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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/109049] std::declval gives wrong result for cv void Date: Tue, 07 Mar 2023 12:32:24 +0000 [thread overview] Message-ID: <bug-109049-4-f5O4tuQaRx@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-109049-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109049 --- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- The reason it behaves this way is that we define declval as: template<typename _Tp> auto declval() noexcept -> decltype(__declval<_Tp>(0)); and decltype(__declval<_Tp>(0)) drops the cv-qualifiers. This implementation is much faster to compile, and so we're not going to stop using it to "fix" the useless testcase in this bug. Nobody cares about decltype(std::declval<const void>) but they do care about compile times.
next prev parent reply other threads:[~2023-03-07 12:32 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-03-07 6:18 [Bug libstdc++/109049] New: " fsb4000 at yandex dot ru 2023-03-07 12:23 ` [Bug libstdc++/109049] " redi at gcc dot gnu.org 2023-03-07 12:32 ` redi at gcc dot gnu.org [this message] 2023-03-07 15:07 ` de34 at live dot cn 2023-03-07 15:43 ` redi at gcc dot gnu.org
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