Rust language: Use after free? (rustc 0.8)

main.rs

struct Foo {
  x: int
}

impl Drop for Foo {
  fn drop(&mut self) {
    println!("drop {}", self.x);
  }
}

fn main() {
  let mut ptr = ~Foo { x: 0 };

  // This fails to compile:
  //
  //   error: cannot assign to `ptr` because it is borrowed
  //
  // let foo = &ptr;
  // println!("foo.x is {}", foo.x);
  // ptr = ~Foo { x: ptr.x + 1 };
  // println!("foo.x is {}", foo.x);

  // This compiles and runs with the following output:
  //
  //   access 0
  //   drop 0
  //   access 0
  //   drop 1
  //
  // It seems that this is accessing the first object after it is destroyed!
  let test = |foo: &Foo| {
    println!("access {}", foo.x);
    ptr = ~Foo { x: ptr.x + 1 };
    println!("access {}", foo.x);
  };
  test(ptr);
}