[Bug tree-optimization/49079] [4.6/4.7 Regression] Bogus constant folding

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49079

--- Comment #9 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-05-20 15:08:59 UTC ---
Author: rguenth
Date: Fri May 20 15:08:56 2011
New Revision: 173955

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=173955
Log:
2011-05-20  Richard Guenther  <rguenther@suse.de>

    PR tree-optimization/49079
    * tree-dfa.c (get_ref_base_and_extent): Handle view-converting
    MEM_REFs correctly for the trailing array access detection.
    Special case constants the same way as decls for overall size
    constraining.

    * gcc.dg/torture/pr49079.c: New testcase.

Added:
    branches/gcc-4_6-branch/gcc/testsuite/gcc.dg/torture/pr49079.c
Modified:
    branches/gcc-4_6-branch/gcc/ChangeLog
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_6-branch/gcc/tree-dfa.c