| // run-pass | |
| #![allow(unreachable_code)] | |
| // Regression test for #39808. The type parameter of `Owned` was | |
| // considered to be "unconstrained" because the type resulting from | |
| // `format!` (`String`) was not being propagated upward, owing to the | |
| // fact that the expression diverges. | |
| use std::borrow::Cow; | |
| fn main() { | |
| let _ = if false { | |
| Cow::Owned(format!("{:?}", panic!())) | |
| } else { | |
| Cow::Borrowed("") | |
| }; | |
| } |