[Bug tree-optimization/68021] [6 Regression] ice in rewrite_use_nonlinear_expr with -O3

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68021

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
      Known to work|                            |4.9.3, 5.2.0
   Last reconfirmed|                            |2015-10-19
          Component|c++                         |tree-optimization
                 CC|                            |trippels at gcc dot gnu.org
     Ever confirmed|0                           |1
            Summary|ice in                      |[6 Regression] ice in
                   |rewrite_use_nonlinear_expr  |rewrite_use_nonlinear_expr
                   |with -O3                    |with -O3
      Known to fail|                            |6.0

--- Comment #1 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Needs -O3:

char a;
int b;
void fn1(char *p1, int p2, int p3) {
  int x;
  for (; b;) {
    for (x = 0; x < p3; x++) {
      *p1 = a;
      p1--;
    }
    p1 += p2;
  }
}