--- bison.simple.cvs	Tue Jun 11 18:25:32 2002
+++ bison.simple	Tue Jun 11 18:29:24 2002
@@ -1118,9 +1118,40 @@
 
       /* Return failure if at end of input.  */
       if (yychar == YYEOF)
-	YYABORT;
+      {
+
+#ifdef YYERROR_POP
+
+/* YYERROR_POP can be defined as an operation to be called in the event
+   that the parser needs to pop state from the top of the stack, during
+   error recovery or at YYEOF. The argument has type YYSTYPE *  It will
+   actually point to an object. The operation can access the variable by
+   casting it to the proper pointer type. 
+
+   YYERROR_POP and YYERROR_DISCARD can be used (for example) to free
+   storage allocated for semantic tokens by grammar rules or the lexer.  */
+   
+         YYPOPSTACK;
+         while (yyssp > yyss) {
+	    YYERROR_POP(yyvsp);
+	    YYPOPSTACK;
+	 }
+
+#endif
+         YYABORT;
+      }
+
       YYDPRINTF ((stderr, "Discarding token %d (%s).\n",
 		  yychar, yytname[yychar1]));
+
+#ifdef YYERROR_DISCARD
+/* YYERROR_DISCARD can be defined as an operation to be called in the event
+   that error recovery needs to discard a lookahead token.  The argument should
+   have type YYSTYPE.  */
+
+      YYERROR_DISCARD(yylval);
+#endif
+
       yychar = YYEMPTY;
     }
 
@@ -1145,6 +1176,11 @@
 
       /* Pop the current state because it cannot handle the error token.  */
       if (yyssp == yyss)
+#ifdef YYERROR_POP
+        if (yystate>1) { /* don't call for the error token, or YYEOF */
+          YYERROR_POP(yyvsp);
+        }
+#endif
 	YYABORT;
 
 #if YYDEBUG