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From: "nyh at math dot technion.ac.il" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/108296] __builtin_memcpy generating wrong code in some cases
Date: Thu, 05 Jan 2023 09:08:16 +0000	[thread overview]
Message-ID: <bug-108296-4-5gZNB77bNd@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108296-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108296

--- Comment #2 from Nadav Har'El <nyh at math dot technion.ac.il> ---
Thanks. Interesting. So __builtin_memcpy() is simply not supposed to work
correctly for overlapping areas? I now realize that according to memcpy(3)
documentation, memcpy() is also not guaranteed to work correctly in this case
(and you should use memmove() in this case), but in practice it does work
correctly when copying a higher address to a lower address.

  parent reply	other threads:[~2023-01-05  9:08 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-05  8:37 [Bug c/108296] New: " nyh at math dot technion.ac.il
2023-01-05  8:53 ` [Bug c/108296] " pinskia at gcc dot gnu.org
2023-01-05  9:08 ` nyh at math dot technion.ac.il [this message]
2023-01-05 11:10 ` jakub at gcc dot gnu.org
2023-01-05 11:14 ` jakub at gcc dot gnu.org
2023-01-09 11:15 ` rguenth at gcc dot gnu.org

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