[Bug tree-optimization/56448] [4.8 Regression] cc1 hangs on volatile array with -O or above

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56448



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



           What    |Removed                     |Added

----------------------------------------------------------------------------

             Status|UNCONFIRMED                 |NEW

   Last reconfirmed|                            |2013-02-25

                 CC|                            |jakub at gcc dot gnu.org

   Target Milestone|---                         |4.8.0

            Summary|cc1 hangs on volatile array |[4.8 Regression] cc1 hangs

                   |with -O or above            |on volatile array with -O

                   |                            |or above

     Ever Confirmed|0                           |1



--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-25 
22:17:01 UTC ---

Started with my http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=195136 fix.

I think the problem is that for:

tree val; // which is &a[0] where a is volatile array

operand_equal_p (val, unshare_expr (val), OEP_PURE_SAME)

is false.