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Subject: [Bug lto/47936] [4.6 Regression] Missed optimization with LTO due to strict aliasing issues
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47936

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.03.01 10:28:51
   Target Milestone|---                         |4.6.0
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-01 10:28:51 UTC ---
Confirmed.  This one happens because we merge struct S and struct T for
TBAA purposes (they get the same TYPE_CANONICAL).

This is by design to allow cross-language (and slightly invalid) code to
not fall over TBAA issues too easily.