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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/96416] to_address() is broken by static_assert in
 pointer_traits
Date: Tue, 20 Apr 2021 20:11:24 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96416

--- Comment #17 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Giuseppe D'Angelo from comment #14)
> To summarize:
>=20
> * should a wording defect be raised against std::to_address(Ptr), to state
> that pointer_traits<Ptr> being well-formed is actually a prerequisite?

I'd prefer if pointer_traits was just SFINAE friendly.

> * should LWG3446's resolution be amended?

See https://cplusplus.github.io/LWG/issue3541

> * if there's going to be a GCC 10.3, is the commit above solving LWG3446
> going to be cherry-picked into it? Otherwise, either one blacklists GCC 1=
0,
> or has to specialize pointer_traits there as a workaround (?).

It missed the 10.3 release, but it's on the gcc-10 branch as r10-9698, which
will be in GCC 10.4:
https://gcc.gnu.org/g:32a859531e854382c18abf0b14a306d83f793eb5
That also includes the fix for LWG 3541.=