> Maybe someone else can confirm, but I think right now Rust can't cross-compile; I would hope that this changes after 1.0, as LLVM makes it fairly easy to do.

Rust can cross-compile, at least for a limited set of targets (see https://github.com/npryce/rusty-pi/blob/master/doc/compile-t... for an example)

The main pain point for the moment is that you need to build the cross-compiler yourself (which takes a while), and since the language changes every week, you have to recompile the cross-compiler every time.