1 # Copyright 2000 Free Software Foundation, Inc.
3 # This program is free software: you can redistribute it and/or modify
4 # it under the terms of the GNU General Public License as published by
5 # the Free Software Foundation, either version 3 of the License, or
6 # (at your option) any later version.
8 # This program is distributed in the hope that it will be useful,
9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 # GNU General Public License for more details.
13 # You should have received a copy of the GNU General Public License
14 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18 # Check for GNU m4, at least 1.3 (supports frozen files).
19 AC_DEFUN([BISON_PROG_GNU_M4],
20 [AC_PATH_PROGS(M4, gm4 gnum4 m4, m4)
21 AC_CACHE_CHECK(whether m4 supports frozen files, ac_cv_prog_gnu_m4,
23 if test x"$M4" != x; then
24 case `$M4 --help < /dev/null 2>&1` in
25 *reload-state*) ac_cv_prog_gnu_m4=yes ;;