ICE when using unsafe blocks + UnsafeCell + a move

[jroesch]

This is just some experimentation on my part that triggered an ICE. I may have time to investigate later but for now here is the smallest chunk of code I have and a playground session.

use std::thunk::Thunk;
use std::cell::UnsafeCell;
use std::mem::transmute;

struct Lazy<T> {
    value: UnsafeCell<Option<T>>,
    thunk: UnsafeCell<Option<Thunk<(), T>>>,
}

impl<T> Lazy<T> {
    fn value(&self) -> &T {
        unsafe { 
            let value = self.value.get();
            // deleted some code here
            let raw_value = &(*value).unwrap();
            transmute(raw_value)
        }
    }
}

fn main() {
}

http://is.gd/L2RIMD

[jdm]

Duplicate of #20801.