1 #![feature(trait_alias)]
3 trait Foo = std::io::Read + std::io::Write;
6 let _: Box<dyn std::io::Read + std::io::Write>;
7 //~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
9 //~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]