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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/71699] bogus -Wmaybe-uninitialized warning: gcc
 misses that non-NULL pointer + offset can never be NULL
Date: Wed, 31 Mar 2021 21:11:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D71699

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |9.0
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED
                 CC|                            |msebor at gcc dot gnu.org
      Known to work|                            |9.3.0
      Known to fail|                            |7.3.0, 8.3.0

--- Comment #13 from Martin Sebor <msebor at gcc dot gnu.org> ---
At -O1 and above the warning has disappeared with r263662 (GCC 9.0.0 201808=
20).

It's still on trunk with -O0 (and with -Og) not with higher optimization
levels.  But I'm not sure I see this as a problem.  The test case assigns an
uninitialized variable for no apparent reason and expects the assignment to=
 be
eliminated.  That does happen but only with optimization.  The warning could
probably be enhanced to figure this out by essentially implementing the same
logic as the optimization does but that seems like going too far.  With so =
many
open bugs against -Wuninitialized of higher priority with no progress for a
decade or more I'm going to resolve this one as fixed.=