[Bug middle-end/35534] Problem compiling gdb/symtab.c in GDB 6.7.1 using GCC 4.3.0 on Solaris 10

[jonathan dot leffler at gmail dot com]

------- Comment #5 from jonathan dot leffler at gmail dot com  2008-03-11 04:04 -------
After a 'mid-air collision':

    The code for find_line_common() is in the same file, later on, but declared
static, so GCC can analyze it -- and then it is correct to complain:


    static int
    find_line_common (struct linetable *l, int lineno,
              int *exact_match)
    {
      int i;
      int len;

      /* BEST is the smallest linenumber > LINENO so far seen,
         or 0 if none has been seen so far.
         BEST_INDEX identifies the item for it.  */

      int best_index = -1;
      int best = 0;

      if (lineno <= 0)
        return -1;
      if (l == 0)
        return -1;

      len = l->nitems;
      for (i = 0; i < len; i++)
        {
          struct linetable_entry *item = &(l->item[i]);

          if (item->line == lineno)
        {
          /* Return the first (lowest address) entry which matches.  */
          *exact_match = 1;
          return i;
        }

          if (item->line > lineno && (best == 0 || item->line < best))
        {
          best = item->line;
          best_index = i;
        }
        }

      /* If we got here, we didn't get an exact match.  */

      *exact_match = 0;
      return best_index;
    }

    The two early exits do leave exact unset.  However, those cases leave
best_index in find_line_symtab less than zero, so the test would not access
exact in those cases.  It is a bit hard for GCC to note that for all other
return cases, the returned value assigned to best_index is non-negative and
that exact is then set.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35534