// Check that supertraits cannot be used to work around min_specialization // limitations. #![feature(min_specialization)] #![feature(rustc_attrs)] trait HasMethod { fn method(&self); } #[rustc_unsafe_specialization_marker] trait Marker: HasMethod {} trait Spec { fn spec_me(&self); } impl Spec for T { default fn spec_me(&self) {} } impl Spec for T { //~^ ERROR cannot specialize on trait `HasMethod` fn spec_me(&self) { self.method(); } } fn main() {}