1# The following definitions are the defaults used by all toolchains. 2# This is included in setup-toolchain.mk just before the inclusion 3# of the toolchain's specific setup.mk file which can then override 4# these definitions. 5# 6 7# These flags are used to ensure that a binary doesn't reference undefined 8# flags. 9TARGET_NO_UNDEFINED_LDFLAGS := -Wl,--no-undefined 10 11 12# Return the list of object, static libraries and shared libraries as they 13# must appear on the final static linker command (order is important). 14# 15# This can be over-ridden by a specific toolchain. Note that by default 16# we always put libgcc _after_ all static libraries and _before_ shared 17# libraries. This ensures that any libgcc function used by the final 18# executable will be copied into it. Otherwise, it could contain 19# symbol references to the same symbols as exported by shared libraries 20# and this causes binary compatibility problems when they come from 21# system libraries (e.g. libc.so and others). 22# 23# IMPORTANT: The result must use the host path convention. 24# 25# $1: object files 26# $2: static libraries 27# $3: whole static libraries 28# $4: shared libraries 29# 30TARGET-get-linker-objects-and-libraries = \ 31 $(call host-path, $1) \ 32 $(call link-whole-archives,$3) \ 33 $(call host-path, $2 $(PRIVATE_LIBGCC) $4) \ 34 35 36# These flags are used to enforce the NX (no execute) security feature in the 37# generated machine code. This adds a special section to the generated shared 38# libraries that instruct the Linux kernel to disable code execution from 39# the stack and the heap. 40TARGET_NO_EXECUTE_CFLAGS := -Wa,--noexecstack 41TARGET_NO_EXECUTE_LDFLAGS := -Wl,-z,noexecstack 42 43# These flags disable the above security feature 44TARGET_DISABLE_NO_EXECUTE_CFLAGS := -Wa,--execstack 45TARGET_DISABLE_NO_EXECUTE_LDFLAGS := -Wl,-z,execstack 46 47# These flags are used to mark certain regions of the resulting 48# executable or shared library as being read-only after the dynamic 49# linker has run. This makes GOT overwrite security attacks harder to 50# exploit. 51TARGET_RELRO_LDFLAGS := -Wl,-z,relro -Wl,-z,now 52 53# These flags disable the above security feature 54TARGET_DISABLE_RELRO_LDFLAGS := -Wl,-z,norelro -Wl,-z,lazy 55 56# This flag are used to provide compiler protection against format 57# string vulnerabilities. 58TARGET_FORMAT_STRING_CFLAGS := -Wformat -Werror=format-security 59 60# This flag disables the above security checks 61TARGET_DISABLE_FORMAT_STRING_CFLAGS := -Wno-error=format-security 62 63# NOTE: Ensure that TARGET_LIBGCC is placed after all private objects 64# and static libraries, but before any other library in the link 65# command line when generating shared libraries and executables. 66# 67# This ensures that all libgcc.a functions required by the target 68# will be included into it, instead of relying on what's available 69# on other libraries like libc.so, which may change between system 70# releases due to toolchain or library changes. 71# 72define cmd-build-shared-library 73$(PRIVATE_CXX) \ 74 -Wl,-soname,$(notdir $(LOCAL_BUILT_MODULE)) \ 75 -shared \ 76 --sysroot=$(call host-path,$(PRIVATE_SYSROOT_LINK)) \ 77 $(PRIVATE_LINKER_OBJECTS_AND_LIBRARIES) \ 78 $(PRIVATE_LDFLAGS) \ 79 $(PRIVATE_LDLIBS) \ 80 -o $(call host-path,$(LOCAL_BUILT_MODULE)) 81endef 82 83# The following -rpath-link= are needed for ld.bfd (default for MIPS) when 84# linking executable to supress warning about missing symbol by *so not directly needed. 85# ld.gold (default for ARM and X86) and ld.mcld don't emulate this buggy behavior, 86# and ignore -rpath-link completely. 87define cmd-build-executable 88$(PRIVATE_CXX) \ 89 -Wl,--gc-sections \ 90 -Wl,-z,nocopyreloc \ 91 --sysroot=$(call host-path,$(PRIVATE_SYSROOT_LINK)) \ 92 -Wl,-rpath-link=$(call host-path,$(PRIVATE_SYSROOT_LINK)/usr/lib) \ 93 -Wl,-rpath-link=$(call host-path,$(TARGET_OUT)) \ 94 $(PRIVATE_LINKER_OBJECTS_AND_LIBRARIES) \ 95 $(PRIVATE_LDFLAGS) \ 96 $(PRIVATE_LDLIBS) \ 97 -o $(call host-path,$(LOCAL_BUILT_MODULE)) 98endef 99 100define cmd-build-static-library 101$(PRIVATE_AR) $(call host-path,$(LOCAL_BUILT_MODULE)) $(PRIVATE_AR_OBJECTS) 102endef 103 104# The strip command is only used for shared libraries and executables. 105# It is thus safe to use --strip-unneeded, which is only dangerous 106# when applied to static libraries or object files. 107cmd-strip = $(PRIVATE_STRIP) --strip-unneeded $(call host-path,$1) 108 109# The command objcopy --add-gnu-debuglink= will be needed for Valgrind 110cmd-add-gnu-debuglink = $(PRIVATE_OBJCOPY) --add-gnu-debuglink=$(strip $(call host-path,$2)) $(call host-path,$1) 111 112TARGET_LIBGCC = -lgcc 113TARGET_LDLIBS := -lc -lm 114 115# 116# IMPORTANT: The following definitions must use lazy assignment because 117# the value of TOOLCHAIN_PREFIX or TARGET_CFLAGS can be changed later by 118# the toolchain's setup.mk script. 119# 120 121ifneq ($(findstring ccc-analyzer,$(CC)),) 122TARGET_CC = $(CC) 123else 124TARGET_CC = $(TOOLCHAIN_PREFIX)gcc 125endif 126TARGET_CFLAGS = 127TARGET_CONLYFLAGS = 128 129ifneq ($(findstring c++-analyzer,$(CXX)),) 130TARGET_CXX = $(CXX) 131else 132TARGET_CXX = $(TOOLCHAIN_PREFIX)g++ 133endif 134TARGET_CXXFLAGS = $(TARGET_CFLAGS) -fno-exceptions -fno-rtti 135 136TARGET_RS_CC = $(RENDERSCRIPT_TOOLCHAIN_PREFIX)llvm-rs-cc 137TARGET_RS_BCC = $(RENDERSCRIPT_TOOLCHAIN_PREFIX)bcc_compat 138TARGET_RS_FLAGS = -Wall -Werror 139 140TARGET_ASM = $(HOST_PREBUILT)/yasm 141TARGET_ASMFLAGS = 142 143TARGET_LD = $(TOOLCHAIN_PREFIX)ld 144TARGET_LDFLAGS := 145 146TARGET_AR = $(TOOLCHAIN_PREFIX)ar 147TARGET_ARFLAGS := crsD 148 149TARGET_STRIP = $(TOOLCHAIN_PREFIX)strip 150 151TARGET_OBJCOPY = $(TOOLCHAIN_PREFIX)objcopy 152 153TARGET_OBJ_EXTENSION := .o 154TARGET_LIB_EXTENSION := .a 155TARGET_SONAME_EXTENSION := .so 156