[Bug tree-optimization/49926] [4.7 Regression] ice in process_use, at tree-vect-stmts.c:405

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49926

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
           Keywords|                            |ice-on-valid-code
   Last reconfirmed|                            |2011.07.31 22:33:53
          Component|c                           |tree-optimization
                 CC|                            |jakub at gcc dot gnu.org
     Ever Confirmed|0                           |1
            Summary|ice in process_use, at      |[4.7 Regression] ice in
                   |tree-vect-stmts.c:405       |process_use, at
                   |                            |tree-vect-stmts.c:405
   Target Milestone|---                         |4.7.0

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-07-31 
22:33:53 UTC ---
Confirmed, started at http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=173856
Reduced testcase at -O3 on x86_64-linux:
int b, c[10];

void
foo (unsigned int x, int y, int z, int *w)
{
  do
    {
      *w = z;
      y = x;
      if (y)
        for (b = -4; b; b++)
          {
            z = y &= 1;
            y &= c[b + 4];
          }
    }
  while (1);
}