// Copyright 2017 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #![feature(optin_builtin_traits)] trait Foo {} impl Foo for .. {} //~^ ERROR The form `impl Foo for .. {}` will be removed, please use `auto trait Foo {}` //~^^ WARN this was previously accepted by the compiler