I've been trying for weeks, every few days, latest servo master and latest incoming branch of rust but I keep on getting rustc compile errors so I must be doing something wrong!

Ubuntu 12.04, this is one that I've been seeing a bit and am getting on today's servo/master & rust/incoming of but it's not the only one I've seen:

rustc  -O -L ../mozjs/ /home/rvagg/git/servo/src/rust-mozjs/js.rc -o js-test --test
/home/rvagg/git/servo/src/rust-mozjs/name_pool.rs:24:12: 24:17 error: expected `;` or `}` after expression but found `c_str`
/home/rvagg/git/servo/src/rust-mozjs/name_pool.rs:24         ret c_str; // ...and so this ptr ought to be valid.

I really want this baby to compile! Suggestions?