diff -Naur cproto-4.6-old/cproto.h cproto-4.6/cproto.h
--- cproto-4.6-old/cproto.h	1998-01-18 19:49:16.000000000 -0500
+++ cproto-4.6/cproto.h	2004-03-14 00:02:32.148070032 -0500
@@ -117,6 +117,7 @@
     Declarator *declarator;
     DeclaratorList decl_list;
 } YYSTYPE;
+#define YYSTYPE_IS_DECLARED 1
 
 /* Prototype styles */
 #if OPT_LINTLIBRARY