| #![feature(dyn_star, trait_upcasting)] | |
| //~^ WARN the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes | |
| trait A: B {} | |
| trait B {} | |
| impl A for usize {} | |
| impl B for usize {} | |
| fn main() { | |
| let x: Box<dyn* A> = Box::new(1usize as dyn* A); | |
| let y: Box<dyn* B> = x; | |
| //~^ ERROR mismatched types | |
| } |