Re: [Boost-users] [Thread] barrier destruction after wait() resultsin assertion

Subject: Re: [Boost-users] [Thread] barrier destruction after wait() resultsin assertion
From: Anthony Williams (anthony.ajw_at_[hidden])
Date: 2008-12-03 10:45:31

"Peter Dimov" <pdimov_at_[hidden]> writes:

> Anthony Williams:
> ...
>>> void f()
>>> {
>>>     barrier->wait();
>>> }
>>>
>>> int main(void)
>>> {
>>>     barrier.reset(new boost::barrier(2));
>>>     boost::thread thread(boost::bind(&f));
>>>     barrier->wait();
>>
>> At this point, there is no guarantee that f() has started.
>
> Yes there is.

Doh! Thanks Peter, apparently I'm not thinking straight today.

Anyway, there is no guarantee that the call to wait in f() has
*completed*, which means it might still own the mutex in barrier,
which means it is not safe to destroy the barrier at this point.

Anthony
-- 
Anthony Williams
Author of C++ Concurrency in Action | http://www.manning.com/williams
Custom Software Development | http://www.justsoftwaresolutions.co.uk
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