// FIXME(compiler-errors): I'm not exactly sure if this is expected to pass or not. // But we fixed an ICE anyways. #![feature(specialization)] #![feature(return_position_impl_trait_in_trait)] #![allow(incomplete_features)] trait Foo { fn bar(&self) -> impl Sized; } default impl Foo for U where U: Copy, { fn bar(&self) -> U { //~^ ERROR method `bar` has an incompatible type for trait *self } } impl Foo for i32 {} fn main() { 1i32.bar(); }