> > But you should still do the comparison > with a unique C function written for this purpose. > If you tried to use a "convert address to int" function, > you would have a race condition between the conversion > of each address and garbage collection. Or, if all major GCs are compacting and the minor heap is at a higher adress than the major heap, then OCaml's could also preserve the adress order between GC ... How much slower is the compacting major GC comparer to the standard one ? Cheers, Christophe