[Bug tree-optimization/79671] [7 Regression] mapnik miscompilation on armv7hl since r235622

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79671

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Repeated on current trunk r245696, this time with:
--- gcc/tree-ssa-alias.c.jj     2017-01-10 08:12:48.000000000 +0100
+++ gcc/tree-ssa-alias.c        2017-02-24 12:15:17.869368974 +0100
@@ -387,7 +387,13 @@ ptrs_compare_unequal (tree ptr1, tree pt
              || ! decl_binds_to_current_def_p (obj1))
            return false;
        }
-      return !pt_solution_includes (&pi->pt, obj1);
+      if (!pt_solution_includes (&pi->pt, obj1))
+{
+gcc_assert (TREE_CODE (ptr2) == SSA_NAME);
+int x = atoi (getenv ("PTRS_COMPARE_UNEQUAL"));
+debug_generic_stmt (ptr2);
+return SSA_NAME_VERSION (ptr2) == x;
+}
     }

   /* ???  We'd like to handle ptr1 != NULL and ptr1 != ptr2
hack.  Unpatched trunk fails, with -fno-tree-pre succeeds and with this hack
and PTRS_COMPARE_UNEQUAL=111111 succeeds as well.  Let me try the various ssa
name versions next.