[Bug tree-optimization/16306] New: restrict and copying pointers problem

["dann at godzilla dot ics dot uci dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

The current mainline does not optimize away the "link_error" call for this function:

void bar00 (int *a1, int *a2)
{
  int * __restrict__ cpy_res1 = a1;
  int * __restrict__ cpy_res2 = a2;
  cpy_res1[0] = 1;
  cpy_res2[0] = 1;
  if (cpy_res1[0] != 1)
    link_error ();
}

gcc-3.0 optimizes it. 

What happens is that the dom1 pass replaces the uses of cpy_res[12] (which are
restricted pointers)  with a[12] (which are not), so the RTL optimizers cannot
know that the "if" can be optimized away. 

This issue might be sort of related to PR14187. 


PR 14187

-- 
           Summary: restrict and copying pointers problem
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dann at godzilla dot ics dot uci dot edu
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16306