[Bug tree-optimization/49115] [4.5/4.6 Regression] invalid return value optimization (?) when exception is thrown and caught

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49115

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-06-17 
11:27:41 UTC ---
Author: rguenth
Date: Fri Jun 17 11:27:37 2011
New Revision: 175148

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=175148
Log:
2011-06-17  Richard Guenther  <rguent...@suse.de>

        Backport from mainline
        2011-05-23  Richard Guenther  <rguent...@suse.de>

    PR tree-optimization/49115
    * tree-ssa-alias.c (stmt_kills_ref_p_1): If the assignment
    is not necessarily carried out, do not claim it kills the ref.
    * tree-ssa-dce.c (mark_aliased_reaching_defs_necessary_1): Likewise.

    * g++.dg/torture/pr49115.C: New testcase.

Added:
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/torture/pr49115.C
Modified:
    branches/gcc-4_6-branch/gcc/ChangeLog
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_6-branch/gcc/tree-ssa-alias.c
    branches/gcc-4_6-branch/gcc/tree-ssa-dce.c