1# SPDX-License-Identifier: GPL-2.0-only 2# Kconfig helper macros 3 4# Convenient variables 5comma := , 6quote := " 7squote := ' 8empty := 9space := $(empty) $(empty) 10dollar := $ 11right_paren := ) 12left_paren := ( 13 14# $(if-success,<command>,<then>,<else>) 15# Return <then> if <command> exits with 0, <else> otherwise. 16if-success = $(shell,{ $(1); } >/dev/null 2>&1 && echo "$(2)" || echo "$(3)") 17 18# $(success,<command>) 19# Return y if <command> exits with 0, n otherwise 20success = $(if-success,$(1),y,n) 21 22# $(failure,<command>) 23# Return n if <command> exits with 0, y otherwise 24failure = $(if-success,$(1),n,y) 25 26# $(cc-option,<flag>) 27# Return y if the compiler supports <flag>, n otherwise 28cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -S -x c /dev/null -o /dev/null) 29 30# $(ld-option,<flag>) 31# Return y if the linker supports <flag>, n otherwise 32ld-option = $(success,$(LD) -v $(1)) 33 34# $(as-instr,<instr>) 35# Return y if the assembler supports <instr>, n otherwise 36as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -) 37 38# check if $(CC) and $(LD) exist 39$(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found) 40$(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) 41 42# Fail if the linker is gold as it's not capable of linking the kernel proper 43$(error-if,$(success, $(LD) -v | grep -q gold), gold linker '$(LD)' not supported) 44 45# gcc version including patch level 46gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) 47 48# machine bit flags 49# $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise. 50# $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise. 51cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$(1)) 52m32-flag := $(cc-option-bit,-m32) 53m64-flag := $(cc-option-bit,-m64) 54