m4/ax_append_compile_flags.m4

   1 # SPDX-License-Identifier: FSFAP
   2 # ============================================================================
   3 #  https://www.gnu.org/software/autoconf-archive/ax_append_compile_flags.html
   4 # ============================================================================
   5 #
   6 # SYNOPSIS
   7 #
   8 #   AX_APPEND_COMPILE_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS], [INPUT])
   9 #
  10 # DESCRIPTION
  11 #
  12 #   For every FLAG1, FLAG2 it is checked whether the compiler works with the
  13 #   flag.  If it does, the flag is added FLAGS-VARIABLE
  14 #
  15 #   If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
  16 #   CFLAGS) is used.  During the check the flag is always added to the
  17 #   current language's flags.
  18 #
  19 #   If EXTRA-FLAGS is defined, it is added to the current language's default
  20 #   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
  21 #   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
  22 #   force the compiler to issue an error when a bad flag is given.
  23 #
  24 #   INPUT gives an alternative input source to AC_COMPILE_IFELSE.
  25 #
  26 #   NOTE: This macro depends on the AX_APPEND_FLAG and
  27 #   AX_CHECK_COMPILE_FLAG. Please keep this macro in sync with
  28 #   AX_APPEND_LINK_FLAGS.
  29 #
  30 # LICENSE
  31 #
  32 #   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
  33 #
  34 #   Copying and distribution of this file, with or without modification, are
  35 #   permitted in any medium without royalty provided the copyright notice
  36 #   and this notice are preserved.  This file is offered as-is, without any
  37 #   warranty.
  38
  39 #serial 7
  40
  41 AC_DEFUN([AX_APPEND_COMPILE_FLAGS],
  42 [AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
  43 AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
  44 for flag in $1; do
  45   AX_CHECK_COMPILE_FLAG([$flag], [AX_APPEND_FLAG([$flag], [$2])], [], [$3], [$4])
  46 done
  47 ])dnl AX_APPEND_COMPILE_FLAGS