Slightly off topic, but is there a good (i.e., fast and easy to use) modern retargetable GC for language prototyping/implementation? I've been looking for something like this for a while, but it seems everyone rolls their own.
But you also want fast, at which point you have to accept that fast gc == complicated and tightly coupled to the implementation details (object layout, type/debug info).
There is no pluggable GC. Conservative GCs (like Boehm GC) come the closest, but they have significant drawbacks (they blindly scan all of memory and can't tell a difference between a pointer and a random number that looks like a pointer, which means scanning&marking phase take longer and they keep objects that could have been freed, which is especially a problem on 32bits, where it's more likely that a random number points inside GC-managed heap).
