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From: "post+sourceware.org at ralfj dot de" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug string/31055] Request: guarantee that memcpy(x, x, n) is well-defined
Date: Thu, 23 Nov 2023 15:18:50 +0000	[thread overview]
Message-ID: <bug-31055-131-4sxgA1WR4v@http.sourceware.org/bugzilla/> (raw)
In-Reply-To: <bug-31055-131@http.sourceware.org/bugzilla/>

https://sourceware.org/bugzilla/show_bug.cgi?id=31055

--- Comment #6 from Ralf Jung <post+sourceware.org at ralfj dot de> ---
I didn't know there's a "restrict" in the signature of this function even in
the C standard.

Yes that would have to be removed to make memcpy(x, x, n) well-defined. But if
there are no benefits from having the restrict there (which can be determined
by checking if the generated assembly changes, or by benchmarking), then
there's no point in having it in the first place.

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  parent reply	other threads:[~2023-11-23 15:18 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-11 17:37 [Bug string/31055] New: " post+sourceware.org at ralfj dot de
2023-11-11 18:41 ` [Bug string/31055] " sam at gentoo dot org
2023-11-13 18:47 ` adhemerval.zanella at linaro dot org
2023-11-18 17:56 ` post+sourceware.org at ralfj dot de
2023-11-21 15:30 ` adhemerval.zanella at linaro dot org
2023-11-23  7:36 ` post+sourceware.org at ralfj dot de
2023-11-23 11:53 ` adhemerval.zanella at linaro dot org
2023-11-23 14:48 ` sam at gentoo dot org
2023-11-23 15:18 ` post+sourceware.org at ralfj dot de [this message]
2023-11-24  7:46 ` rguenth at gcc dot gnu.org
2023-11-24  8:52 ` post+sourceware.org at ralfj dot de
2023-11-24  9:37 ` rguenth at gcc dot gnu.org
2023-11-28  7:18 ` sam at gentoo dot org

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