[gclist] ref-counting performance cost

[Laurent Guerby]

> _Every_ ref counter I've ever come into contact with
> requires a GC to back it up.

Note that if you create only immutable objects (an often overlooked
technique IMHO), the ref counter is enough because you can't create
cycles between objects. 

The software I develop at work (> 100KSLOC of Ada 95 for financial
computations) uses this combination for memory management.

-- 
Laurent Guerby <guerby@acm.org>