[Omp] OpenMP spec 2.5 seems to have incorrect flush example on page 12

[Greg Bronevetsky]

> The point is simply that _unsophisticated_ users should be aware that
> writing code with explicit flushes is difficult to get right.  They
> should understand that they run the risk of implanting complex bugs in
> their code.  And not only that - as we've seen in this thread, they
> should beware of asking the compiler to do aggressive optimizations on
> such code, because sometimes those optimizations may be unsafe in the
> presence of explicit flushes.
> 
   I disagree that explicit flushes are the problem here. We get the same
problem all OpenMP synchronization constructs given this particular
compiler optimization. I think that most OpenMP people would want to
forbid this optimization but I'd like to see some more people give their
thumbs up or down.

                             Greg Bronevetsky