uj:

I would appreciate if someone could have a look at it and tell me if there's something wrong with my approach.

class IntrusiveCount { // thread-safe base class to enable derived class for use with the Boost intrusive smart pointer
public:
...//skipped when quoting
   friend void intrusive_ptr_release(IntrusiveCount* p) {
      if (p->ref_count.fetch_and_add(-1) == 1) delete p; // decrement counter. If it was 1 before it's 0 now so delete
   }
...//skipped when quoting
private:
   IntrusiveCount(const IntrusiveCount&);
   tbb::atomic<int> ref_count;
};

I had to change the counter to an int (from short) otherwise I get this level 2 warning on VS2008 standard,

C:UsersadminDocumentsMint	bbsrcinclude	bbatomic.h(157) : warning C4244: 'argument' : 
conversion from 'tbb::internal::atomic_traits<Size,M>::word' to 'short', possible loss of data

You did it almost right, except for one thing. tbb::atomic<>::fetch_and_add returns the value before the atomic addition, i.e. it is equivalent to a postfix increment, while the original code used a prefix increment.

In fact, you do not need to use fetch_and_add at all, because tbb::atomic<> overloads increment and decrement operators, in both postix and prefix forms. So the only change in the original code would be in the declaration of ref_count as tbb::atomic<int>.

By the way, which TBB package did you use? I wonder about this VS2008 warning. I believe our tests would show it; so most probably, it has been fixed in latest updates of TBB.