From: WANG Xuerui <git@xxxxxxxxxx> Now the arch code is mostly ready for LLVM/Clang consumption, it is time to re-organize the CFLAGS a little to actually enable the LLVM build. In particular, -mexplicit-relocs and -mdirect-extern-access are not necessary nor supported on Clang; feature detection via cc-option would not work, because that way the broken combo of "new GNU as + old GCC" would seem to get "fixed", but actually produce broken kernels. Explicitly depending on CONFIG_CC_IS_CLANG is thus necessary to not regress UX for those building their own kernels. A build with !RELOCATABLE && !MODULE is confirmed working within a QEMU environment; support for the two features are currently blocked on LLVM/Clang, and will come later. Signed-off-by: WANG Xuerui <git@xxxxxxxxxx> --- arch/loongarch/Makefile | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile index 366771016b99..82c619791a63 100644 --- a/arch/loongarch/Makefile +++ b/arch/loongarch/Makefile @@ -51,7 +51,9 @@ LDFLAGS_vmlinux += -static -n -nostdlib # When the assembler supports explicit relocation hint, we must use it. # GCC may have -mexplicit-relocs off by default if it was built with an old -# assembler, so we force it via an option. +# assembler, so we force it via an option. For LLVM/Clang the desired behavior +# is the default, and the flag is not supported, so don't pass it if Clang is +# being used. # # When the assembler does not supports explicit relocation hint, we can't use # it. Disable it if the compiler supports it. @@ -61,8 +63,10 @@ LDFLAGS_vmlinux += -static -n -nostdlib # combination of a "new" assembler and "old" compiler is not supported. Either # upgrade the compiler or downgrade the assembler. ifdef CONFIG_AS_HAS_EXPLICIT_RELOCS +ifndef CONFIG_CC_IS_CLANG cflags-y += -mexplicit-relocs KBUILD_CFLAGS_KERNEL += -mdirect-extern-access +endif else cflags-y += $(call cc-option,-mno-explicit-relocs) KBUILD_AFLAGS_KERNEL += -Wa,-mla-global-with-pcrel -- 2.40.0
