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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/108393] circular concept false-positive
Date: Fri, 13 Jan 2023 16:09:08 +0000	[thread overview]
Message-ID: <bug-108393-4-ASE97zeUwe@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108393-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108393

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The concept C checks whether S<unreachable_sentinel_t> satisfies the constraint
for the iterator_traits specialization. That performs ADL for operator== with
S<unreachable_sentinel_t> and unreachable_sentinel_t as associated classes.
That finds the hidden friend function, and then performs overload resolution to
see if it's viable for S<unreachable_sentinel_t> arguments. Overload resolution
checks whether the arguments satisfy the constraints, which means checking if C
is satisfied, which creates the cycle.

The question is whether GCC is correct to check constraint satisfaction for one
argument when the other argument cannot be converted to unreachable_sentinel_t.

  reply	other threads:[~2023-01-13 16:09 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-13 13:58 [Bug c++/108393] New: " nikolasklauser at berlin dot de
2023-01-13 16:09 ` redi at gcc dot gnu.org [this message]
2023-01-13 16:15 ` [Bug c++/108393] " redi at gcc dot gnu.org
2023-01-13 16:28 ` ppalka at gcc dot gnu.org
2023-01-27 17:02 ` pinskia at gcc dot gnu.org
2023-05-19  3:34 ` pinskia at gcc dot gnu.org
2024-03-09 15:37 ` ppalka at gcc dot gnu.org

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