1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
// Check that we aren't using unsound specialization in slice comparisons.
// run-pass
use std::cell::Cell;
use std::cmp::Ordering;
struct Evil<'a, 'b>(Cell<(&'a [i32], &'b [i32])>);
impl PartialEq for Evil<'_, '_> {
fn eq(&self, _other: &Self) -> bool {
true
}
}
impl Eq for Evil<'_, '_> {}
impl PartialOrd for Evil<'_, '_> {
fn partial_cmp(&self, _other: &Self) -> Option<Ordering> {
Some(Ordering::Equal)
}
}
impl<'a> Ord for Evil<'a, 'a> {
fn cmp(&self, _other: &Self) -> Ordering {
let (a, b) = self.0.get();
self.0.set((b, a));
Ordering::Equal
}
}
fn main() {
let x = &[1, 2, 3, 4];
let u = {
let a = Box::new([7, 8, 9, 10]);
let y = [Evil(Cell::new((x, &*a)))];
let _ = &y[..] <= &y[..];
let [Evil(c)] = y;
c.get().0
};
assert_eq!(u, &[1, 2, 3, 4]);
}
|
