Re: [Boost-users] [weak_ptr] thread safe?

From: Peter Dimov (pdimov_at_[hidden])
Date: 2006-04-19 17:08:32

Alain Cormier wrote:
> So, can I conclude that it is a bad behavior in boost::weak_ptr? For
> now, I have simply changed add_ref_lock to :
>
> long tmp2 = tmp + 1;
> if(InterlockedCompareExchange ( &use_count_, tmp2, tmp ) == tmp2 - 1 )
> return true;
>
> This way, VC6 doesn't optimise the return value of
> InterlockedCompareExchange and the disassembly looks ok. Can I expect
> this workaround (or any better) in boost in a near future so that
> weak_ptr truly work with VC6 in release and multi-threaded
> environment?

I have applied your fix. It will be included in the upcoming release 1.34. 
Thanks for the report!