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From: Alexander Monakov <amonakov@ispras.ru>
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Subject: Re: Documentation of memcpy and undefined behavior in
 memset
Date: Thu, 6 Jul 2017 20:38:29 +0300 (MSK)
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On Thu, 6 Jul 2017, Rich Felker wrote:

> I'm doubtful of this. Certainly passing a pointer to memcpy with a
> nonzero n is a guarantee that the pointed-to object is non-volatile.
> The n=0 case is less clear though.

My view is that since in n=0 case no memory access inside of memcpy
takes place, the compiler may not deduce that the pointed-to object is
ok for speculative reads.

Alexander