error[E0620]: cast to unsized type: `&[usize; 2]` as `[usize]` --> $DIR/issue-17441.rs:2:16 | LL | let _foo = &[1_usize, 2] as [usize]; | ^^^^^^^^^^^^^^^^^------- | | | help: try casting to a reference instead: `&[usize]` error[E0620]: cast to unsized type: `Box` as `dyn Debug` --> $DIR/issue-17441.rs:5:16 | LL | let _bar = Box::new(1_usize) as dyn std::fmt::Debug; | ^^^^^^^^^^^^^^^^^^^^^------------------- | | | help: you can cast to a `Box` instead: `Box` error[E0620]: cast to unsized type: `usize` as `dyn Debug` --> $DIR/issue-17441.rs:8:16 | LL | let _baz = 1_usize as dyn std::fmt::Debug; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | help: consider using a box or reference as appropriate --> $DIR/issue-17441.rs:8:16 | LL | let _baz = 1_usize as dyn std::fmt::Debug; | ^^^^^^^ error[E0620]: cast to unsized type: `[usize; 2]` as `[usize]` --> $DIR/issue-17441.rs:11:17 | LL | let _quux = [1_usize, 2] as [usize]; | ^^^^^^^^^^^^^^^^^^^^^^^ | help: consider using a box or reference as appropriate --> $DIR/issue-17441.rs:11:17 | LL | let _quux = [1_usize, 2] as [usize]; | ^^^^^^^^^^^^ error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0620`.