diff --git a/tools/lemon/lempar.c b/tools/lemon/lempar.c
index dbdccc0e7c..799eb24b12 100644
--- a/tools/lemon/lempar.c
+++ b/tools/lemon/lempar.c
@@ -398,55 +398,60 @@ static int yy_find_shift_action(
 ){
   int i;
   int stateno = pParser->yystack[pParser->yyidx].stateno;
-
-  if( stateno>=YY_MIN_REDUCE ) return stateno; 
+ 
+  if( stateno>=YY_MIN_REDUCE ) return stateno;
   assert( stateno <= YY_SHIFT_COUNT );
-  i = yy_shift_ofst[stateno];
-  if( i==YY_SHIFT_USE_DFLT ) return yy_default[stateno];
-  assert( iLookAhead!=YYNOCODE );
-  i += iLookAhead;
-  if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
-    if( iLookAhead>0 ){
+  do{
+    i = yy_shift_ofst[stateno];
+    if( i==YY_SHIFT_USE_DFLT ) return yy_default[stateno];
+    assert( iLookAhead!=YYNOCODE );
+    i += iLookAhead;
+    if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
+      if( iLookAhead>0 ){
 #ifdef YYFALLBACK
-      YYCODETYPE iFallback;            /* Fallback token */
-      if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
-             && (iFallback = yyFallback[iLookAhead])!=0 ){
-#ifndef NDEBUG
-        if( yyTraceFILE ){
-          fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
-             yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
-        }
-#endif
-        return yy_find_shift_action(pParser, iFallback);
-      }
-#endif
-#ifdef YYWILDCARD
-      {
-        int j = i - iLookAhead + YYWILDCARD;
-        if( 
-#if YY_SHIFT_MIN+YYWILDCARD<0
-          j>=0 &&
-#endif
-#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
-          j<YY_ACTTAB_COUNT &&
-#endif
-          yy_lookahead[j]==YYWILDCARD
-        ){
+        YYCODETYPE iFallback;            /* Fallback token */
+        if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
+               && (iFallback = yyFallback[iLookAhead])!=0 ){
 #ifndef NDEBUG
           if( yyTraceFILE ){
-            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
-               yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]);
+            fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
+               yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
+          }
+#endif
+          assert( yyFallback[iFallback]==0 ); /* Fallback loop must terminate */
+          iLookAhead = iFallback;
+          continue;
+        }
+#endif
+#ifdef YYWILDCARD
+        {
+          int j = i - iLookAhead + YYWILDCARD;
+          if( 
+#if YY_SHIFT_MIN+YYWILDCARD<0
+            j>=0 &&
+#endif
+#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
+            j<YY_ACTTAB_COUNT &&
+#endif
+            yy_lookahead[j]==YYWILDCARD
+          ){
+#ifndef NDEBUG
+            if( yyTraceFILE ){
+              fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
+                 yyTracePrompt, yyTokenName[iLookAhead],
+                 yyTokenName[YYWILDCARD]);
+            }
+#endif /* NDEBUG */
+            return yy_action[j];
           }
-#endif /* NDEBUG */
-          return yy_action[j];
         }
-      }
 #endif /* YYWILDCARD */
+      }
+      return yy_default[stateno];
+    }else{
+      return yy_action[i];
     }
-    return yy_default[stateno];
-  }else{
-    return yy_action[i];
-  }
+  }while(1);
 }
 
 /*
@@ -625,6 +630,7 @@ static void yy_reduce(
   */
 %%
   };
+  assert( yyruleno>=0 && yyruleno<sizeof(yyRuleInfo)/sizeof(yyRuleInfo[0]) );
   yygoto = yyRuleInfo[yyruleno].lhs;
   yysize = yyRuleInfo[yyruleno].nrhs;
   yypParser->yyidx -= yysize;
@@ -732,7 +738,9 @@ void Parse(
 ){
   YYMINORTYPE yyminorunion;
   int yyact;            /* The parser action. */
+#if !defined(YYERRORSYMBOL) && !defined(YYNOERRORRECOVERY)
   int yyendofinput;     /* True if we are at the end of input */
+#endif
 #ifdef YYERRORSYMBOL
   int yyerrorhit = 0;   /* True if yymajor has invoked an error */
 #endif
@@ -755,7 +763,9 @@ void Parse(
     yypParser->yystack[0].major = 0;
   }
   yyminorunion.yy0 = yyminor;
+#if !defined(YYERRORSYMBOL) && !defined(YYNOERRORRECOVERY)
   yyendofinput = (yymajor==0);
+#endif
   ParseARG_STORE;
 
 #ifndef NDEBUG