| use std::fmt; | |
| fn foo() -> Box<impl fmt::Debug+?Sized> { | |
| let x : Box<[u8]> = Box::new([0]); | |
| x | |
| } | |
| fn bar() -> Box<impl fmt::Debug+?Sized> { | |
| let y: Box<dyn fmt::Debug> = Box::new([0]); | |
| y | |
| } | |
| fn main() { | |
| let f = foo(); | |
| let b = bar(); | |
| // this is an `*mut [u8]` in practice | |
| let f_raw : *mut _ = Box::into_raw(f); | |
| // this is an `*mut fmt::Debug` in practice | |
| let mut b_raw = Box::into_raw(b); | |
| // ... and they should not be mixable | |
| b_raw = f_raw as *mut _; //~ ERROR is invalid | |
| } |