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//! This test checks that opaque types get unsized instead of
//! constraining their hidden type to a trait object.
//@ revisions: next old
//@[next] compile-flags: -Znext-solver
//@[next] check-pass
#![feature(trait_upcasting)]
trait Trait {}
impl Trait for u32 {}
fn hello() -> Box<impl Trait + ?Sized> {
if true {
let x = hello();
let y: Box<dyn Send> = x as Box<dyn Trait + Send>;
//[old]~^ ERROR: the size for values of type `impl Trait + ?Sized` cannot be know
}
Box::new(1u32)
}
fn main() {}
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