[Bug rtl-optimization/77855] [7 Regression] wrong code at -O3 on x86_64-linux-gnu (in both 32-bit and 64-bit modes)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77855

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Oct  6 12:17:53 2016
New Revision: 240832

URL: https://gcc.gnu.org/viewcvs?rev=240832&root=gcc&view=rev
Log:
2016-10-06  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/77855
        * tree-ssa-pre.c (prune_clobbered_mems): Queue exprs to remove
        instead of removing the current item while iterating over the set
        which is not safe.

        * gcc.dg/torture/pr77855.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr77855.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-pre.c