[GRASSLIST:5299] r.los failure

[Ron Yorston]

I recently built GRASS 5.4 on Fedora Core 3.  r.los was failing with:

   *** glibc detected *** double free or corruption (out): 0xbfe86400 ***
   Aborted (core dumped)

This turned out to be due to the call to segment_release(&seg_patt) on
line 383 of main.c.  Since I wasn't using a patt_map argument seg_patt had
never been initialised.  A possible fix is:

   if(patt_flag == 1)
   {
      segment_release(&seg_patt);
   }

Ron