--- /usr/share/bison/glr.c	2008-12-12 09:29:32.000000000 +0000
+++ glr.c	2009-04-04 01:07:36.000000000 +0100
@@ -2631,6 +2631,7 @@
 #endif
 ]
 
+m4_define(b4_header_prefix,m4_translit(b4_prefix, `[a-z:]', `[A-Z_]'))
 b4_epilogue
 dnl
 dnl glr.cc produces its own header.
@@ -2641,6 +2642,8 @@
 b4_copyright([Skeleton interface for Bison GLR parsers in C],
   [2002, 2003, 2004, 2005, 2006])
 
+#ifndef b4_header_prefix[]_PARSER_HEADER_H
+# define b4_header_prefix[]_PARSER_HEADER_H
 b4_shared_declarations
 
 b4_pure_if([],
@@ -2650,4 +2653,5 @@
 [extern YYLTYPE ]b4_prefix[lloc;])
 ])
 ])])
+#endif /* !b4_header_prefix[]_PARSER_HEADER_H */
 m4_divert_pop(0)