error[E0277]: the trait bound `(): std::error::Error` is not satisfied --> $DIR/coerce-issue-49593-box-never-windows.rs:18:53 | LL | /* *mut $0 is coerced to Box here */ Box::<_ /* ! */>::new(x) | ^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::error::Error` is not implemented for `()` | = note: required for the cast from `Box<()>` to `Box<(dyn std::error::Error + 'static)>` error[E0277]: the trait bound `(): std::error::Error` is not satisfied --> $DIR/coerce-issue-49593-box-never-windows.rs:23:49 | LL | /* *mut $0 is coerced to *mut Error here */ raw_ptr_box::<_ /* ! */>(x) | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::error::Error` is not implemented for `()` | = note: required for the cast from `*mut ()` to `*mut (dyn std::error::Error + 'static)` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0277`.