Compiles to a program that segfaults upon execution.

bug.rs

pub enum Thing {
  A(u64),
  B(~Foo)
}

pub trait Foo {
  fn foo();
}

pub struct Struct {
  a: u64
}

impl Foo for Struct {
  pub fn foo() {}
}

pub fn new() -> Thing {
  B(~Struct{a: 5} as ~Foo)
}

fn main() {
  let foo = match new() {
    A(a) => 0,
    B(b) => 1
  };
}