// build-pass #![crate_type = "lib"] #![feature(staged_api)] #![feature(const_trait_impl)] #![stable(feature = "foo", since = "1.0.0")] #[stable(feature = "potato", since = "1.27.0")] pub struct Data { _data: u128 } #[stable(feature = "potato", since = "1.27.0")] impl const Default for Data { #[rustc_const_unstable(feature = "data_foo", issue = "none")] fn default() -> Data { Data { _data: 42 } } }