Index: tool/lempar.c
==================================================================
--- tool/lempar.c
+++ tool/lempar.c
@@ -548,10 +548,11 @@
           j>=0 &&
 #endif
 #if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
           j<YY_ACTTAB_COUNT &&
 #endif
+          j<sizeof(yy_lookahead)/sizeof(yy_lookahead[0]) &&
           yy_lookahead[j]==YYWILDCARD && iLookAhead>0
         ){
 #ifndef NDEBUG
           if( yyTraceFILE ){
             fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",