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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/109770] [10/11/12/13/14 Regression] wrong(?)
 devirtualization
Date: Mon, 08 May 2023 17:21:11 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109770

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

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

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
So we devirtualize during FRE1:

Determining dynamic type for call: OBJ_TYPE_REF(_3;(struct Base)_7->1B) (_7=
);
  Starting walk at: _1 =3D MEM[(struct Base *)_7]._vptr.Base;
  instance pointer: _7  Outer instance pointer: _7 offset: 0 (bits) vtbl
reference: MEM[(struct Base *)_7]._vptr.Base
  Checking constructor call: B::B (_7);
  Recording type: struct B at offset 0
  Determined dynamic type.

so eventually the CTOR call handling needs to be removed if we cannot
rely on that producing a specific dynamically typed object.

Any C++ experts?=