#![feature(non_lifetime_binders)] //~^ WARN the feature `non_lifetime_binders` is incomplete trait Foo: for Bar {} trait Bar { fn method(&self) {} } fn needs_bar(x: &(impl Bar + ?Sized)) { x.method(); } impl Foo for () {} impl Bar for () {} fn main() { let x: &dyn Foo = &(); //~^ ERROR the trait `Foo` cannot be made into an object //~| ERROR the trait `Foo` cannot be made into an object needs_bar(x); //~^ ERROR the trait `Foo` cannot be made into an object }