error[E0620]: cast to unsized type: `&{integer}` as `dyn Send` --> $DIR/cast-to-unsized-trait-object-suggestion.rs:2:5 | LL | &1 as dyn Send; | ^^^^^^-------- | | | help: try casting to a reference instead: `&dyn Send` error[E0620]: cast to unsized type: `Box<{integer}>` as `dyn Send` --> $DIR/cast-to-unsized-trait-object-suggestion.rs:3:5 | LL | Box::new(1) as dyn Send; | ^^^^^^^^^^^^^^^-------- | | | help: you can cast to a `Box` instead: `Box` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0620`.