mainline inclusion from mainline-v6.12-rc1 commit a7e0837724562ea8c1d869dd1a5cb1119ef651c3 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IB3IRE Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... --------------------------------------------------------------------------- When building kernel with "make CC=clang defconfig", LLVM Assembler is used due to LLVM_IAS=0 is not specified, then AS_HAS_THIN_ADD_SUB is not set, thus objtool can not be built after enable it for Clang. config AS_HAS_THIN_ADD_SUB is to check whether -mthin-add-sub option is available to know R_LARCH_{32,64}_PCREL are supported for GNU Assembler, there is no such an option for LLVM Assembler. The minimal version of Clang is 18 for building LoongArch kernel, and Clang >= 17 has already supported R_LARCH_{32,64}_PCREL, that is to say, there is no need to depend on AS_HAS_THIN_ADD_SUB for Clang, so just set AS_HAS_THIN_ADD_SUB as y if AS_IS_LLVM. Fixes: 120dd4118e58 ("LoongArch: Only allow OBJTOOL & ORC unwinder if toolchain supports -mthin-add-sub") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> --- arch/loongarch/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 695f584c4595..f906d66cbac4 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -267,7 +267,7 @@ config AS_HAS_FCSR_CLASS def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0) config AS_HAS_THIN_ADD_SUB - def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) + def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) || AS_IS_LLVM config AS_HAS_LSX_EXTENSION def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0) -- 2.42.0