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From: Jonathan Wakely <jwakely.gcc@gmail.com>
Date: Mon, 12 Dec 2022 14:48:35 +0000
Message-ID: <CAH6eHdS6S79vdmKnsEKpc2M6OcfpbGz7wSPo9TYW+w3DYf-d4w@mail.gmail.com>
Subject: Re: Missing optimization: mempcpy(3) vs memcpy(3)
To: Alejandro Colomar <alx.manpages@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>, =?UTF-8?Q?Martin_Li=C5=A1ka?= <mliska@suse.cz>, 
	gcc@gcc.gnu.org, GNU C Library <libc-alpha@sourceware.org>
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On Mon, 12 Dec 2022 at 14:09, Alejandro Colomar wrote:
> On 12/12/22 14:56, Jakub Jelinek wrote:

> > I think that is the case, plus the question if one can use a non-standard
> > function to implement a standard function (and if it would be triggered
> > by seeing an expected prototype for the non-standard function).
>
> I guess implementing a standard function by calling a non-standard one is fine.
> The implementation is free to do what it pleases, as long as it provides the
> expected interface.

Even if the program provides a function called mempcpy?