error[E0507]: cannot move out of `y`, a captured variable in an `Fn` closure
  --> $DIR/unboxed-closures-move-upvar-from-non-once-ref-closure.rs:12:9
   |
LL |     let y = vec![format!("World")];
   |         - captured outer variable
LL |     call(|| {
   |          -- captured by this `Fn` closure
LL |         y.into_iter();
   |         ^ ----------- `y` moved due to this method call
   |         |
   |         move occurs because `y` has type `Vec<String>`, which does not implement the `Copy` trait
   |
note: `into_iter` takes ownership of the receiver `self`, which moves `y`
  --> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
help: you can `clone` the value and consume it, but this might not be your desired behavior
   |
LL |         <Vec<String> as Clone>::clone(&y).into_iter();
   |         +++++++++++++++++++++++++++++++ +
help: consider cloning the value if the performance cost is acceptable
   |
LL |         y.clone().into_iter();
   |          ++++++++

error: aborting due to 1 previous error

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