[Bug c++/80593] [7/8 Regression] GCC 7, aligned_storage and “dereferencing type-punned pointer will break strict-aliasing rules”

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80593

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Fri May 19 12:34:54 2017
New Revision: 248269

URL: https://gcc.gnu.org/viewcvs?rev=248269&root=gcc&view=rev
Log:
2017-05-19  Richard Biener  <rguent...@suse.de>

        PR c++/80593
        * c-warn.c (strict_aliasing_warning): Do not warn for accesses
        to alias-set zero memory.

        * g++.dg/warn/Wstrict-aliasing-bogus-char-2.C: New testcase.
        * g++.dg/warn/Wstrict-aliasing-6.C: Adjust expected outcome.

Added:
    trunk/gcc/testsuite/g++.dg/warn/Wstrict-aliasing-bogus-char-2.C
Modified:
    trunk/gcc/c-family/ChangeLog
    trunk/gcc/c-family/c-warn.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/warn/Wstrict-aliasing-6.C