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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/109945] Escape analysis hates copy elision: different result with -O1 vs -O2
Date: Tue, 20 Feb 2024 16:49:03 +0000	[thread overview]
Message-ID: <bug-109945-4-5OaK78IRoN@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-109945-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109945

--- Comment #32 from Jonathan Wakely <redi at gcc dot gnu.org> ---
[basic.stc.general] says global == &w is implementation-defined if global is an
invalid pointer value, not just unspecified. GCC could define it to be
unspecified, or UB, and even say "it's UB just in this one case where the
address was a temporary created under the permission granted by
[class.temporary] p3" (although I don't think we do define it that way, we just
compare the bits).

  parent reply	other threads:[~2024-02-20 16:49 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-23 14:00 [Bug c++/109945] New: " arthur.j.odwyer at gmail dot com
2023-05-23 16:09 ` [Bug tree-optimization/109945] " rguenth at gcc dot gnu.org
2023-05-23 16:11 ` rguenth at gcc dot gnu.org
2023-05-23 16:19 ` pinskia at gcc dot gnu.org
2023-05-23 16:48 ` rguenth at gcc dot gnu.org
2023-05-23 16:53 ` rguenth at gcc dot gnu.org
2023-05-23 16:53 ` pinskia at gcc dot gnu.org
2023-05-23 17:46 ` arthur.j.odwyer at gmail dot com
2023-05-23 17:49 ` pinskia at gcc dot gnu.org
2023-05-23 17:52 ` pinskia at gcc dot gnu.org
2023-05-23 17:53 ` pinskia at gcc dot gnu.org
2023-05-23 19:38 ` arthur.j.odwyer at gmail dot com
2023-05-24  6:48 ` rguenth at gcc dot gnu.org
2023-05-24  7:59 ` rguenth at gcc dot gnu.org
2023-05-24  8:16 ` jakub at gcc dot gnu.org
2023-05-24  8:42 ` rguenther at suse dot de
2023-05-24  8:51 ` jakub at gcc dot gnu.org
2023-05-24  8:55 ` rguenther at suse dot de
2023-05-24  9:00 ` jakub at gcc dot gnu.org
2023-05-24 10:12 ` rguenth at gcc dot gnu.org
2023-07-01 23:37 ` pinskia at gcc dot gnu.org
2023-07-10  8:52 ` rguenth at gcc dot gnu.org
2024-02-20  9:58 ` rguenth at gcc dot gnu.org
2024-02-20 10:45 ` jakub at gcc dot gnu.org
2024-02-20 11:53 ` jakub at gcc dot gnu.org
2024-02-20 12:07 ` redi at gcc dot gnu.org
2024-02-20 12:15 ` redi at gcc dot gnu.org
2024-02-20 12:33 ` rguenth at gcc dot gnu.org
2024-02-20 12:41 ` redi at gcc dot gnu.org
2024-02-20 12:48 ` jakub at gcc dot gnu.org
2024-02-20 15:47 ` arthur.j.odwyer at gmail dot com
2024-02-20 15:52 ` arthur.j.odwyer at gmail dot com
2024-02-20 16:49 ` redi at gcc dot gnu.org [this message]
2024-03-01 17:20 ` redi at gcc dot gnu.org

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