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,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
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# 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.
48cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$(1))
49m32-flag := $(cc-option-bit,-m32)
50m64-flag := $(cc-option-bit,-m64)
51