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Diffstat (limited to 'm4/ax_check_preproc_flag.m4')
| -rw-r--r-- | m4/ax_check_preproc_flag.m4 | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/m4/ax_check_preproc_flag.m4 b/m4/ax_check_preproc_flag.m4 new file mode 100644 index 0000000..ee0ccb6 --- /dev/null +++ b/m4/ax_check_preproc_flag.m4 @@ -0,0 +1,55 @@ +# SPDX-License-Identifier: FSFAP +# +# =========================================================================== +# https://www.gnu.org/software/autoconf-archive/ax_check_preproc_flag.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_PREPROC_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT]) +# +# DESCRIPTION +# +# Check whether the given FLAG works with the current language's +# preprocessor or gives an error. (Warnings, however, are ignored) +# +# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on +# success/failure. +# +# If EXTRA-FLAGS is defined, it is added to the preprocessor's default +# flags when the check is done. The check is thus made with the flags: +# "CPPFLAGS EXTRA-FLAGS FLAG". This can for example be used to force the +# preprocessor to issue an error when a bad flag is given. +# +# INPUT gives an alternative input source to AC_PREPROC_IFELSE. +# +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this +# macro in sync with AX_CHECK_{COMPILE,LINK}_FLAG. +# +# LICENSE +# +# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de> +# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com> +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. This file is offered as-is, without any +# warranty. + +#serial 6 + +AC_DEFUN([AX_CHECK_PREPROC_FLAG], +[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]cppflags_$4_$1])dnl +AC_CACHE_CHECK([whether _AC_LANG preprocessor accepts $1], CACHEVAR, [ + ax_check_save_flags=$CPPFLAGS + CPPFLAGS="$CPPFLAGS $4 $1" + AC_PREPROC_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], + [AS_VAR_SET(CACHEVAR,[yes])], + [AS_VAR_SET(CACHEVAR,[no])]) + CPPFLAGS=$ax_check_save_flags]) +AS_VAR_IF(CACHEVAR,yes, + [m4_default([$2], :)], + [m4_default([$3], :)]) +AS_VAR_POPDEF([CACHEVAR])dnl +])dnl AX_CHECK_PREPROC_FLAGS |