Messages in this thread | | | Date | Sat, 15 Feb 2014 10:49:11 -0800 | Subject | Re: [RFC][PATCH 0/5] arch: atomic rework | From | Linus Torvalds <> |
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On Sat, Feb 15, 2014 at 9:45 AM, Torvald Riegel <triegel@redhat.com> 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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