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# 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)
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