error[E0507]: cannot move out of `*x` which is behind a shared reference
  --> $DIR/borrowck-fn-in-const-a.rs:6:16
   |
LL |         return *x
   |                ^^ move occurs because `*x` has type `String`, which does not implement the `Copy` trait

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0507`.