# SPDX-License-Identifier: GPL-2.0-only# Kconfig helper macros # Convenient variablescomma       := ,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 otherwisesuccess = $(if-success,$(1),y,n) # $(failure,<command>)# Return n if <command> exits with 0, y otherwisefailure = $(if-success,$(1),n,y) # $(cc-option,<flag>)# Return y if the compiler supports <flag>, n otherwisecc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$/tmp.o) # $(ld-option,<flag>)# Return y if the linker supports <flag>, n otherwiseld-option = $(success,$(LD) -v $(1)) # $(as-instr,<instr>)# Return y if the assembler supports <instr>, n otherwiseas-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) $(2) -Wa$(comma)--fatal-warnings -c -x assembler-with-cpp -o /dev/null -)as-instr64 = $(as-instr,$(1),$(m64-flag)) # check if $(CC) and $(LD) exist$(error-if,$(failure,command -v $(CC)),C compiler '$(CC)' not found)$(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) # Get the C compiler name, version, and error out if it is not supported.cc-info := $(shell,$(srctree)/scripts/cc-version.sh $(CC))$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this C compiler is not supported.)cc-name := $(shell,set -- $(cc-info) && echo $1)cc-version := $(shell,set -- $(cc-info) && echo $2) # Get the assembler name, version, and error out if it is not supported.as-info := $(shell,$(srctree)/scripts/as-version.sh $(CC) $(CLANG_FLAGS))$(error-if,$(success,test -z "$(as-info)"),Sorry$(comma) this assembler is not supported.)as-name := $(shell,set -- $(as-info) && echo $1)as-version := $(shell,set -- $(as-info) && echo $2) # Get the linker name, version, and error out if it is not supported.ld-info := $(shell,$(srctree)/scripts/ld-version.sh $(LD))$(error-if,$(success,test -z "$(ld-info)"),Sorry$(comma) this linker is not supported.)ld-name := $(shell,set -- $(ld-info) && echo $1)ld-version := $(shell,set -- $(ld-info) && echo $2) # 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) # Test whether the compiler can link userspace applicationscc_can_link_user = $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(1)) rustc-version := $(shell,$(srctree)/scripts/rustc-version.sh $(RUSTC))rustc-llvm-version := $(shell,$(srctree)/scripts/rustc-llvm-version.sh $(RUSTC)) # $(rustc-option,<flag>)# Return y if the Rust compiler supports <flag>, n otherwise# Calls to this should be guarded so that they are not evaluated if# CONFIG_RUST_IS_AVAILABLE is not set.# If you are testing for unstable features, consider testing RUSTC_VERSION# instead, as features may have different completeness while available.rustc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(RUSTC) $(1) --crate-type=rlib /dev/null --out-dir=.tmp_$$ -o .tmp_$$/tmp.rlib)