// Test that supertraits can't be assumed in impls of // `rustc_specialization_trait`, as such impls would // allow specializing on the supertrait. #![feature(min_specialization)] #![feature(rustc_attrs)] #[rustc_specialization_trait] trait SpecMarker: Default { fn f(); } impl SpecMarker for T { //~^ ERROR cannot specialize fn f() {} } fn main() {}