1 use std::cell::UnsafeCell;
2 
main()3 fn main() { unsafe {
4     let c = &UnsafeCell::new(UnsafeCell::new(0));
5     let inner_uniq = &mut *c.get();
6     // stack: [c: SharedReadWrite, inner_uniq: Unique]
7 
8     let inner_shr = &*inner_uniq; // adds a SharedReadWrite
9     // stack: [c: SharedReadWrite, inner_uniq: Unique, inner_shr: SharedReadWrite]
10 
11     *c.get() = UnsafeCell::new(1); // invalidates inner_shr
12     // stack: [c: SharedReadWrite]
13 
14     let _val = *inner_shr.get(); //~ ERROR borrow stack
15 } }
16