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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/114245] Defaulted virtual destructors that do no work
 overwrite the vtable with `-O0`
Date: Wed, 06 Mar 2024 16:38:42 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114245

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

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

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #4)
> Updating the vtable is necessary during destruction if a later (i.e. less
> derived) destructor calls a virtual function. But if we can tell that the
> current dtor and all later base dtors are trivial, then we know that can't
> happen.
>=20
> If the front end detected that case, we wouldn't need to rely on dead sto=
re
> elimination.

But isn't that just an optimization the user asked not to perform (with usi=
ng
-O0)?
I mean, e.g. the user could care about the vtable updates for e.g. calling
methods
from the debugger as the destruction of the object progresses.=