[Bug tree-optimization/54498] [4.7/4.8 Regression] incorrect code generation from g++ -O

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54498

--- Comment #3 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-06 10:21:36 UTC ---
Testing

Index: gcc/tree-ssa-alias.c
===================================================================
--- gcc/tree-ssa-alias.c        (revision 191016)
+++ gcc/tree-ssa-alias.c        (working copy)
@@ -2094,7 +2094,10 @@ walk_non_aliased_vuses (ao_ref *ref, tre
              /* Lookup succeeded.  */
              else if (res != NULL)
                break;
-             /* Translation succeeded, continue walking.  */
+             /* Translation succeeded, continue walking.  We have to
+                again visit cycles though.  */
+             if (visited)
+               bitmap_clear (visited);
            }
          vuse = gimple_vuse (def_stmt);
        }