tests/ui/async-await/dyn/wrong-size.rs


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

//@ edition: 2021

#![feature(async_fn_in_dyn_trait)]
//~^ WARN the feature `async_fn_in_dyn_trait` is incomplete

use std::future::Future;

trait AsyncTrait {
    async fn async_dispatch(&self);
}

impl AsyncTrait for &'static str {
    fn async_dispatch(&self) -> impl Future<Output = ()> {
        async move {
            // The implementor must box the future...
        }
    }
}

fn main() {
    let x: &dyn AsyncTrait = &"hello, world!";
    //~^ ERROR `impl Future<Output = ()>` needs to have the same ABI as a pointer
}