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From: Alexander Terekhov <terekhov@web.de>
Newsgroups: comp.programming.threads
Subject: Re: forcing the compiler to reload from memory with c++0x
Date: Fri, 28 Jan 2011 14:39:20 +0100
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David Jobet wrote:
> 
> Alexander Terekhov wrote:
> 
> > initial thread: x = y = 0:
> >
> > thread A: if (x) y = x;
> >
> > thread B: if (y) x = y;
> >
> > The final outcome (x | y) != 0 is prohibited without any atomics and its
> > memory ordering.
> >
> > I call that an implied code-conditional hoist-store barrier constraint.
> 
> Hello Alexander,
> 
> I though we needed a memory model precisely because the current spec does
> not say anything about threads !
> Since your example is about program correctness in presence of thread, and
> our current spec does not say anything about thread, can you elaborate ?

I meant C++0x. Under C++0x the example above is valid and has no data
races.

regards,
alexander.