linux/scripts/Makefile.clang
Nick Desaulniers f12b034afe scripts/Makefile.clang: default to LLVM_IAS=1
LLVM_IAS=1 controls enabling clang's integrated assembler via
-integrated-as. This was an explicit opt in until we could enable
assembler support in Clang for more architecures. Now we have support
and CI coverage of LLVM_IAS=1 for all architecures except a few more
bugs affecting s390 and powerpc.

This commit flips the default from opt in via LLVM_IAS=1 to opt out via
LLVM_IAS=0.  CI systems or developers that were previously doing builds
with CC=clang or LLVM=1 without explicitly setting LLVM_IAS must now
explicitly opt out via LLVM_IAS=0, otherwise they will be implicitly
opted-in.

This finally shortens the command line invocation when cross compiling
with LLVM to simply:

$ make ARCH=arm64 LLVM=1

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-08-10 09:13:25 +09:00

36 lines
1.3 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 := $(CLANG_TARGET_FLAGS_$(SRCARCH))
ifeq ($(CROSS_COMPILE),)
ifeq ($(CLANG_TARGET_FLAGS),)
$(error Specify CROSS_COMPILE or add '--target=' option to scripts/Makefile.clang)
else
CLANG_FLAGS += --target=$(CLANG_TARGET_FLAGS)
endif # CLANG_TARGET_FLAGS
else
CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
endif # CROSS_COMPILE
ifeq ($(LLVM_IAS),0)
CLANG_FLAGS += -no-integrated-as
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
else
CLANG_FLAGS += -integrated-as
endif
CLANG_FLAGS += -Werror=unknown-warning-option
KBUILD_CFLAGS += $(CLANG_FLAGS)
KBUILD_AFLAGS += $(CLANG_FLAGS)
export CLANG_FLAGS