rust/tests/ui/coercion/pin-dyn-dispatch-sound.rs

20 lines
552 B
Rust

use std::marker::PhantomPinned;
use std::pin::Pin;
trait MyUnpinTrait {
fn into_pinned_type(self: Pin<&mut Self>) -> Pin<&mut PhantomPinned>;
}
impl MyUnpinTrait for PhantomPinned {
fn into_pinned_type(self: Pin<&mut Self>) -> Pin<&mut PhantomPinned> {
self
}
}
impl Unpin for dyn MyUnpinTrait {} //~ ERROR E0321
// It would be unsound for this function to compile.
fn pin_it(not_yet_pinned: &mut PhantomPinned) -> Pin<&mut PhantomPinned> {
Pin::new(not_yet_pinned as &mut dyn MyUnpinTrait).into_pinned_type()
}
fn main() {}