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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/104492] [12 Regression] Bogus dangling pointer
 warning at -O3
Date: Wed, 20 Apr 2022 08:52:57 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104492

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Any progress on this?  It is a P1...
As Richi said, CLOBBERs have vops and prevent moving of memory reads/writes
across them, but can't prevent moving of just addresses of those vars across
them, such a dependence isn't present in the IL.
So, can CLOBBERs be used for warning diagnosing out of scope accesses to
variables?  Sure.  Can CLOBBERs be used for warning diagnosing references to
address of out of scope variables?  No (perhaps with the exception of
GIMPLE_RETURN of such addresses, returning that to a caller is certainly
suspicious).=