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From: Florian Weimer <fweimer@redhat.com>
To: Shawn Landden <shawn@git.icu>
Cc: linux-man@vger.kernel.org
Subject: Re: [PATCH] bcmp: note that this function is no longer legacy due to LLVM 9
Date: Fri, 17 Jan 2020 12:57:14 +0100	[thread overview]
Message-ID: <87o8v2pa79.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <20200111145544.5592-1-shawn@git.icu> (Shawn Landden's message of "Sat, 11 Jan 2020 18:55:44 +0400")

* Shawn Landden:

> +This function was deprecated (marked as LEGACY) by POSIX.1-2001).
>  POSIX.1-2008 removes the specification of
>  .BR bcmp ().
> +LLVM 9, released in 2019, revived
> +.BR bcmp ()
> +and generates calls to it instead of
> +.BR memcmp (3)
> +as appropiate as an optimization (as
> +.BR bcmp ()
> +need not traverse memory in-order).
> +.\" http://releases.llvm.org/9.0.0/docs/ReleaseNotes.html#noteworthy-optimizations

This is a pessimation on GNU/Linux if the program uses memcmp as well
because it introduces another relocation.

Thanks,
Florian


  reply	other threads:[~2020-01-17 11:57 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-11 14:55 [PATCH] bcmp: note that this function is no longer legacy due to LLVM 9 Shawn Landden
2020-01-17 11:57 ` Florian Weimer [this message]
  -- strict thread matches above, loose matches on Subject: below --
2020-01-11 14:50 Shawn Landden
2020-01-11 16:11 ` Dmitry V. Levin
2020-01-21 19:52   ` Michael Kerrisk (man-pages)

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