rust/tests/ui/traits/trait-upcasting/migrate-lint-deny.rs
2023-11-20 19:03:47 +00:00

26 lines
436 B
Rust

#![deny(deref_into_dyn_supertrait)]
use std::ops::Deref;
// issue 89190
trait A {}
trait B: A {}
impl<'a> Deref for dyn 'a + B {
//~^ ERROR `dyn B` implements `Deref` with supertrait `A` as target
//~| WARN this will change its meaning in a future release!
type Target = dyn A;
fn deref(&self) -> &Self::Target {
todo!()
}
}
fn take_a(_: &dyn A) {}
fn whoops(b: &dyn B) {
take_a(b)
}
fn main() {}