C ++ volatile required when rotating on boost :: shared_ptr operator bool ()?

Question

Possible duplicate:
When to use volatile with multiple threads?

I have two threads referencing the same one boost::shared_ptr:

boost::shared_ptr<Widget> shared;

The thread rotates, expecting another thread to reset boost::shared_ptr:

while(shared)
   boost::thread::yield();

And at some point another thread will call:

shared.reset();

My question is, do I need to declare a generic pointer how volatileto prevent the compiler from optimizing the call shared.operator bool()from the loop and never detect changes? I know that if I just looped on a variable, waiting until it reaches 0, I would need it volatile, but I'm not sure that it is boost::shared_ptrimplemented in such a way that it is not needed here.

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Answer 1

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Answer 2

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