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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/98130] [11 regression] placement new fails on
 webkit-gtk-2.28.4 since r11-4745-g58c9de46541ade79
Date: Fri, 04 Dec 2020 13:33:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98130

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #8)
> Oops, yes, dunno why it didn't work for me before, confirmed now that it
> works with the patch and fails without.
>=20
> I think we want it even for the operator delete case, I believe the C++
> standard only constraints how the replaceable operators work, not arbitra=
ry
> user operator new/delete/new[]/delete[] operators.

Note we already require to see a new/delete _expression_ and IIRC any delete
expression will make the contents undefined (see my discussion with Jason on
this topic).  But yes, we have to preserve other side-effects so the ".c"
part is probably bogus, the PTA code treats it as "..X ", "..o " would
still make 'this' receive pointers.  So we probably cannot model 'delete'
beavior exactly but "..o " is probably good enough.  Attempts to break it
welcome, of course.=