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From: "mpolacek at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/113064] assignement from temporary sometimes invokes copy-assign instead of move-assign operator
Date: Tue, 19 Dec 2023 15:54:36 +0000 [thread overview]
Message-ID: <bug-113064-4-zCnA0BQucx@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113064-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113064
--- Comment #6 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
(In reply to m.cencora from comment #4)
> This also might be a just another symptom of the same root cause:
>
> struct bar
> {
> bar() = default;
>
> bar(const bar&);
> bar(bar&&);
>
> bar& operator=(const bar&);
> bar& operator=(bar&&);
> };
>
> struct foo
> {
> operator const bar& () const &;
>
> operator bar& () &;
>
> operator bar&&() &&;
> };
>
> void test()
> {
> bar a = foo{}; // ok
>
> a = foo{}; // not ok - ambiguous call, but why? &&-qualified looks like
> a better match
>
> foo f;
> a = f; // ok
>
> a = static_cast<const foo&>(foo{}); // ok
> }
Here the error showed up in r9-6486:
commit c7e936dbc7f59ad09c28ef57e5399a4256061747
Author: Jason Merrill <jason@redhat.com>
Date: Mon Mar 11 23:19:22 2019 -0400
PR c++/86521 - wrong overload resolution with ref-qualifiers.
Here we were wrongly treating binding a const lvalue ref to an xvalue as
direct binding, which is wrong under [dcl.init.ref] and [over.match.ref].
next prev parent reply other threads:[~2023-12-19 15:54 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-18 12:04 [Bug c++/113064] New: " m.cencora at gmail dot com
2023-12-18 12:41 ` [Bug c++/113064] " m.cencora at gmail dot com
2023-12-18 13:00 ` m.cencora at gmail dot com
2023-12-18 19:58 ` mpolacek at gcc dot gnu.org
2023-12-19 9:10 ` m.cencora at gmail dot com
2023-12-19 11:39 ` m.cencora at gmail dot com
2023-12-19 15:54 ` mpolacek at gcc dot gnu.org [this message]
2024-01-03 20:43 ` cvs-commit at gcc dot gnu.org
2024-01-03 22:35 ` ppalka at gcc dot gnu.org
2024-01-03 22:36 ` ppalka at gcc dot gnu.org
2024-01-03 22:50 ` ppalka at gcc dot gnu.org
2024-01-04 8:24 ` m.cencora at gmail dot com
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