(yyparse): Correct error handling to conform to

POSIX and yacc.  Specifically, after syntax error is discovered,
do not reduce further before shifting the error token.
Clean up the code a bit by removing the labels yyerrdefault,
yyerrhandle, yyerrpop.

diff --git a/data/bison.simple b/data/bison.simple
index ad42a9193cdab22b08d471f308567515d5307d24..7a491feb8d9ae9b93b4fddd5163492cbea2abf43 100644 (file)
--- a/data/bison.simple
+++ b/data/bison.simple
@@ -1120,71 +1120,40 @@ yyerrlab1:
 
   yyerrstatus = 3;     /* Each real token shifted decrements this.  */
 
 
   yyerrstatus = 3;     /* Each real token shifted decrements this.  */
 

-  goto yyerrhandle;
-
-
-/*-------------------------------------------------------------------.
-| yyerrdefault -- current state does not do anything special for the |
-| error token.                                                       |
-`-------------------------------------------------------------------*/
-yyerrdefault:
-#if 0
-  /* This is wrong; only states that explicitly want error tokens
-     should shift them.  */
-
-  /* If its default is to accept any token, ok.  Otherwise pop it.  */
-  yyn = yydefact[yystate];
-  if (yyn)
-    goto yydefault;
-#endif
-
+  for (;;)
+    {
+      yyn = yypact[yystate];
+      if (yyn != YYFLAG)
+       {
+         yyn += YYTERROR;
+         if (0 <= yyn && yyn <= YYLAST && yycheck[yyn] == YYTERROR)
+           {
+             yyn = yytable[yyn];
+             if (0 < yyn)
+               break;
+           }
+       }

 
 

-/*---------------------------------------------------------------.
-| yyerrpop -- pop the current state because it cannot handle the |
-| error token.                                                   |
-`---------------------------------------------------------------*/
-yyerrpop:
-  if (yyssp == yyss)
-    YYABORT;
-  yyvsp--;
-  yystate = *--yyssp;
+      /* Pop the current state because it cannot handle the error token.  */
+      if (yyssp == yyss)
+       YYABORT;
+      yyvsp--;
+      yystate = *--yyssp;

 #if YYLSP_NEEDED
 #if YYLSP_NEEDED

-  yylsp--;
+      yylsp--;

 #endif
 
 #if YYDEBUG
 #endif
 
 #if YYDEBUG

-  if (yydebug)
-    {
-      short *yyssp1 = yyss - 1;
-      YYFPRINTF (stderr, "Error: state stack now");
-      while (yyssp1 != yyssp)
-       YYFPRINTF (stderr, " %d", *++yyssp1);
-      YYFPRINTF (stderr, "\n");
-    }
+      if (yydebug)
+       {
+         short *yyssp1 = yyss - 1;
+         YYFPRINTF (stderr, "Error: state stack now");
+         while (yyssp1 != yyssp)
+           YYFPRINTF (stderr, " %d", *++yyssp1);
+         YYFPRINTF (stderr, "\n");
+       }

 #endif
 #endif

-
-/*--------------.
-| yyerrhandle.  |
-`--------------*/
-yyerrhandle:
-  yyn = yypact[yystate];
-  if (yyn == YYFLAG)
-    goto yyerrdefault;
-
-  yyn += YYTERROR;
-  if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != YYTERROR)
-    goto yyerrdefault;
-
-  yyn = yytable[yyn];
-  if (yyn < 0)
-    {
-      if (yyn == YYFLAG)
-       goto yyerrpop;
-      yyn = -yyn;
-      goto yyreduce;

     }
     }

-  else if (yyn == 0)
-    goto yyerrpop;

 
   if (yyn == YYFINAL)
     YYACCEPT;
 
   if (yyn == YYFINAL)
     YYACCEPT;