Something I've wondered about reference counting and optimising compilers: I assume at a lowish level an inlined function call might look something like, p

Something I've wondered about reference counting and optimising compilers: I assume at a lowish level an inlined function call might look something like, pointer->ref_count += 1 obj = pointer->ptr //...do something with obj... pointer->ref_count -= 1 if pointer->ref_count == 0: free(pointer->ptr) Assuming ref_count isn't messed up by another thread (which I guess we're free to do if we haven't put locks around it, or declared it volatile?) then you could optimise away the increment and decrement on `ref_count`, right? I guess I wouldn't be surprised either way. What I'd like to know, though, is whether the `ref_count == 0` check could get optimised away as well. To you and me it's obvious that the count is positive at the start (as a precondition for the pointer access being correct), but I can't really see how an optimising compiler could know that.