/usr/share/aclocal/ax_openmp.m4 is in autoconf-archive 20131101-1.
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# http://www.gnu.org/software/autoconf-archive/ax_openmp.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_OPENMP([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
#
# DESCRIPTION
#
# This macro tries to find out how to compile programs that use OpenMP a
# standard API and set of compiler directives for parallel programming
# (see http://www-unix.mcs/)
#
# On success, it sets the OPENMP_CFLAGS/OPENMP_CXXFLAGS/OPENMP_F77FLAGS
# output variable to the flag (e.g. -omp) used both to compile *and* link
# OpenMP programs in the current language.
#
# NOTE: You are assumed to not only compile your program with these flags,
# but also link it with them as well.
#
# If you want to compile everything with OpenMP, you should set:
#
# CFLAGS="$CFLAGS $OPENMP_CFLAGS"
# #OR# CXXFLAGS="$CXXFLAGS $OPENMP_CXXFLAGS"
# #OR# FFLAGS="$FFLAGS $OPENMP_FFLAGS"
#
# (depending on the selected language).
#
# The user can override the default choice by setting the corresponding
# environment variable (e.g. OPENMP_CFLAGS).
#
# ACTION-IF-FOUND is a list of shell commands to run if an OpenMP flag is
# found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it is
# not found. If ACTION-IF-FOUND is not specified, the default action will
# define HAVE_OPENMP.
#
# LICENSE
#
# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
#
# 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 <http://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 9
AC_DEFUN([AX_OPENMP], [
AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
AC_CACHE_CHECK([for OpenMP flag of _AC_LANG compiler], ax_cv_[]_AC_LANG_ABBREV[]_openmp, [save[]_AC_LANG_PREFIX[]FLAGS=$[]_AC_LANG_PREFIX[]FLAGS
ax_cv_[]_AC_LANG_ABBREV[]_openmp=unknown
# Flags to try: -fopenmp (gcc), -openmp (icc), -mp (SGI & PGI),
# -xopenmp (Sun), -omp (Tru64), -qsmp=omp (AIX), none
ax_openmp_flags="-fopenmp -openmp -mp -xopenmp -omp -qsmp=omp none"
if test "x$OPENMP_[]_AC_LANG_PREFIX[]FLAGS" != x; then
ax_openmp_flags="$OPENMP_[]_AC_LANG_PREFIX[]FLAGS $ax_openmp_flags"
fi
for ax_openmp_flag in $ax_openmp_flags; do
case $ax_openmp_flag in
none) []_AC_LANG_PREFIX[]FLAGS=$save[]_AC_LANG_PREFIX[] ;;
*) []_AC_LANG_PREFIX[]FLAGS="$save[]_AC_LANG_PREFIX[]FLAGS $ax_openmp_flag" ;;
esac
AC_TRY_LINK([#ifdef __cplusplus
extern "C"
#endif
void omp_set_num_threads(int);], [const int N = 100000;
int i, arr[N];
omp_set_num_threads(2);
#pragma omp parallel for
for (i = 0; i < N; i++) {
arr[i] = i;
}], [ax_cv_[]_AC_LANG_ABBREV[]_openmp=$ax_openmp_flag; break])
done
[]_AC_LANG_PREFIX[]FLAGS=$save[]_AC_LANG_PREFIX[]FLAGS
])
if test "x$ax_cv_[]_AC_LANG_ABBREV[]_openmp" = "xunknown"; then
m4_default([$2],:)
else
if test "x$ax_cv_[]_AC_LANG_ABBREV[]_openmp" != "xnone"; then
OPENMP_[]_AC_LANG_PREFIX[]FLAGS=$ax_cv_[]_AC_LANG_ABBREV[]_openmp
fi
m4_default([$1], [AC_DEFINE(HAVE_OPENMP,1,[Define if OpenMP is enabled])])
fi
])dnl AX_OPENMP
|