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Date: Wed, 05 Oct 2011 20:12:00 -0000
From: Andrew MacLeod <amacleod@redhat.com>
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To: Jeffrey Yasskin <jyasskin@google.com>
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Subject: Re: C++11 atomic library notes
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On 10/05/2011 10:44 AM, Jeffrey Yasskin wrote:
>
> Yes, that's what I'm suggesting. The rule for 'volatile' from the
> language is just that "Accesses to volatile objects are evaluated
> strictly according to the rules of the abstract machine." If the
> instruction-level implementation for a 16-byte atomic load is
> cmpxchg16b, then that's just how the abstract machine is implemented,
> and the rule says you have to do that consistently for volatile
> objects rather than sometimes optimizing it away. That's my argument
> anyway. If there's another standard you're following beyond "kernel
> people tend to ask for it," the situation may be trickier.

perfect, I like it.
Andrew