1 # SPDX-License-Identifier: GPL-2.0-only 2 # Kconfig helper macros 3 4 # Convenient variables 5 comma := , 6 quote := " 7 squote := ' 8 empty := 9 space := $(empty) $(empty) 10 dollar := $ 11 right_paren := ) 12 left_paren := ( 13 14 # $(if-success,<command>,<then>,<else>) 15 # Return <then> if <command> exits with 0, <else> otherwise. 16 if-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 20 success = $(if-success,$(1),y,n) 21 22 # $(failure,<command>) 23 # Return n if <command> exits with 0, y otherwise 24 failure = $(if-success,$(1),n,y) 25 26 # $(cc-option,<flag>) 27 # Return y if the compiler supports <flag>, n otherwise 28 cc-option = $(success,mkdir .tmp_$$$$; trap "rm -rf .tmp_$$$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$$$/tmp.o) 29 30 # $(ld-option,<flag>) 31 # Return y if the linker supports <flag>, n otherwise 32 ld-option = $(success,$(LD) -v $(1)) 33 34 # $(as-instr,<instr>) 35 # Return y if the assembler supports <instr>, n otherwise 36 as-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 # machine bit flags 46 # $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise. 47 # $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise. 48 cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$(1)) 49 m32-flag := $(cc-option-bit,-m32) 50 m64-flag := $(cc-option-bit,-m64) 51