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From: "de34 at live dot cn" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/111511] Incorrect ADL in std::to_array in GCC
 11/12/13
Date: Thu, 21 Sep 2023 11:37:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111511

--- Comment #5 from Jiang An <de34 at live dot cn> ---
(In reply to m.cencora from comment #2)
> (In reply to Jonathan Wakely from comment #1)
> > (In reply to Jiang An from comment #0)
> > > Not sure whether this should be WONTFIX since the implementation is
> > > fundamentally changed in GCC 14 (PR 110167).
> >=20
> > There's no reason we can't fix the old version in the release branches.
> >=20
> > I did notice this when rewriting it, but I didn't think to change the
> > branches to avoid ADL there, because I plan to backport the new
> > implementation eventually anyway.
>=20
> On a semi-related topic:
> Can't we use __builtin_bit_cast as even simpler implementation of to_array
> for trivial types?

__builtin_bit_cast results in constant evaluation failure when the element =
type
is or contains a pointer or a union, which heavily restricts its usability =
in
to_array.=