help required on bison.simple

[psadhukhan]

Hi All,

I am using GNU bison version 1.28 to parse SIP protocol messages.  My code
was being tested with
Purify memory debugger. I face the following problem :

For some messages I find that the following piece of code in the file
"bison.simple" is getting executed and
throwing up a Array Bounds Read error at the location specified below with
==>


<snip>
/* PATCH1: typecast sizeof to return int */
          for (x = (yyn < 0 ? -yyn : 0);
               x < (int)(sizeof(yytname) / sizeof(char *)); x++)
==>   if (yycheck[x + yyn] == x)
              size += strlen(yytname[x]) + 15, count++;
          msg = (char *) malloc(size + 15);
          if (msg != 0)
          {
              strcpy(msg, "parse error");

              if (count < 5)
                {
                  count = 0;
                  for (x = (yyn < 0 ? -yyn : 0);
<snip>

The question is when can this error occur ? Has anybody else faced the same
 problem?
Any pointers towards the solution would be very helpful.

Regards
Prateek







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