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Re: forcing the compiler to reload from memory with c++0x

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Andy Venikov <swojchelowek@gmail.com> writes:

> atomic<int> a_int;
> ...
> while (!a_int.get(mode_acquire))
> {
> }
>
> As understand, in this case the compiler in *NOT* allowed to optimize
> the loop away. Am I wrong?

This doesn't actually impose any additional restrictions over
memory_order_relaxed unless the load actually reads a value written by
another thread with memory_order_release (or equivalent) on the store.

Anthony
-- 
Author of C++ Concurrency in Action     http://www.stdthread.co.uk/book/
just::thread C++0x thread library             http://www.stdthread.co.uk
Just Software Solutions Ltd       http://www.justsoftwaresolutions.co.uk
15 Carrallack Mews, St Just, Cornwall, TR19 7UL, UK. Company No. 5478976

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Re: forcing the compiler to reload from memory with c++0x Andy Venikov <swojchelowek@gmail.com> - 2011-01-28 16:44 -0500
  Re: forcing the compiler to reload from memory with c++0x Anthony Williams <anthony.ajw@gmail.com> - 2011-01-30 22:00 +0000
  Re: forcing the compiler to reload from memory with c++0x Andy Venikov <swojchelowek@gmail.com> - 2011-01-31 14:28 -0500
  Re: forcing the compiler to reload from memory with c++0x Dmitriy Vyukov <dvyukov@gmail.com> - 2011-01-29 01:47 -0800

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