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
|
// compile-flags: -Ztrait-solver=next
// check-pass
trait Eq<'a, 'b, T> {}
trait Ambig {}
impl Ambig for () {}
impl<'a, T> Eq<'a, 'a, T> for () where T: Ambig {}
fn eq<'a, 'b, T>(t: T)
where
(): Eq<'a, 'b, T>,
{
}
fn test<'r>() {
let mut x = Default::default();
// When we evaluate `(): Eq<'r, 'r, ?0>` we uniquify the regions.
// That leads us to evaluate `(): Eq<'?0, '?1, ?0>`. The response of this
// will be ambiguous (because `?0: Ambig` is ambig) and also not an "identity"
// response, since the region constraints will contain `'?0 == '?1` (so
// `is_changed` will return true). Since it's both ambig and changed,
// fulfillment will both re-register the goal AND loop again. This hits the
// overflow limit. This should neither be considered overflow, nor ICE.
eq::<'r, 'r, _>(x);
x = ();
}
fn main() {}
|
