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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/101761] Random hang with 29_atomics/atomic_ref/wait_notify.cc
Date: Wed, 15 Sep 2021 18:54:08 +0000	[thread overview]
Message-ID: <bug-101761-4-VCrfOjMJ9Z@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-101761-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101761

--- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> ---
My point is that *any* read of aa is undefined while there is an atomic_ref
using it, even in the absence of other threads.

It happens to cause the race you describe, because the value of aa is changing
concurrently. But it's undefined according to the standard even without that.

  parent reply	other threads:[~2021-09-15 18:54 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-03 18:30 [Bug target/101761] New: " hjl.tools at gmail dot com
2021-08-03 18:55 ` [Bug target/101761] " ubizjak at gmail dot com
2021-08-04 15:50 ` ubizjak at gmail dot com
2021-08-04 15:53 ` redi at gcc dot gnu.org
2021-09-08  1:04 ` rodgertq at gcc dot gnu.org
2021-09-15  8:56 ` fw at gcc dot gnu.org
2021-09-15 18:40 ` rodgertq at gcc dot gnu.org
2021-09-15 18:48 ` redi at gcc dot gnu.org
2021-09-15 18:50 ` fw at gcc dot gnu.org
2021-09-15 18:52 ` redi at gcc dot gnu.org
2021-09-15 18:54 ` redi at gcc dot gnu.org [this message]
2021-09-15 18:55 ` redi at gcc dot gnu.org
2021-09-15 18:56 ` rodgertq at gcc dot gnu.org
2021-09-16 19:04 ` redi at gcc dot gnu.org
2021-09-16 21:48 ` cvs-commit at gcc dot gnu.org
2021-10-06 23:41 ` hjl.tools at gmail dot com
2021-10-07  6:45 ` redi at gcc dot gnu.org
2021-10-12 10:59 ` cvs-commit at gcc dot gnu.org
2022-12-28 20:08 ` [Bug testsuite/101761] " pinskia at gcc dot gnu.org

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