core/combo/linux-arm.mk - platform/build - Git at Google

 # Configuration for Linux on ARM.
 # Included by combo/select.make

 # You can set TARGET_ARCH_VERSION to use an arch version other
 # than ARMv5TE
 ifeq ($(strip $(TARGET_ARCH_VERSION)),)
 TARGET_ARCH_VERSION := armv5te
 endif

 # This set of if blocks sets makefile variables similar to preprocesser
 # defines in system/core/include/arch/<combo>/AndroidConfig.h. Their
 # purpose is to allow module Android.mk files to selctively compile
 # different versions of code based upon the funtionality and
 # instructions available in a given architecture version.
 #
 # The blocks also define specific arch_version_cflags, which
 # include defines, and compiler settings for the given architecture
 # version.
 #
 # Note: Hard coding the 'tune' value here is probably not ideal,
 # and a better solution should be found in the future.
 #
 # With two or three different versions this if block approach is
 # fine. If/when this becomes large, please change this to include
 # architecture versions specific Makefiles which define these
 # variables.
 #
 ifeq ($(TARGET_ARCH_VERSION),armv5te)
 ARCH_ARM_HAVE_THUMB_SUPPORT := true
 ARCH_ARM_HAVE_FAST_INTERWORKING := true
 ARCH_ARM_HAVE_64BIT_DATA := true
 ARCH_ARM_HAVE_HALFWORD_MULTIPLY := true
 ARCH_ARM_HAVE_CLZ := true
 ARCH_ARM_HAVE_FFS := true

 arch_version_cflags := -march=armv5te -mtune=xscale  -D__ARM_ARCH_5__ \
 	-D__ARM_ARCH_5T__ -D__ARM_ARCH_5TE__
 else
 ifeq ($(TARGET_ARCH_VERSION),armv4)
 $(warning ARMv4 support is currently a work in progress. It does not work right now!)
 ARCH_ARM_HAVE_THUMB_SUPPORT := false
 ARCH_ARM_HAVE_THUMB_INTERWORKING := false
 ARCH_ARM_HAVE_64BIT_DATA := false
 ARCH_ARM_HAVE_HALFWORD_MULTIPLY := false
 ARCH_ARM_HAVE_CLZ := false
 ARCH_ARM_HAVE_FFS := false

 DEFAULT_TARGET_CPU := arm920

 arch_version_cflags := -march=armv4 -mtune=arm920 -D__ARM_ARCH_4__
 else
 $(error Unknown ARM architecture version: $(TARGET_ARCH_VERSION))
 endif
 endif

 # You can set TARGET_TOOLS_PREFIX to get gcc from somewhere else
 ifeq ($(strip $($(combo_target)TOOLS_PREFIX)),)
 $(combo_target)TOOLS_PREFIX := \
 	prebuilt/$(HOST_PREBUILT_TAG)/toolchain/arm-eabi-4.2.1/bin/arm-eabi-
 endif

 $(combo_target)CC := $($(combo_target)TOOLS_PREFIX)gcc$(HOST_EXECUTABLE_SUFFIX)
 $(combo_target)CXX := $($(combo_target)TOOLS_PREFIX)g++$(HOST_EXECUTABLE_SUFFIX)
 $(combo_target)AR := $($(combo_target)TOOLS_PREFIX)ar$(HOST_EXECUTABLE_SUFFIX)
 $(combo_target)OBJCOPY := $($(combo_target)TOOLS_PREFIX)objcopy$(HOST_EXECUTABLE_SUFFIX)
 $(combo_target)LD := $($(combo_target)TOOLS_PREFIX)ld$(HOST_EXECUTABLE_SUFFIX)

 $(combo_target)NO_UNDEFINED_LDFLAGS := -Wl,--no-undefined

 TARGET_arm_release_CFLAGS :=    -fomit-frame-pointer \
                                 -fstrict-aliasing    \
                                 -funswitch-loops     \
                                 -finline-limit=300

 # Modules can choose to compile some source as thumb. As
 # non-thumb enabled targets are supported, this is treated
 # as a 'hint'. If thumb is not enabled, these files are just
 # compiled as ARM.
 ifeq ($(ARCH_ARM_HAVE_THUMB_SUPPORT),true)
 TARGET_thumb_release_CFLAGS :=  -mthumb \
                                 -Os \
                                 -fomit-frame-pointer \
                                 -fno-strict-aliasing \
                                 -finline-limit=64
 else
 TARGET_thumb_release_CFLAGS := $(TARGET_arm_release_CFLAGS)
 endif

 # When building for debug, compile everything as arm.
 TARGET_arm_debug_CFLAGS := $(TARGET_arm_release_CFLAGS) -fno-omit-frame-pointer -fno-strict-aliasing
 TARGET_thumb_debug_CFLAGS := $(TARGET_thumb_release_CFLAGS) -marm -fno-omit-frame-pointer

 # NOTE: if you try to build a debug build with thumb, several
 # of the libraries (libpv, libwebcore, libkjs) need to be built
 # with -mlong-calls.  When built at -O0, those libraries are
 # too big for a thumb "BL <label>" to go from one end to the other.

 ## As hopefully a temporary hack,
 ## use this to force a full ARM build (for easier debugging in gdb)
 ## (don't forget to do a clean build)
 ##TARGET_arm_release_CFLAGS := $(TARGET_arm_release_CFLAGS) -fno-omit-frame-pointer
 ##TARGET_thumb_release_CFLAGS := $(TARGET_thumb_release_CFLAGS) -marm -fno-omit-frame-pointer

 android_config_h := $(call select-android-config-h,linux-arm)
 arch_include_dir := $(dir $(android_config_h))

 $(combo_target)GLOBAL_CFLAGS += \
 			-msoft-float -fpic \
 			-ffunction-sections \
 			-funwind-tables \
 			-fstack-protector \
 			-fno-short-enums \
 			$(arch_version_cflags) \
 			-include $(android_config_h) \
 			-I $(arch_include_dir)

 # We only need thumb interworking in cases where thumb support
 # is available in the architecture, and just to be sure, (and
 # since sometimes thumb-interwork appears to be default), we
 # specifically disable when thumb support is unavailable.
 ifeq ($(ARCH_ARM_HAVE_THUMB_SUPPORT),true)
 $(combo_target)GLOBAL_CFLAGS +=	-mthumb-interwork
 else
 $(combo_target)GLOBAL_CFLAGS +=	-mno-thumb-interwork
 endif

 $(combo_target)GLOBAL_CPPFLAGS += -fvisibility-inlines-hidden

 $(combo_target)RELEASE_CFLAGS := \
 			-DSK_RELEASE -DNDEBUG \
 			-O2 -g \
 			-Wstrict-aliasing=2 \
 			-finline-functions \
 			-fno-inline-functions-called-once \
 			-fgcse-after-reload \
 			-frerun-cse-after-loop \
 			-frename-registers

 libc_root := bionic/libc
 libm_root := bionic/libm
 libstdc++_root := bionic/libstdc++
 libthread_db_root := bionic/libthread_db


 ## on some hosts, the target cross-compiler is not available so do not run this command
 ifneq ($(wildcard $($(combo_target)CC)),)
 # We compile with the global cflags to ensure that
 # any flags which affect libgcc are correctly taken
 # into account.
 $(combo_target)LIBGCC := $(shell $($(combo_target)CC) $($(combo_target)GLOBAL_CFLAGS) -print-libgcc-file-name)
 endif

 # unless CUSTOM_KERNEL_HEADERS is defined, we're going to use
 # symlinks located in out/ to point to the appropriate kernel
 # headers. see 'config/kernel_headers.make' for more details
 #
 ifneq ($(CUSTOM_KERNEL_HEADERS),)
     KERNEL_HEADERS_COMMON := $(CUSTOM_KERNEL_HEADERS)
     KERNEL_HEADERS_ARCH   := $(CUSTOM_KERNEL_HEADERS)
 else
     KERNEL_HEADERS_COMMON := $(libc_root)/kernel/common
     KERNEL_HEADERS_ARCH   := $(libc_root)/kernel/arch-$(TARGET_ARCH)
 endif
 KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)

 $(combo_target)C_INCLUDES := \
 	$(libc_root)/arch-arm/include \
 	$(libc_root)/include \
 	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/arch/arm \
 	$(libthread_db_root)/include

 TARGET_CRTBEGIN_STATIC_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_static.o
 TARGET_CRTBEGIN_DYNAMIC_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_dynamic.o
 TARGET_CRTEND_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_android.o

 TARGET_STRIP_MODULE:=true

 $(combo_target)DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm

 $(combo_target)CUSTOM_LD_COMMAND := true
 define transform-o-to-shared-lib-inner
 $(TARGET_CXX) \
 	-nostdlib -Wl,-soname,$(notdir $@) -Wl,-T,$(BUILD_SYSTEM)/armelf.xsc \
 	-Wl,--gc-sections \
 	-Wl,-shared,-Bsymbolic \
 	$(TARGET_GLOBAL_LD_DIRS) \
 	$(PRIVATE_ALL_OBJECTS) \
 	-Wl,--whole-archive \
 	$(call normalize-host-libraries,$(PRIVATE_ALL_WHOLE_STATIC_LIBRARIES)) \
 	-Wl,--no-whole-archive \
 	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
 	$(call normalize-target-libraries,$(PRIVATE_ALL_SHARED_LIBRARIES)) \
 	-o $@ \
 	$(PRIVATE_LDFLAGS) \
 	$(TARGET_LIBGCC)
 endef

 define transform-o-to-executable-inner
 $(TARGET_CXX) -nostdlib -Bdynamic -Wl,-T,$(BUILD_SYSTEM)/armelf.x \
 	-Wl,-dynamic-linker,/system/bin/linker \
     -Wl,--gc-sections \
 	-Wl,-z,nocopyreloc \
 	-o $@ \
 	$(TARGET_GLOBAL_LD_DIRS) \
 	-Wl,-rpath-link=$(TARGET_OUT_INTERMEDIATE_LIBRARIES) \
 	$(call normalize-target-libraries,$(PRIVATE_ALL_SHARED_LIBRARIES)) \
 	$(TARGET_CRTBEGIN_DYNAMIC_O) \
 	$(PRIVATE_ALL_OBJECTS) \
 	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
 	$(PRIVATE_LDFLAGS) \
 	$(TARGET_LIBGCC) \
 	$(TARGET_CRTEND_O)
 endef

 define transform-o-to-static-executable-inner
 $(TARGET_CXX) -nostdlib -Bstatic -Wl,-T,$(BUILD_SYSTEM)/armelf.x \
     -Wl,--gc-sections \
 	-o $@ \
 	$(TARGET_GLOBAL_LD_DIRS) \
 	$(TARGET_CRTBEGIN_STATIC_O) \
 	$(PRIVATE_LDFLAGS) \
 	$(PRIVATE_ALL_OBJECTS) \
 	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
 	$(TARGET_LIBGCC) \
 	$(TARGET_CRTEND_O)
 endef
	# Configuration for Linux on ARM.
	# Included by combo/select.make

	# You can set TARGET_ARCH_VERSION to use an arch version other
	# than ARMv5TE
	ifeq ($(strip $(TARGET_ARCH_VERSION)),)
	TARGET_ARCH_VERSION := armv5te
	endif

	# This set of if blocks sets makefile variables similar to preprocesser
	# defines in system/core/include/arch/<combo>/AndroidConfig.h. Their
	# purpose is to allow module Android.mk files to selctively compile
	# different versions of code based upon the funtionality and
	# instructions available in a given architecture version.
	#
	# The blocks also define specific arch_version_cflags, which
	# include defines, and compiler settings for the given architecture
	# version.
	#
	# Note: Hard coding the 'tune' value here is probably not ideal,
	# and a better solution should be found in the future.
	#
	# With two or three different versions this if block approach is
	# fine. If/when this becomes large, please change this to include
	# architecture versions specific Makefiles which define these
	# variables.
	#
	ifeq ($(TARGET_ARCH_VERSION),armv5te)
	ARCH_ARM_HAVE_THUMB_SUPPORT := true
	ARCH_ARM_HAVE_FAST_INTERWORKING := true
	ARCH_ARM_HAVE_64BIT_DATA := true
	ARCH_ARM_HAVE_HALFWORD_MULTIPLY := true
	ARCH_ARM_HAVE_CLZ := true
	ARCH_ARM_HAVE_FFS := true

	arch_version_cflags := -march=armv5te -mtune=xscale -D__ARM_ARCH_5__ \
	-D__ARM_ARCH_5T__ -D__ARM_ARCH_5TE__
	else
	ifeq ($(TARGET_ARCH_VERSION),armv4)
	$(warning ARMv4 support is currently a work in progress. It does not work right now!)
	ARCH_ARM_HAVE_THUMB_SUPPORT := false
	ARCH_ARM_HAVE_THUMB_INTERWORKING := false
	ARCH_ARM_HAVE_64BIT_DATA := false
	ARCH_ARM_HAVE_HALFWORD_MULTIPLY := false
	ARCH_ARM_HAVE_CLZ := false
	ARCH_ARM_HAVE_FFS := false

	DEFAULT_TARGET_CPU := arm920

	arch_version_cflags := -march=armv4 -mtune=arm920 -D__ARM_ARCH_4__
	else
	$(error Unknown ARM architecture version: $(TARGET_ARCH_VERSION))
	endif
	endif

	# You can set TARGET_TOOLS_PREFIX to get gcc from somewhere else
	ifeq ($(strip $($(combo_target)TOOLS_PREFIX)),)
	$(combo_target)TOOLS_PREFIX := \
	prebuilt/$(HOST_PREBUILT_TAG)/toolchain/arm-eabi-4.2.1/bin/arm-eabi-
	endif

	$(combo_target)CC := $($(combo_target)TOOLS_PREFIX)gcc$(HOST_EXECUTABLE_SUFFIX)
	$(combo_target)CXX := $($(combo_target)TOOLS_PREFIX)g++$(HOST_EXECUTABLE_SUFFIX)
	$(combo_target)AR := $($(combo_target)TOOLS_PREFIX)ar$(HOST_EXECUTABLE_SUFFIX)
	$(combo_target)OBJCOPY := $($(combo_target)TOOLS_PREFIX)objcopy$(HOST_EXECUTABLE_SUFFIX)
	$(combo_target)LD := $($(combo_target)TOOLS_PREFIX)ld$(HOST_EXECUTABLE_SUFFIX)

	$(combo_target)NO_UNDEFINED_LDFLAGS := -Wl,--no-undefined

	TARGET_arm_release_CFLAGS := -fomit-frame-pointer \
	-fstrict-aliasing \
	-funswitch-loops \
	-finline-limit=300

	# Modules can choose to compile some source as thumb. As
	# non-thumb enabled targets are supported, this is treated
	# as a 'hint'. If thumb is not enabled, these files are just
	# compiled as ARM.
	ifeq ($(ARCH_ARM_HAVE_THUMB_SUPPORT),true)
	TARGET_thumb_release_CFLAGS := -mthumb \
	-Os \
	-fomit-frame-pointer \
	-fno-strict-aliasing \
	-finline-limit=64
	else
	TARGET_thumb_release_CFLAGS := $(TARGET_arm_release_CFLAGS)
	endif

	# When building for debug, compile everything as arm.
	TARGET_arm_debug_CFLAGS := $(TARGET_arm_release_CFLAGS) -fno-omit-frame-pointer -fno-strict-aliasing
	TARGET_thumb_debug_CFLAGS := $(TARGET_thumb_release_CFLAGS) -marm -fno-omit-frame-pointer

	# NOTE: if you try to build a debug build with thumb, several
	# of the libraries (libpv, libwebcore, libkjs) need to be built
	# with -mlong-calls. When built at -O0, those libraries are
	# too big for a thumb "BL <label>" to go from one end to the other.

	## As hopefully a temporary hack,
	## use this to force a full ARM build (for easier debugging in gdb)
	## (don't forget to do a clean build)
	##TARGET_arm_release_CFLAGS := $(TARGET_arm_release_CFLAGS) -fno-omit-frame-pointer
	##TARGET_thumb_release_CFLAGS := $(TARGET_thumb_release_CFLAGS) -marm -fno-omit-frame-pointer

	android_config_h := $(call select-android-config-h,linux-arm)
	arch_include_dir := $(dir $(android_config_h))

	$(combo_target)GLOBAL_CFLAGS += \
	-msoft-float -fpic \
	-ffunction-sections \
	-funwind-tables \
	-fstack-protector \
	-fno-short-enums \
	$(arch_version_cflags) \
	-include $(android_config_h) \
	-I $(arch_include_dir)

	# We only need thumb interworking in cases where thumb support
	# is available in the architecture, and just to be sure, (and
	# since sometimes thumb-interwork appears to be default), we
	# specifically disable when thumb support is unavailable.
	ifeq ($(ARCH_ARM_HAVE_THUMB_SUPPORT),true)
	$(combo_target)GLOBAL_CFLAGS += -mthumb-interwork
	else
	$(combo_target)GLOBAL_CFLAGS += -mno-thumb-interwork
	endif

	$(combo_target)GLOBAL_CPPFLAGS += -fvisibility-inlines-hidden

	$(combo_target)RELEASE_CFLAGS := \
	-DSK_RELEASE -DNDEBUG \
	-O2 -g \
	-Wstrict-aliasing=2 \
	-finline-functions \
	-fno-inline-functions-called-once \
	-fgcse-after-reload \
	-frerun-cse-after-loop \
	-frename-registers

	libc_root := bionic/libc
	libm_root := bionic/libm
	libstdc++_root := bionic/libstdc++
	libthread_db_root := bionic/libthread_db


	## on some hosts, the target cross-compiler is not available so do not run this command
	ifneq ($(wildcard $($(combo_target)CC)),)
	# We compile with the global cflags to ensure that
	# any flags which affect libgcc are correctly taken
	# into account.
	$(combo_target)LIBGCC := $(shell $($(combo_target)CC) $($(combo_target)GLOBAL_CFLAGS) -print-libgcc-file-name)
	endif

	# unless CUSTOM_KERNEL_HEADERS is defined, we're going to use
	# symlinks located in out/ to point to the appropriate kernel
	# headers. see 'config/kernel_headers.make' for more details
	#
	ifneq ($(CUSTOM_KERNEL_HEADERS),)
	KERNEL_HEADERS_COMMON := $(CUSTOM_KERNEL_HEADERS)
	KERNEL_HEADERS_ARCH := $(CUSTOM_KERNEL_HEADERS)
	else
	KERNEL_HEADERS_COMMON := $(libc_root)/kernel/common
	KERNEL_HEADERS_ARCH := $(libc_root)/kernel/arch-$(TARGET_ARCH)
	endif
	KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)

	$(combo_target)C_INCLUDES := \
	$(libc_root)/arch-arm/include \
	$(libc_root)/include \
	$(libstdc++_root)/include \
	$(KERNEL_HEADERS) \
	$(libm_root)/include \
	$(libm_root)/include/arch/arm \
	$(libthread_db_root)/include

	TARGET_CRTBEGIN_STATIC_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_static.o
	TARGET_CRTBEGIN_DYNAMIC_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtbegin_dynamic.o
	TARGET_CRTEND_O := $(TARGET_OUT_STATIC_LIBRARIES)/crtend_android.o

	TARGET_STRIP_MODULE:=true

	$(combo_target)DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm

	$(combo_target)CUSTOM_LD_COMMAND := true
	define transform-o-to-shared-lib-inner
	$(TARGET_CXX) \
	-nostdlib -Wl,-soname,$(notdir $@) -Wl,-T,$(BUILD_SYSTEM)/armelf.xsc \
	-Wl,--gc-sections \
	-Wl,-shared,-Bsymbolic \
	$(TARGET_GLOBAL_LD_DIRS) \
	$(PRIVATE_ALL_OBJECTS) \
	-Wl,--whole-archive \
	$(call normalize-host-libraries,$(PRIVATE_ALL_WHOLE_STATIC_LIBRARIES)) \
	-Wl,--no-whole-archive \
	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
	$(call normalize-target-libraries,$(PRIVATE_ALL_SHARED_LIBRARIES)) \
	-o $@ \
	$(PRIVATE_LDFLAGS) \
	$(TARGET_LIBGCC)
	endef

	define transform-o-to-executable-inner
	$(TARGET_CXX) -nostdlib -Bdynamic -Wl,-T,$(BUILD_SYSTEM)/armelf.x \
	-Wl,-dynamic-linker,/system/bin/linker \
	-Wl,--gc-sections \
	-Wl,-z,nocopyreloc \
	-o $@ \
	$(TARGET_GLOBAL_LD_DIRS) \
	-Wl,-rpath-link=$(TARGET_OUT_INTERMEDIATE_LIBRARIES) \
	$(call normalize-target-libraries,$(PRIVATE_ALL_SHARED_LIBRARIES)) \
	$(TARGET_CRTBEGIN_DYNAMIC_O) \
	$(PRIVATE_ALL_OBJECTS) \
	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
	$(PRIVATE_LDFLAGS) \
	$(TARGET_LIBGCC) \
	$(TARGET_CRTEND_O)
	endef

	define transform-o-to-static-executable-inner
	$(TARGET_CXX) -nostdlib -Bstatic -Wl,-T,$(BUILD_SYSTEM)/armelf.x \
	-Wl,--gc-sections \
	-o $@ \
	$(TARGET_GLOBAL_LD_DIRS) \
	$(TARGET_CRTBEGIN_STATIC_O) \
	$(PRIVATE_LDFLAGS) \
	$(PRIVATE_ALL_OBJECTS) \
	$(call normalize-target-libraries,$(PRIVATE_ALL_STATIC_LIBRARIES)) \
	$(TARGET_LIBGCC) \
	$(TARGET_CRTEND_O)
	endef