なんで(1)はあかんのや？

gistfile1.txt

impl X {
  fn f(&self) -> Y {
  }
}
let x: X;

// (1)
std::thread::spawn(move || {
  let y = x.f();
});

// (2)
let y = x.f();
std::thread::spanw(move || {
  let mut y = y;
|);