1 # =========================================================================== 2 # http://www.gnu.org/software/autoconf-archive/ax_prog_bison.html 3 # =========================================================================== 4 # 5 # SYNOPSIS 6 # 7 # AX_PROG_BISON(ACTION-IF-TRUE,ACTION-IF-FALSE) 8 # 9 # DESCRIPTION 10 # 11 # Check whether bison is the parser generator. Run ACTION-IF-TRUE if 12 # successful, ACTION-IF-FALSE otherwise 13 # 14 # LICENSE 15 # 16 # Copyright (c) 2009 Francesco Salvestrini <salvestrini (a] users.sourceforge.net> 17 # Copyright (c) 2010 Diego Elio Petteno` <flameeyes (a] gmail.com> 18 # 19 # This program is free software; you can redistribute it and/or modify it 20 # under the terms of the GNU General Public License as published by the 21 # Free Software Foundation; either version 2 of the License, or (at your 22 # option) any later version. 23 # 24 # This program is distributed in the hope that it will be useful, but 25 # WITHOUT ANY WARRANTY; without even the implied warranty of 26 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 27 # Public License for more details. 28 # 29 # You should have received a copy of the GNU General Public License along 30 # with this program. If not, see <http://www.gnu.org/licenses/>. 31 # 32 # As a special exception, the respective Autoconf Macro's copyright owner 33 # gives unlimited permission to copy, distribute and modify the configure 34 # scripts that are the output of Autoconf when processing the Macro. You 35 # need not follow the terms of the GNU General Public License when using 36 # or distributing such scripts, even though portions of the text of the 37 # Macro appear in them. The GNU General Public License (GPL) does govern 38 # all other use of the material that constitutes the Autoconf Macro. 39 # 40 # This special exception to the GPL applies to versions of the Autoconf 41 # Macro released by the Autoconf Archive. When you make and distribute a 42 # modified version of the Autoconf Macro, you may extend this special 43 # exception to the GPL to apply to your modified version as well. 44 45 #serial 9 46 47 # mattst88: 48 # Modified YACC assignment to remove -o y.tab.c since we're writing 49 # our own .y/.yy rules. 50 # 51 # Replaced m4_ifnblank(...) with m4_ifval(m4_normalize(...), ...) 52 # since m4_ifnblank requires autoconf-2.64. 53 54 AC_DEFUN([AX_PROG_BISON], [ 55 AC_REQUIRE([AC_PROG_YACC]) 56 AC_REQUIRE([AC_PROG_EGREP]) 57 58 AC_CACHE_CHECK([if bison is the parser generator],[ax_cv_prog_bison],[ 59 AS_IF([$YACC --version 2>/dev/null | $EGREP -q '^bison '], 60 [ax_cv_prog_bison=yes], [ax_cv_prog_bison=no]) 61 ]) 62 AS_IF([test "$ax_cv_prog_bison" = "yes"], [ 63 dnl replace the yacc-compatible compiler with the real bison, as 64 dnl otherwise autoconf limits us to the POSIX yacc. 65 dnl We also change the generated filename to the old one, so that 66 dnl automake's ylwrap can deal with it. 67 YACC="${YACC% -y}" 68 ] m4_ifval(m4_normalize([$1]), [[$1]]), 69 m4_ifval(m4_normalize([$2]), [[$2]]) 70 ) 71 ]) 72
