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From: "glenjofe at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/96416] to_address() is broken by static_assert in
 pointer_traits
Date: Mon, 29 Mar 2021 03:08:26 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96416

--- Comment #16 from Glen Joseph Fernandes <glenjofe at gmail dot com> ---
> should a wording defect be raised against std::to_address(Ptr), to state =
that=20
> pointer_traits<Ptr> being well-formed is actually a prerequisite?

That's not an omission in the specification of to_address. The function is
intended for pointers, and specified in terms of checking for a
pointer_traits<P> member, and this means pointer_traits<P> must be well-for=
med.=20

Adding an additional text to the specification saying this explicitly is
unlikely to help anyone. The real change that users of iterators[1] would w=
ant
is to make pointer_traits SFINAE friendly.

[1] Users of pointers don't care much, since all the pointer types people a=
re
using with to_address(p) already have a well-formed pointer_traits<P>.=