ax_check_compile_flag.m4 3.3 KB

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  1. # ===========================================================================
  2. # https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
  3. # ===========================================================================
  4. #
  5. # SYNOPSIS
  6. #
  7. # AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
  8. #
  9. # DESCRIPTION
  10. #
  11. # Check whether the given FLAG works with the current language's compiler
  12. # or gives an error. (Warnings, however, are ignored)
  13. #
  14. # ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
  15. # success/failure.
  16. #
  17. # If EXTRA-FLAGS is defined, it is added to the current language's default
  18. # flags (e.g. CFLAGS) when the check is done. The check is thus made with
  19. # the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
  20. # force the compiler to issue an error when a bad flag is given.
  21. #
  22. # INPUT gives an alternative input source to AC_COMPILE_IFELSE.
  23. #
  24. # NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
  25. # macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
  26. #
  27. # LICENSE
  28. #
  29. # Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
  30. # Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
  31. #
  32. # This program is free software: you can redistribute it and/or modify it
  33. # under the terms of the GNU General Public License as published by the
  34. # Free Software Foundation, either version 3 of the License, or (at your
  35. # option) any later version.
  36. #
  37. # This program is distributed in the hope that it will be useful, but
  38. # WITHOUT ANY WARRANTY; without even the implied warranty of
  39. # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  40. # Public License for more details.
  41. #
  42. # You should have received a copy of the GNU General Public License along
  43. # with this program. If not, see <https://www.gnu.org/licenses/>.
  44. #
  45. # As a special exception, the respective Autoconf Macro's copyright owner
  46. # gives unlimited permission to copy, distribute and modify the configure
  47. # scripts that are the output of Autoconf when processing the Macro. You
  48. # need not follow the terms of the GNU General Public License when using
  49. # or distributing such scripts, even though portions of the text of the
  50. # Macro appear in them. The GNU General Public License (GPL) does govern
  51. # all other use of the material that constitutes the Autoconf Macro.
  52. #
  53. # This special exception to the GPL applies to versions of the Autoconf
  54. # Macro released by the Autoconf Archive. When you make and distribute a
  55. # modified version of the Autoconf Macro, you may extend this special
  56. # exception to the GPL to apply to your modified version as well.
  57. #serial 5
  58. AC_DEFUN([AX_CHECK_COMPILE_FLAG],
  59. [AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
  60. AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
  61. AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
  62. ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
  63. _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
  64. AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
  65. [AS_VAR_SET(CACHEVAR,[yes])],
  66. [AS_VAR_SET(CACHEVAR,[no])])
  67. _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
  68. AS_VAR_IF(CACHEVAR,yes,
  69. [m4_default([$2], :)],
  70. [m4_default([$3], :)])
  71. AS_VAR_POPDEF([CACHEVAR])dnl
  72. ])dnl AX_CHECK_COMPILE_FLAGS