Possibly a dup of #17359. Minimal example to reproduce in play.rust-lang.org as of 10/2/2013: ``` #![feature(associated_types)] trait Person { type string; } struct Someone<P: Person>; fn main() { } <anon>:6:19: 6:25 error: internal compiler error: find_associated_type_in_generics(): didn't find associated type anywhere in the generics list <anon>:6 struct Someone<P: Person>; ^~~~~~ ```