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Diffstat (limited to 'm4/ax_check_link_flag.m4')
| -rw-r--r-- | m4/ax_check_link_flag.m4 | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/m4/ax_check_link_flag.m4 b/m4/ax_check_link_flag.m4 new file mode 100644 index 0000000..819409a --- /dev/null +++ b/m4/ax_check_link_flag.m4 @@ -0,0 +1,74 @@ +# =========================================================================== +# https://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT]) +# +# DESCRIPTION +# +# Check whether the given FLAG works with the linker 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 linker's default flags +# when the check is done. The check is thus made with the flags: "LDFLAGS +# EXTRA-FLAGS FLAG". This can for example be used to force the linker to +# issue an error when a bad flag is given. +# +# INPUT gives an alternative input source to AC_LINK_IFELSE. +# +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this +# macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG. +# +# LICENSE +# +# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de> +# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com> +# +# This program is free software: you can redistribute it and/or modify it +# under the terms of the GNU General Public License as published by the +# Free Software Foundation, either version 3 of the License, or (at your +# option) any later version. +# +# This program is distributed in the hope that it will be useful, but +# WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General +# Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program. If not, see <https://www.gnu.org/licenses/>. +# +# As a special exception, the respective Autoconf Macro's copyright owner +# gives unlimited permission to copy, distribute and modify the configure +# scripts that are the output of Autoconf when processing the Macro. You +# need not follow the terms of the GNU General Public License when using +# or distributing such scripts, even though portions of the text of the +# Macro appear in them. The GNU General Public License (GPL) does govern +# all other use of the material that constitutes the Autoconf Macro. +# +# This special exception to the GPL applies to versions of the Autoconf +# Macro released by the Autoconf Archive. When you make and distribute a +# modified version of the Autoconf Macro, you may extend this special +# exception to the GPL to apply to your modified version as well. + +#serial 5 + +AC_DEFUN([AX_CHECK_LINK_FLAG], +[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl +AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [ + ax_check_save_flags=$LDFLAGS + LDFLAGS="$LDFLAGS $4 $1" + AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], + [AS_VAR_SET(CACHEVAR,[yes])], + [AS_VAR_SET(CACHEVAR,[no])]) + LDFLAGS=$ax_check_save_flags]) +AS_VAR_IF(CACHEVAR,yes, + [m4_default([$2], :)], + [m4_default([$3], :)]) +AS_VAR_POPDEF([CACHEVAR])dnl +])dnl AX_CHECK_LINK_FLAGS |