If you're interested in the nitty gritty, there's some info in this PR: https://github.com/rust-lang/rust/pull/32756
Though Steve may be talking about some newer work that I haven't heard of yet.
Re:Shipping Rust code in Firefox
by steveklabnik on Tuesday July 12, 2016 @06:27PM
(#12082693)
There's also stuff like this: https://github.com/rust-lang/rust/pull/34789
In general, Jonathan and Niko are working on it :)
Re:Shipping Rust code in Firefox
by moosingin3space on Tuesday July 12, 2016 @06:24PM
(#12082682)
Between Rust's and Elm's error messages, Go's focus on compilation speed, and even GCC's improvements in diagnostics, I'm really enjoying this focus on developer UX I see. It's made me more UX-conscious in my own tools.
The UX of compilers have been improving dramatically lately...