When the author talks about missing features, is he referring to the new self-hosting compiler only? I remember skimming thru the PDF manual when I first heard about Rust, and I'd find it alarming if stuff like deterministic garbage collection and stack growth have been documented but not actually implemented.
Garbage collection isn't implemented; we're relying on reference counting for now. The self-hosted compiler has no cyclic data structures, so we're fine.
Stack growth was implemented at one point, but we disabled it because the way it was implemented was a proof-of-concept hack (it just rewrote anything that looked like a pointer on the stack). I suspect we're going to switch to a more Go-like model, in which stack growth happens by calling through a stack-switching thunk.
