| # SPDX-License-Identifier: GPL-2.0-only |
| # Kconfig helper macros |
| |
| # Convenient variables |
| comma := , |
| quote := " |
| squote := ' |
| empty := |
| space := $(empty) $(empty) |
| dollar := $ |
| right_paren := ) |
| left_paren := ( |
| |
| # $(if-success,<command>,<then>,<else>) |
| # Return <then> if <command> exits with 0, <else> otherwise. |
| if-success = $(shell,{ $(1); } >/dev/null 2>&1 && echo "$(2)" || echo "$(3)") |
| |
| # $(success,<command>) |
| # Return y if <command> exits with 0, n otherwise |
| success = $(if-success,$(1),y,n) |
| |
| # $(failure,<command>) |
| # Return n if <command> exits with 0, y otherwise |
| failure = $(if-success,$(1),n,y) |
| |
| # $(cc-option,<flag>) |
| # Return y if the compiler supports <flag>, n otherwise |
| cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -S -x c /dev/null -o /dev/null) |
| |
| # $(ld-option,<flag>) |
| # Return y if the linker supports <flag>, n otherwise |
| ld-option = $(success,$(LD) -v $(1)) |
| |
| # $(as-option,<flag>) |
| # /dev/zero is used as output instead of /dev/null as some assembler cribs when |
| # both input and output are same. Also both of them have same write behaviour so |
| # can be easily substituted. |
| as-option = $(success, $(CC) $(CLANG_FLAGS) $(1) -c -x assembler /dev/null -o /dev/zero) |
| |
| # $(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) |
| |
| # Fail if the linker is gold as it's not capable of linking the kernel proper |
| $(error-if,$(success, $(LD) -v | grep -q gold), gold linker '$(LD)' not supported) |
| |
| # machine bit flags |
| # $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise. |
| # $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise. |
| cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$(1)) |
| m32-flag := $(cc-option-bit,-m32) |
| m64-flag := $(cc-option-bit,-m64) |
