error[E0599]: the method `clone` exists for struct `Box<R>`, but its trait bounds were not satisfied
  --> $DIR/unique-pinned-nocopy.rs:12:16
   |
LL | struct R {
   | -------- doesn't satisfy `R: Clone`
...
LL |     let _j = i.clone();
   |                ^^^^^ method cannot be called on `Box<R>` due to unsatisfied trait bounds
   |
   = note: the following trait bounds were not satisfied:
           `R: Clone`
           which is required by `Box<R>: Clone`
help: consider annotating `R` with `#[derive(Clone)]`
   |
LL + #[derive(Clone)]
LL | struct R {
   |

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0599`.