scripts/Kconfig.include

   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)