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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/64843] miscompilation of atomic_fetch_add on atomic pointer type Date: Wed, 28 Jan 2015 20:38:00 -0000 [thread overview] Message-ID: <bug-64843-4-mIMHmWKJEJ@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-64843-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64843 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |documentation, wrong-code Status|UNCONFIRMED |NEW Last reconfirmed| |2015-01-28 Ever confirmed|0 |1 Known to fail| |5.0 --- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- The documentation indeed suggests this: "These built-in functions perform the operation suggested by the name, and return the value that had previously been in @code{*@var{ptr}}. That is, @smallexample @{ tmp = *ptr; *ptr @var{op}= val; return tmp; @} @end smallexample" thus here *(&p) += 1; Whether the bug is in documentation or code is another question. Confirmed that the testcase produces cited assembly on x86_64 and some older trunk.
next prev parent reply other threads:[~2015-01-28 20:38 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-01-28 19:38 [Bug c/64843] New: " richard-gccbugzilla at metafoo dot co.uk 2015-01-28 20:38 ` rguenth at gcc dot gnu.org [this message] 2015-01-28 21:44 ` [Bug c/64843] " richard-gccbugzilla at metafoo dot co.uk 2015-01-28 23:20 ` joseph at codesourcery dot com 2015-01-28 23:24 ` joseph at codesourcery dot com 2015-01-29 0:05 ` richard-gccbugzilla at metafoo dot co.uk 2015-01-29 1:04 ` redi at gcc dot gnu.org
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