X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fbison.m4;h=eb05c36eac6d7dfc0e231a97c1ab03f1216b18b9;hb=cbe36a5b0bb5fed005e9e3d24c06ef07b69620c6;hp=c4854b273ace9a0bf7d89893a921d24fa5ccd6f6;hpb=23fe10e274cf20fb2cb75ea1da9556a733106657;p=gnulib.git

diff --git a/m4/bison.m4 b/m4/bison.m4
index c4854b273..eb05c36ea 100644
--- a/m4/bison.m4
+++ b/m4/bison.m4
@@ -1,8 +1,24 @@
-#serial 3
+# serial 5
+
+# Copyright (C) 2002, 2005, 2009 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_BISON],
 [
   # getdate.y works with bison only.
   : ${YACC='bison -y'}
-  AC_SUBST(YACC)
+dnl
+dnl Declaring YACC & YFLAGS precious will not be necessary after GNULIB
+dnl requires an Autoconf greater than 2.59c, but it will probably still be
+dnl useful to override the description of YACC in the --help output, re
+dnl getdate.y assuming `bison -y'.
+  AC_ARG_VAR([YACC],
+[The `Yet Another C Compiler' implementation to use.  Defaults to `bison -y'.
+Values other than `bison -y' will most likely break on most systems.])dnl
+  AC_ARG_VAR([YFLAGS],
+[YFLAGS contains the list arguments that will be passed by default to Bison.
+This script will default YFLAGS to the empty string to avoid a default value of
+`-d' given by some make applications.])dnl
 ])