[marktangotango]

That's understandable. I was mulling over your use of reference counting, and cycle detection with your mark and sweep scheme. Vala has a weak keyword to indicate a non ref counted ownership letting user manage cycles in effect. Otherwise I wonder how useful reference counting is in this case, your vm has the call stack ie the list live root references, as you know. Why not just do mark and sweep? May simplify the code a bit.