1 # ===========================================================================
2 # http://www.nongnu.org/autoconf-archive/ax_openmp.html
3 # ===========================================================================
7 # AX_OPENMP([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
11 # This macro tries to find out how to compile programs that use OpenMP a
12 # standard API and set of compiler directives for parallel programming
13 # (see http://www-unix.mcs/)
15 # On success, it sets the OPENMP_CFLAGS/OPENMP_CXXFLAGS/OPENMP_F77FLAGS
16 # output variable to the flag (e.g. -omp) used both to compile *and* link
17 # OpenMP programs in the current language.
19 # NOTE: You are assumed to not only compile your program with these flags,
20 # but also link it with them as well.
22 # If you want to compile everything with OpenMP, you should set:
24 # CFLAGS="$CFLAGS $OPENMP_CFLAGS"
25 # #OR# CXXFLAGS="$CXXFLAGS $OPENMP_CXXFLAGS"
26 # #OR# FFLAGS="$FFLAGS $OPENMP_FFLAGS"
28 # (depending on the selected language).
30 # The user can override the default choice by setting the corresponding
31 # environment variable (e.g. OPENMP_CFLAGS).
33 # ACTION-IF-FOUND is a list of shell commands to run if an OpenMP flag is
34 # found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it is
35 # not found. If ACTION-IF-FOUND is not specified, the default action will
40 # Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
42 # This program is free software: you can redistribute it and/or modify it
43 # under the terms of the GNU General Public License as published by the
44 # Free Software Foundation, either version 3 of the License, or (at your
45 # option) any later version.
47 # This program is distributed in the hope that it will be useful, but
48 # WITHOUT ANY WARRANTY; without even the implied warranty of
49 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
50 # Public License for more details.
52 # You should have received a copy of the GNU General Public License along
53 # with this program. If not, see <http://www.gnu.org/licenses/>.
55 # As a special exception, the respective Autoconf Macro's copyright owner
56 # gives unlimited permission to copy, distribute and modify the configure
57 # scripts that are the output of Autoconf when processing the Macro. You
58 # need not follow the terms of the GNU General Public License when using
59 # or distributing such scripts, even though portions of the text of the
60 # Macro appear in them. The GNU General Public License (GPL) does govern
61 # all other use of the material that constitutes the Autoconf Macro.
63 # This special exception to the GPL applies to versions of the Autoconf
64 # Macro released by the Autoconf Archive. When you make and distribute a
65 # modified version of the Autoconf Macro, you may extend this special
66 # exception to the GPL to apply to your modified version as well.
68 AC_DEFUN([AX_OPENMP], [
69 AC_PREREQ(2.59) dnl for _AC_LANG_PREFIX
71 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
72 ax_cv_[]_AC_LANG_ABBREV[]_openmp=unknown
73 # Flags to try: -fopenmp (gcc), -openmp (icc), -mp (SGI & PGI),
74 # -xopenmp (Sun), -omp (Tru64), -qsmp=omp (AIX), none
75 ax_openmp_flags="-fopenmp -openmp -mp -xopenmp -omp -qsmp=omp none"
76 if test "x$OPENMP_[]_AC_LANG_PREFIX[]FLAGS" != x; then
77 ax_openmp_flags="$OPENMP_[]_AC_LANG_PREFIX[]FLAGS $ax_openmp_flags"
79 for ax_openmp_flag in $ax_openmp_flags; do
80 case $ax_openmp_flag in
81 none) []_AC_LANG_PREFIX[]FLAGS=$save[]_AC_LANG_PREFIX[] ;;
82 *) []_AC_LANG_PREFIX[]FLAGS="$save[]_AC_LANG_PREFIX[]FLAGS $ax_openmp_flag" ;;
84 AC_TRY_LINK_FUNC(omp_set_num_threads,
85 [ax_cv_[]_AC_LANG_ABBREV[]_openmp=$ax_openmp_flag; break])
87 []_AC_LANG_PREFIX[]FLAGS=$save[]_AC_LANG_PREFIX[]FLAGS
89 if test "x$ax_cv_[]_AC_LANG_ABBREV[]_openmp" = "xunknown"; then
92 if test "x$ax_cv_[]_AC_LANG_ABBREV[]_openmp" != "xnone"; then
93 OPENMP_[]_AC_LANG_PREFIX[]FLAGS=$ax_cv_[]_AC_LANG_ABBREV[]_openmp
95 m4_default([$1], [AC_DEFINE(HAVE_OPENMP,1,[Define if OpenMP is enabled])])