Putting a destructor on a newtype struct ICE's if that newtype is an immediate

[pcwalton]

Regression from the change to make newtype structs immediates.

[pcwalton]

Nominating for production ready

[huonw]

Do you have an example? The following compiles with the current stage0 (which is from a few days ago, so definitely has the newtypes-can-be-immediate patch):

struct Foo(uint);

impl Drop for Foo {
    fn drop(&self) {}
}

fn main() {
    let _a = Foo(1);
}

[catamorphism]

Accepted for production-ready

[thestinger]

Closing as a duplicate of #9446. I have a fix in the pipeline for this (#9643).