static
 # libraries that go into that target, which is messed up. Either we need a
 # more flexible system for defining linker flags, or we need to separate this
 # out into a "symbols_linker" config that is only applied to DLLs and EXEs.
 config("symbols") {
   if (is_win) {
     cflags = [ "/Zi" ]  # Produce PDB file, no edit and continue.
     ldflags = [ "/DEBUG" ]
   } else {
     cflags = [ "-g2" ]
   }
 }

 config("minimal_symbols") {
   if (is_win) {
     # Linker symbols for backtraces only.
     ldflags = [ "/DEBUG" ]
   } else {
     cflags = [ "-g1" ]
   }
 }

 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }
	# Copyright (c) 2013 The Chromium Authors. All rights reserved.
	# Use of this source code is governed by a BSD-style license that can be
	# found in the LICENSE file.

	# Base compiler configuration.
	config("compiler") {
	include_dirs = [ "//", root_gen_dir ]
	if (is_win) {
	cflags = [
	"/Gy", # Enable function-level linking.
	"/GS", # Enable buffer security checking.
	"/EHsc", # Assume C functions can't throw exceptions and don't catch
	# structured exceptions (only C++ ones).
	]
	} else {
	# Common GCC compiler flags setup.
	# --------------------------------
	cflags = [
	"-fno-strict-aliasing", # See http://crbug.com/32204
	"-fvisibility=hidden",
	]
	cflags_c = [
	]
	cflags_cc = [
	"-fno-exceptions",
	"-fno-threadsafe-statics",
	"-fvisibility-inlines-hidden",
	]
	ldflags = [
	]

	# Stack protection.
	# TODO(brettw) why do we have different values for all of these cases?
	if (is_mac) {
	cflags += "-fstack-protector-all"
	} else if (is_chromeos) {
	cflags += "-fstack-protector-strong"
	} else if (is_linux) {
	cflags += [ "-fstack-protector", "--param=ssp-buffer-size=4" ]
	}

	if (is_mac) {
	# Mac-specific compiler flags setup.
	# ----------------------------------

	# These flags are shared between the C compiler and linker.
	common_mac_flags = [
	# Set which SDK to use.
	# TODO(brettw) this needs to be configurable somehow.
	"-isysroot", "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.7.sdk",

	"-mmacosx-version-min=10.6",
	]

	# CPU architecture.
	if (cpu_arch == "x64") {
	common_mac_flags += "-arch x86_64"
	} else if (cpu_arch == "x32") {
	common_mac_flags += "-arch i386"
	}

	cflags += common_mac_flags + [
	# Without this, the constructors and destructors of a C++ object inside
	# an Objective C struct won't be called, which is very bad.
	"-fobjc-call-cxx-cdtors",
	]

	cflags_c += [ "-std=c99" ]
	cflags_cc += [ "-std=gnu++11" ]

	ldflags += common_mac_flags + [
	"-L.",

	# TODO(brettW) I don't understand these options.
	"-Wl,-rpath,@loader_path/.",
	"-Wl,-rpath,@loader_path/../../..",
	]
	} else {
	# Non-Mac Posix compiler flags setup.
	# -----------------------------------

	# CPU architecture. We may or may not be doing a cross compile now, so for
	# simplicity we always explicitly set the architecture.
	if (cpu_arch == "x64") {
	cflags += "-m64"
	ldflags += "-m64"
	} else if (cpu_arch == "x32") {
	cflags += "-m32"
	ldflags += "-m32"
	}
	}

	# Linux-specific compiler flags setup.
	# ------------------------------------
	if (is_linux) {
	cflags += [
	"-fPIC",
	"-pthread",
	"-pipe", # Use pipes for communicating between sub-processes. Faster.
	]

	# Use gold for linking on 64-bit Linux only (on 32-bit it runs out of
	# address space, and it doesn't support cross-compiling).
	if (cpu_arch == "x64") {
	gold_path = rebase_path("//third_party/gold", ".", root_build_dir)
	ldflags += [
	"-B$gold_path",

	# There seems to be a conflict of --icf and -pie in gold which can
	# generate crashy binaries. As a security measure, -pie takes
	# precendence for now.
	# TODO(brettw) common.gypi has this only for target toolset.
	#"-Wl,--icf=safe",
	"-Wl,--icf=none",

	# Experimentation found that using four linking threads
	# saved ~20% of link time.
	# https://groups.google.com/a/chromium.org/group/chromium-dev/browse_thread/thread/281527606915bb36
	# Only apply this to the target linker, since the host
	# linker might not be gold, but isn't used much anyway.
	"-Wl,--threads",
	"-Wl,--thread-count=4",
	]
	}

	ldflags += [
	"-fPIC",
	"-pthread",
	"-Wl,-z,noexecstack",
	"-Wl,-z,now",
	"-Wl,-z,relro",
	]
	}

	# Clang-specific compiler flags setup.
	# ------------------------------------
	if (is_clang) {
	cflags += [
	"-fcolor-diagnostics",
	]
	}
	}
	}

	# runtime_library -------------------------------------------------------------
	#
	# Sets the runtime library and associated options.
	#
	# We don't bother making multiple versions that are toggle-able since there
	# is more than one axis of control (which makes it complicated) and there's
	# no practical reason for anybody to change this since the CRT must agree.

	config("runtime_library") {
	if (is_component_build) {
	# Component mode: dynamic CRT.
	defines = [ "COMPONENT_BUILD" ]
	if (is_win) {
	# Since the library is shared, it requires exceptions or will give errors
	# about things not matching, so keep exceptions on.
	if (is_debug) {
	cflags = [ "/MDd" ]
	} else {
	cflags = [ "/MD" ]
	}
	}
	} else {
	# Static CRT.
	if (is_win) {
	# We don't use exceptions, and when we link statically we can just get
	# rid of them entirely.
	defines = [ "_HAS_EXCEPTIONS=0" ]
	if (is_debug) {
	cflags = [ "/MTd" ]
	} else {
	cflags = [ "/MT" ]
	}
	}
	}

	if (is_win) {
	defines += [
	"__STD_C",
	"__STDC_CONSTANT_MACROS",
	"__STDC_FORMAT_MACROS",
	"_CRT_RAND_S",
	"_CRT_SECURE_NO_DEPRECATE",
	"_SCL_SECURE_NO_DEPRECATE",
	"_UNICODE",
	"UNICODE",
	]
	}
	}

	# chromium_code ---------------------------------------------------------------
	#
	# Toggles between higher and lower warnings for code that is (or isn't)
	# part of Chromium.

	config("chromium_code") {
	if (is_win) {
	cflags = [
	"/W4", # Warning level 4.
	"/WX", # Treat warnings as errors.
	]
	} else {
	cflags = [
	"-Wall",
	"-Werror",

	# GCC turns on -Wsign-compare for C++ under -Wall, but clang doesn't,
	# so we specify it explicitly.
	# TODO(fischman): remove this if http://llvm.org/PR10448 obsoletes it.
	# http://code.google.com/p/chromium/issues/detail?id=90453
	"-Wsign-compare",
	]

	# In Chromium code, we define __STDC_foo_MACROS in order to get the
	# C99 macros on Mac and Linux.
	defines = [
	"__STDC_CONSTANT_MACROS",
	"__STDC_FORMAT_MACROS",
	]

	# TODO(brettw) this should also be enabled on Linux but some files
	# currently fail.
	if (is_mac) {
	cflags += "-Wextra"
	}
	}
	}
	config("no_chromium_code") {
	if (is_win) {
	cflags = [
	"/W3", # Warning level 3.
	"/wd4800", # Disable warning when forcing value to bool.
	]
	defines = [
	"_CRT_NONSTDC_NO_WARNINGS",
	"_CRT_NONSTDC_NO_DEPRECATE",
	]
	}
	}

	# rtti ------------------------------------------------------------------------
	#
	# Allows turning Run-Time Type Identification on or off.

	config("rtti") {
	if (is_win) {
	cflags_cc = [ "/GR" ]
	}
	}
	config("no_rtti") {
	if (is_win) {
	cflags_cc = [ "/GR-" ]
	} else {
	cflags_cc = [ "-fno-rtti" ]
	}
	}

	# Warnings ---------------------------------------------------------------------

	config("default_warnings") {
	if (is_win) {
	# Please keep ordered and add names if you add more.
	cflags = [
	"/wd4018", # Comparing signed and unsigned values.
	"/wd4100", # Unreferenced formal function parameter.
	"/wd4121", # Alignment of a member was sensitive to packing.
	"/wd4125", # Decimal digit terminates octal escape sequence.
	"/wd4127", # Conditional expression is constant.
	"/wd4130", # Logical operation on address of string constant.
	# TODO(brettw) is this necessary? If so, it should probably be on whoever
	# is silly enough to be doing this rather than globally.
	#"/wd4131", # Function uses old-style declarator.
	"/wd4189", # A variable was declared and initialized but never used.
	"/wd4201", # Nonstandard extension used: nameless struct/union.
	"/wd4238", # Nonstandard extension used: class rvalue used as lvalue.
	"/wd4244", # Conversion: possible loss of data.
	"/wd4245", # Conversion: signed/unsigned mismatch,
	"/wd4251", # Class needs to have dll-interface.
	"/wd4310", # Cast truncates constant value.
	"/wd4351", # Elements of array will be default initialized.
	"/wd4355", # 'this' used in base member initializer list.
	"/wd4396", # Inline friend template thing.
	"/wd4428", # Universal character name encountered in source.
	"/wd4481", # Nonstandard extension: override specifier.
	"/wd4503", # Decorated name length exceeded, name was truncated.
	"/wd4505", # Unreferenced local function has been removed.
	"/wd4510", # Default constructor could not be generated.
	"/wd4512", # Assignment operator could not be generated.
	"/wd4530", # Exception handler used, but unwind semantics not enabled.
	"/wd4610", # Class can never be instantiated, constructor required.
	"/wd4611", # C++ object destruction and 'catch'.
	"/wd4701", # Potentially uninitialized local variable name used.
	"/wd4702", # Unreachable code.
	"/wd4706", # Assignment within conditional expression.
	"/wd4819", # Character not in the current code page.
	]
	} else {
	# Common GCC warning setup.
	cflags = [
	# Enables.
	"-Wendif-labels", # Weird old-style text after an #endif.

	# Disables.
	"-Wno-missing-field-initializers", # "struct foo f = {0};"
	"-Wno-unused-parameter", # Unused function parameters.
	"-Wno-write-strings",
	]

	if (is_mac) {
	cflags += [
	"-Wnewline-eof",
	]
	}

	# TODO(brettw) Ones below here should be clang-only when we have a flag
	# for it.
	if (is_clang) {
	cflags += [
	"-Wheader-hygiene",

	# This warns on using ints as initializers for floats in
	# initializer lists (e.g. \|int a = f(); CGSize s = { a, a };\|),
	# which happens in several places in chrome code. Not sure if
	# this is worth fixing.
	"-Wno-c++11-narrowing",

	# Don't die on dtoa code that uses a char as an array index.
	# This is required solely for base/third_party/dmg_fp/dtoa.cc.
	# TODO(brettw) move this to that project then!
	"-Wno-char-subscripts",

	# Warns on switches on enums that cover all enum values but
	# also contain a default: branch. Chrome is full of that.
	"-Wno-covered-switch-default",

	# Clang considers the `register` keyword as deprecated, but e.g.
	# code generated by flex (used in angle) contains that keyword.
	# http://crbug.com/255186
	"-Wno-deprecated-register",

	# Clang spots more unused functions.
	"-Wno-unused-function",

	# Warns when a const char[] is converted to bool.
	"-Wstring-conversion",
	]
	}
	}
	}

	# Optimization -----------------------------------------------------------------

	config("optimize") {
	if (is_win) {
	cflags = [
	"/O2",
	"/Ob2", # Both explicit and auto inlining.
	"/Oy-", # Disable omitting frame pointers, must be after /O2.
	]
	} else {
	if (is_ios) {
	cflags = [ "-Os" ]
	} else {
	cflags = [ "-O2" ]
	}
	}
	}

	config("no_optimize") {
	if (is_win) {
	cflags = [
	"/Od", # Disable optimization.
	"/Ob0", # Disable all inlining (on by default).
	"/RTC1", # Runtime checks for stack frame and uninitialized variables.
	]
	} else {
	cflags = [ "-O0" ]
	}
	}

	# Symbols ----------------------------------------------------------------------

	# TODO(brettw) Since this sets ldflags on Windows which is inherited across
	# static library boundaries, if you want to remove the default symbol config
	# and set a different one on a target, you also have to do it for all static
	# libraries that go into that target, which is messed up. Either we need a
	# more flexible system for defining linker flags, or we need to separate this
	# out into a "symbols_linker" config that is only applied to DLLs and EXEs.
	config("symbols") {
	if (is_win) {
	cflags = [ "/Zi" ] # Produce PDB file, no edit and continue.
	ldflags = [ "/DEBUG" ]
	} else {
	cflags = [ "-g2" ]
	}
	}

	config("minimal_symbols") {
	if (is_win) {
	# Linker symbols for backtraces only.
	ldflags = [ "/DEBUG" ]
	} else {
	cflags = [ "-g1" ]
	}
	}

	config("no_symbols") {
	if (!is_win) {
	cflags = [ "-g0" ]
	}
	}