Similar to 'cc-option' or 'ld-option', it is occasionally necessary to check whether the assembler supports certain ISA extensions. In the arm64 code we currently do this in Makefile with an additional define: lseinstr := $(call as-instr,.arch_extension lse,-DCONFIG_AS_LSE=1) Add the 'as-instr' option so that it can be used in Kconfig directly: def_bool $(as-instr,.arch_extension lse) Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Cc: linux-kbuild@xxxxxxxxxxxxxxx Reviewed-by: Vladimir Murzin <vladimir.murzin@xxxxxxx> Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> --- scripts/Kconfig.include | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index d4adfbe42690..9d07e59cbdf7 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -31,6 +31,10 @@ cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -E -x c /dev/null -o /de # Return y if the linker supports <flag>, n otherwise ld-option = $(success,$(LD) -v $(1)) +# $(as-instr,<instr>) +# Return y if the assembler supports <instr>, n otherwise +as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -) + # check if $(CC) and $(LD) exist $(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found) $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found)