1 # Copyright 2000 Free Software Foundation, Inc. 2 # 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 2, or (at your option) 6 # any later version. 7 # 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. 12 # 13 # You should have received a copy of the GNU General Public License 14 # along with this program; if not, write to the Free Software 15 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 # 02110-1301, USA. 17 18 # BISON_PROG_GNU_M4 19 # ----------------- 20 # Check for GNU m4, at least 1.3 (supports frozen files). 21 AC_DEFUN([BISON_PROG_GNU_M4], 22 [AC_PATH_PROGS(M4, gm4 gnum4 m4, m4) 23 AC_CACHE_CHECK(whether m4 supports frozen files, ac_cv_prog_gnu_m4, 24 [ac_cv_prog_gnu_m4=no 25 if test x"$M4" != x; then 26 case `$M4 --help < /dev/null 2>&1` in 27 *reload-state*) ac_cv_prog_gnu_m4=yes ;; 28 esac 29 fi])]) 30