AVR seems to be... in progress. But if we're discussing the inherent properties of a language, not just what happens to be implemented today, the point is whether it's possible with reasonable overhead (e.g. performance, no weird emulation).

High-level blog post: http://dylanmckay.io/blog/rust/avr/llvm/2017/02/09/safer-mic...

Tracking bug on GitHub: https://github.com/rust-lang/rust/issues/42450