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Subject: Re: [boost] Weak functor: Interested? (How to boost::bind to a weak_ptr)
From: Stewart, Robert (Robert.Stewart_at_[hidden])
Date: 2012-01-11 07:57:02

Roman Perepelitsa wrote:
> It can be done. In fact, it has already been done. See

PMFJI, but that code looks suspect. get_pointer() locks the weak_ptr to get a raw pointer from the related shared_ptr, but then the shared_ptr returned by lock() is allowed to go out of scope. Thus, the ptr_adapter returned by get_pointer() holds a transiently valid raw pointer. By the time the pointer is used to call the member function, the last shared_ptr owning the associated memory could release the memory, so the ptr_adapter will have a dangling pointer.

If ptr_adapter were to hold a shared_ptr instead of a raw pointer, then the memory could not be released out from under the ptr_adapter. That, of course, doesn't work with get_pointer().

Rob Stewart robert.stewart_at_[hidden]
Software Engineer using std::disclaimer;
Dev Tools & Components
Susquehanna International Group, LLP


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