ices/101667.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#101667

#![feature(return_position_impl_trait_in_trait)]
#![allow(incomplete_features)]

use core::fmt::Debug;

trait Foo {
    fn baz(&self) -> impl Debug;
}

impl Foo for u32{
    fn baz(&self) -> u32{
        32
    }
}

fn main() {
    let i = Box::new(42_u32) as Box<dyn Foo>;
}

=== stdout ===
=== stderr ===
error[E0038]: the trait `Foo` cannot be made into an object
  --> /home/runner/work/glacier/glacier/ices/101667.rs:17:33
   |
17 |     let i = Box::new(42_u32) as Box<dyn Foo>;
   |                                 ^^^^^^^^^^^^ `Foo` cannot be made into an object
   |
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
  --> /home/runner/work/glacier/glacier/ices/101667.rs:7:8
   |
6  | trait Foo {
   |       --- this trait cannot be made into an object...
7  |     fn baz(&self) -> impl Debug;
   |        ^^^ ...because method `baz` references an `impl Trait` type in its return type
   = help: consider moving `baz` to another trait

error[E0038]: the trait `Foo` cannot be made into an object
  --> /home/runner/work/glacier/glacier/ices/101667.rs:17:13
   |
17 |     let i = Box::new(42_u32) as Box<dyn Foo>;
   |             ^^^^^^^^^^^^^^^^ `Foo` cannot be made into an object
   |
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
  --> /home/runner/work/glacier/glacier/ices/101667.rs:7:8
   |
6  | trait Foo {
   |       --- this trait cannot be made into an object...
7  |     fn baz(&self) -> impl Debug;
   |        ^^^ ...because method `baz` references an `impl Trait` type in its return type
   = help: consider moving `baz` to another trait
   = note: required for `Box<u32>` to implement `CoerceUnsized<Box<dyn Foo>>`
   = note: required by cast to type `Box<dyn Foo>`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0038`.
==============