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// ex-ice: #141409
//@ compile-flags: -Zmir-enable-passes=+Inline -Zvalidate-mir -Zlint-mir --crate-type lib
//@ edition:2024
//@ check-pass
#![feature(async_drop)]
#![allow(incomplete_features)]
#![allow(non_snake_case)]
use std::mem::ManuallyDrop;
use std::{
future::{async_drop_in_place, Future},
pin::{pin, Pin},
sync::{mpsc, Arc},
task::{Context, Poll, Wake, Waker},
};
fn main() {
block_on(bar(0))
}
async fn baz(ident_base: usize) {}
async fn bar(ident_base: usize) {
baz(1).await
}
fn block_on<F>(fut_unpin: F) -> F::Output
where
F: Future,
{
let fut_pin = pin!(ManuallyDrop::new(fut_unpin));
let mut fut = unsafe { Pin::map_unchecked_mut(fut_pin, |x| &mut **x) };
let (waker, rx) = simple_waker();
let mut context = Context::from_waker(&waker);
let rv = loop {
match fut.as_mut().poll(&mut context) {
Poll::Ready(out) => break out,
PollPending => (),
}
};
let drop_fut_unpin = unsafe { async_drop_in_place(fut.get_unchecked_mut()) };
let drop_fut = pin!(drop_fut_unpin);
loop {
match drop_fut.poll(&mut context) {
Poll => break,
}
}
rv
}
fn simple_waker() -> (Waker, mpsc::Receiver<()>) {
struct SimpleWaker {
tx: mpsc::Sender<()>,
}
impl Wake for SimpleWaker {
fn wake(self: Arc<Self>) {}
}
let (tx, rx) = mpsc::channel();
(Waker::from(Arc::new(SimpleWaker { tx })), rx)
}
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