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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/109991] stack-use-after-scope
Date: Fri, 26 May 2023 19:59:32 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109991

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to igk from comment #3)
> (In reply to Andrew Pinski from comment #2)
> > Dup of bug 98675.
> >=20
> > *** This bug has been marked as a duplicate of bug 98675 ***
>=20
> Thanks for looking into this. I haven't quite understood though.=20

Let me reword of what is going on and why it is still is a dup. So the
constexpr should be ignored because it is undefined code. But since GCC does
not detect the undefineness yet (this is what PR 98675 is about), GCC decid=
es
that it is still a constexpr and evaluates it at compile time and removes t=
he
ability for the sanitizer to detect the undefinedness at runtime.=