// check-fail #![feature(specialization)] //~^ WARN incomplete trait Family { type Member<'a>: for<'b> PartialEq>; } struct I32Family; impl Family for I32Family { default type Member<'a> = i32; } struct Foo; struct FooFamily; impl Family for FooFamily { default type Member<'a> = Foo; //~^ ERROR can't compare } fn main() {}