//@ edition:2018 #![feature(type_alias_impl_trait)] struct Bug { V1: [(); { type F = impl core::future::Future; fn concrete_use() -> F { //~^ ERROR to be a future that resolves to `u8`, but it resolves to `()` async {} } let f: F = async { 1 }; //~^ ERROR `async` blocks are not allowed in constants 1 }], } fn main() {}