[Bug middle-end/40135] using alias-set zero for union accesses necessary because of RTL alias oracle

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=40135

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
             Blocks|                            |71002
         Resolution|---                         |FIXED

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed by

2016-06-29  Richard Biener  <rguenther@suse.de>

        PR middle-end/71002
        * c-common.c (c_common_get_alias_set): Remove union type punning case.

        * alias.c (component_uses_parent_alias_set_from): Handle
        type punning through union accesses by using the union alias set.
        * gimple.c (gimple_get_alias_set): Remove union type punning case.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71002
[Bug 71002] [6 Regression] -fstrict-aliasing breaks Boost's short string
optimization implementation