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Subject: [Bug tree-optimization/49234] [4.6/4.7/4.8 Regression] -Wstrict-overflow gives obviously unwarranted warning
Date: Wed, 06 Mar 2013 08:56:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49234

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.5/4.6/4.7/4.8            |[4.6/4.7/4.8 Regression]
                   |Regression]                 |-Wstrict-overflow gives
                   |-Wstrict-overflow gives     |obviously unwarranted
                   |obviously unwarranted       |warning
                   |warning                     |

--- Comment #17 from Richard Biener <rguenth at gcc dot gnu.org> 2013-03-06 08:55:46 UTC ---
The patch is a hack.  Comparing SSA_NAME_VAR is very fragile, nothing but
debug info cares about SSA_NAME_VAR.

I can't see why constant PHI arguments should be in any way special - in
fact this is just the very usual induction variable PHI with a constant
initial value ...