mirror of
https://github.com/torvalds/linux.git
synced 2024-12-27 13:22:23 +00:00
feb843a469
When preprocessing arch/*/kernel/vmlinux.lds.S, the target triple is
not passed to $(CPP) because we add it only to KBUILD_{C,A}FLAGS.
As a result, the linker script is preprocessed with predefined macros
for the build host instead of the target.
Assuming you use an x86 build machine, compare the following:
$ clang -dM -E -x c /dev/null
$ clang -dM -E -x c /dev/null -target aarch64-linux-gnu
There is no actual problem presumably because our linker scripts do not
rely on such predefined macros, but it is better to define correct ones.
Move $(CLANG_FLAGS) to KBUILD_CPPFLAGS, so that all *.c, *.S, *.lds.S
will be processed with the proper target triple.
[Note]
After the patch submission, we got an actual problem that needs this
commit. (CBL issue 1859)
Link: https://github.com/ClangBuiltLinux/linux/issues/1859
Reported-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
39 lines
1.6 KiB
Makefile
39 lines
1.6 KiB
Makefile
# Individual arch/{arch}/Makefiles should use -EL/-EB to set intended
|
|
# endianness and -m32/-m64 to set word size based on Kconfigs instead of
|
|
# relying on the target triple.
|
|
CLANG_TARGET_FLAGS_arm := arm-linux-gnueabi
|
|
CLANG_TARGET_FLAGS_arm64 := aarch64-linux-gnu
|
|
CLANG_TARGET_FLAGS_hexagon := hexagon-linux-musl
|
|
CLANG_TARGET_FLAGS_m68k := m68k-linux-gnu
|
|
CLANG_TARGET_FLAGS_mips := mipsel-linux-gnu
|
|
CLANG_TARGET_FLAGS_powerpc := powerpc64le-linux-gnu
|
|
CLANG_TARGET_FLAGS_riscv := riscv64-linux-gnu
|
|
CLANG_TARGET_FLAGS_s390 := s390x-linux-gnu
|
|
CLANG_TARGET_FLAGS_x86 := x86_64-linux-gnu
|
|
CLANG_TARGET_FLAGS_um := $(CLANG_TARGET_FLAGS_$(SUBARCH))
|
|
CLANG_TARGET_FLAGS := $(CLANG_TARGET_FLAGS_$(SRCARCH))
|
|
|
|
ifeq ($(CLANG_TARGET_FLAGS),)
|
|
$(error add '--target=' option to scripts/Makefile.clang)
|
|
else
|
|
CLANG_FLAGS += --target=$(CLANG_TARGET_FLAGS)
|
|
endif
|
|
|
|
ifeq ($(LLVM_IAS),0)
|
|
CLANG_FLAGS += -fno-integrated-as
|
|
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
|
|
CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
|
|
else
|
|
CLANG_FLAGS += -fintegrated-as
|
|
endif
|
|
# By default, clang only warns when it encounters an unknown warning flag or
|
|
# certain optimization flags it knows it has not implemented.
|
|
# Make it behave more like gcc by erroring when these flags are encountered
|
|
# so they can be implemented or wrapped in cc-option.
|
|
CLANG_FLAGS += -Werror=unknown-warning-option
|
|
CLANG_FLAGS += -Werror=ignored-optimization-argument
|
|
CLANG_FLAGS += -Werror=option-ignored
|
|
CLANG_FLAGS += -Werror=unused-command-line-argument
|
|
KBUILD_CPPFLAGS += $(CLANG_FLAGS)
|
|
export CLANG_FLAGS
|