rust/tests/ui/regions/regions-trait-variance.rs
2023-01-11 09:32:08 +00:00

45 lines
581 B
Rust

// Issue #12470.
trait X {
fn get_i(&self) -> isize;
}
struct B {
i: isize
}
impl X for B {
fn get_i(&self) -> isize {
self.i
}
}
impl Drop for B {
fn drop(&mut self) {
println!("drop");
}
}
struct A<'r> {
p: &'r (dyn X + 'r)
}
fn make_a(p: &dyn X) -> A {
A{p:p}
}
fn make_make_a<'a>() -> A<'a> {
let b: Box<B> = Box::new(B {
i: 1,
});
let bb: &B = &*b;
make_a(bb) //~ ERROR cannot return value referencing local data `*b`
}
fn main() {
let a = make_make_a();
println!("{}", a.p.get_i());
}