// check-pass #![feature(const_trait_impl, rustc_attrs)] #[const_trait] trait Foo { #[rustc_do_not_const_check] fn into_iter(&self) { println!("FEAR ME!") } } impl const Foo for () { fn into_iter(&self) { // ^_^ } } const _: () = Foo::into_iter(&()); fn main() {}