mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-22 14:55:26 +00:00
15 lines
491 B
Rust
15 lines
491 B
Rust
trait Super {}
|
|
trait Sub: Super {}
|
|
|
|
struct Wrapper<T: ?Sized>(T);
|
|
|
|
// This cast should not compile.
|
|
// Upcasting can't work here, because we are also changing the type (`Wrapper`),
|
|
// and reinterpreting would be confusing/surprising.
|
|
// See <https://github.com/rust-lang/rust/pull/120248#discussion_r1487739518>
|
|
fn cast(ptr: *const dyn Sub) -> *const Wrapper<dyn Super> {
|
|
ptr as _ //~ error: casting `*const (dyn Sub + 'static)` as `*const Wrapper<dyn Super>` is invalid
|
|
}
|
|
|
|
fn main() {}
|