Re: [RFC][PATCH 0/5] arch: atomic rework

[Linus Torvalds]

On Sat, Feb 15, 2014 at 9:45 AM, Torvald Riegel <triegel@xxxxxxxxxx> wrote:
>
> I think a major benefit of C11's memory model is that it gives a
> *precise* specification for how a compiler is allowed to optimize.

Clearly it does *not*. This whole discussion is proof of that. It's
not at all clear, and the standard apparently is at least debatably
allowing things that shouldn't be allowed. It's also a whole lot more
complicated than "volatile", so the likelihood of a compiler writer
actually getting it right - even if the standard does - is lower.
They've gotten "volatile" wrong too, after all (particularly in C++).

           Linus
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