[gclist] Guardians to finalize objects

[Giuliano Carlini]

Guardians in a Generation-Based Garbage Collector.
R. Kent Dybvig, Carl Bruggeman, and David Eby.
ACM PLDI '93
pg 207 to 216.

You can get it from http://www.cs.indiana.edu/proglang/papers/guardians.ps

If your interested in finalization issues you'll want to read
this paper.

It handles finalization order, reanimation, and mutator semantics
very cleanly. It's cheap to implement. And, it doesn't succumb to
the billion dollars in a billion years problem.

It may require minor tweaks to the GC. Or, maybe not. I think it
can be done using finalizers that run unordered but that
reanimate.

g