error[E0277]: the trait bound `(): CoerceUnsized<*const [u8]>` is not satisfied
  --> $DIR/issue-44861.rs:21:26
   |
LL |     default type Data2 = ();
   |                          ^^ the trait `CoerceUnsized<*const [u8]>` is not implemented for `()`
   |
note: required by a bound in `Smartass::Data2`
  --> $DIR/issue-44861.rs:12:17
   |
LL |     type Data2: CoerceUnsized<*const [u8]>;
   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Smartass::Data2`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0277`.