code.delx.au - pulseaudio/blob - m4/ax_check_flag.m4

   1 # ===========================================================================
   2 #       http://www.gnu.org/software/autoconf-archive/ax_check_flag.html
   3 # ===========================================================================
   4 #
   5 # SYNOPSIS
   6 #
   7 #   AX_CHECK_PREPROC_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
   8 #   AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
   9 #   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS])
  10 #   AX_APPEND_FLAG(FLAG, [FLAGS-VARIABLE])
  11 #   AX_APPEND_COMPILE_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS])
  12 #   AX_APPEND_LINK_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS])
  13 #
  14 # DESCRIPTION
  15 #
  16 #   Check whether the given FLAG works with the current language's
  17 #   preprocessor/compiler/linker, or whether they give an error. (Warnings,
  18 #   however, are ignored.)
  19 #
  20 #   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
  21 #   success/failure.
  22 #
  23 #   If EXTRA-FLAGS is defined, it is added to the current language's default
  24 #   flags (e.g.  CFLAGS) when the check is done.  The check us thus made
  25 #   with the following flags: "CFLAGS EXTRA-FLAGS FLAG".  EXTRA-FLAGS can
  26 #   for example be used to force the compiler to issue an error when a bad
  27 #   flag is given.
  28 #
  29 #   AX_APPEND_FLAG appends the FLAG to the FLAG-VARIABLE shell variable or
  30 #   the current language's flags if not specified.  FLAG is not added to
  31 #   FLAG-VARIABLE if it is already in the shell variable.
  32 #
  33 #   AX_APPEND_COMPILE_FLAGS checks for each FLAG1, FLAG2, etc. using
  34 #   AX_CHECK_COMPILE_FLAG and if the check is successful the flag is added
  35 #   to the appropriate FLAGS variable with AX_APPEND_FLAG.  The
  36 #   FLAGS-VARIABLE and EXTRA-FLAGS arguments are the same as in the other
  37 #   macros. AX_APPEND_LINK_FLAGS does the same for linker flags.
  38 #
  39 #   NOTE: Based on AX_CHECK_COMPILER_FLAGS and AX_CFLAGS_GCC_OPTION.
  40 #
  41 # LICENSE
  42 #
  43 #   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
  44 #   Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>
  45 #   Copyright (c) 2009 Matteo Frigo
  46 #   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
  47 #
  48 #   This program is free software: you can redistribute it and/or modify it
  49 #   under the terms of the GNU General Public License as published by the
  50 #   Free Software Foundation, either version 3 of the License, or (at your
  51 #   option) any later version.
  52 #
  53 #   This program is distributed in the hope that it will be useful, but
  54 #   WITHOUT ANY WARRANTY; without even the implied warranty of
  55 #   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  56 #   Public License for more details.
  57 #
  58 #   You should have received a copy of the GNU General Public License along
  59 #   with this program. If not, see <http://www.gnu.org/licenses/>.
  60 #
  61 #   As a special exception, the respective Autoconf Macro's copyright owner
  62 #   gives unlimited permission to copy, distribute and modify the configure
  63 #   scripts that are the output of Autoconf when processing the Macro. You
  64 #   need not follow the terms of the GNU General Public License when using
  65 #   or distributing such scripts, even though portions of the text of the
  66 #   Macro appear in them. The GNU General Public License (GPL) does govern
  67 #   all other use of the material that constitutes the Autoconf Macro.
  68 #
  69 #   This special exception to the GPL applies to versions of the Autoconf
  70 #   Macro released by the Autoconf Archive. When you make and distribute a
  71 #   modified version of the Autoconf Macro, you may extend this special
  72 #   exception to the GPL to apply to your modified version as well.
  73
  74 #serial 2
  75
  76 AC_DEFUN([AX_CHECK_PREPROC_FLAG],
  77 [AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
  78 AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]cppflags_$4_$1])dnl
  79 AC_CACHE_CHECK([whether _AC_LANG preprocessor accepts $1], CACHEVAR, [
  80   ax_check_save_flags=$CPPFLAGS
  81   CPPFLAGS="$CPPFLAGS $4 $1"
  82   AC_PREPROC_IFELSE([AC_LANG_PROGRAM()],
  83     [AS_VAR_SET([CACHEVAR],[yes])],
  84     [AS_VAR_SET([CACHEVAR],[no])])
  85   CPPFLAGS=$ax_check_save_flags])
  86 AS_VAR_IF([CACHEVAR], "yes",
  87   [m4_default([$2], :)],
  88   [m4_default([$3], :)])
  89 AS_VAR_POPDEF([CACHEVAR])dnl
  90 ])dnl AX_CHECK_PREPROC_FLAGS
  91
  92 AC_DEFUN([AX_CHECK_COMPILE_FLAG],
  93 [AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
  94 AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
  95 AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
  96   ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
  97   _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
  98   AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
  99     [AS_VAR_SET([CACHEVAR],[yes])],
 100     [AS_VAR_SET([CACHEVAR],[no])])
 101   _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
 102 AS_VAR_IF([CACHEVAR], "yes",
 103   [m4_default([$2], :)],
 104   [m4_default([$3], :)])
 105 AS_VAR_POPDEF([CACHEVAR])dnl
 106 ])dnl AX_CHECK_COMPILE_FLAGS
 107
 108 AC_DEFUN([AX_CHECK_LINK_FLAG],
 109 [AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
 110 AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
 111   ax_check_save_flags=$LDFLAGS
 112   LDFLAGS="$LDFLAGS $4 $1"
 113   AC_LINK_IFELSE([AC_LANG_PROGRAM()],
 114     [AS_VAR_SET([CACHEVAR],[yes])],
 115     [AS_VAR_SET([CACHEVAR],[no])])
 116   LDFLAGS=$ax_check_save_flags])
 117 AS_VAR_IF([CACHEVAR], "yes",
 118   [m4_default([$2], :)],
 119   [m4_default([$3], :)])
 120 AS_VAR_POPDEF([CACHEVAR])dnl
 121 ])dnl AX_CHECK_LINK_FLAGS
 122
 123
 124 AC_DEFUN([AX_APPEND_FLAG],
 125 [AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
 126 AC_REQUIRE([AC_PROG_GREP])
 127 AS_VAR_PUSHDEF([FLAGS], [m4_default($2,_AC_LANG_PREFIX[]FLAGS)])dnl
 128 AS_VAR_SET_IF([FLAGS],
 129   [AS_IF([AS_ECHO(" $[]FLAGS ") | $GREP " $1 " 2>&1 >/dev/null],
 130     [AC_RUN_LOG([: FLAGS already contains $1])],
 131     [AC_RUN_LOG([: FLAGS="$FLAGS $1"])
 132     AS_VAR_APPEND([FLAGS], [" $1"])])],
 133   [AS_VAR_SET([FLAGS],[$1])])
 134 AS_VAR_POPDEF([FLAGS])dnl
 135 ])dnl AX_APPEND_FLAG
 136
 137 AC_DEFUN([AX_APPEND_COMPILE_FLAGS],
 138 [for flag in $1; do
 139   AX_CHECK_COMPILE_FLAG([$flag], [AX_APPEND_FLAG([$flag], [$2])], [], [$3])
 140 done
 141 ])dnl AX_APPEND_COMPILE_FLAGS
 142
 143 AC_DEFUN([AX_APPEND_LINK_FLAGS],
 144 [for flag in $1; do
 145   AX_CHECK_LINK_FLAG([$flag], [AX_APPEND_FLAG([$flag], [m4_default([$2], [LDFLAGS])])], [], [$3])
 146 done
 147 ])dnl AX_APPEND_LINK_FLAGS