1 mod safe {
2     use std::slice::from_raw_parts_mut;
3 
split_at_mut<T>(self_: &mut [T], mid: usize) -> (&mut [T], &mut [T])4     pub fn split_at_mut<T>(self_: &mut [T], mid: usize) -> (&mut [T], &mut [T]) {
5         let len = self_.len();
6         let ptr = self_.as_mut_ptr();
7 
8         unsafe {
9             assert!(mid <= len);
10 
11             (from_raw_parts_mut(ptr, len - mid), // BUG: should be "mid" instead of "len - mid"
12             from_raw_parts_mut(ptr.offset(mid as isize), len - mid))
13         }
14     }
15 }
16 
main()17 fn main() {
18     let mut array = [1,2,3,4];
19     let (a, b) = safe::split_at_mut(&mut array, 0);
20     //~^ ERROR borrow stack
21     a[1] = 5;
22     b[1] = 6;
23 }
24