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pub async fn test() {
    let _ = a([0u8; 1024]).await;
}
#[inline(never)]
pub async fn a<T>(t: T) -> T {
    b(t).await
}
async fn b<T>(t: T) -> T {
    c(t).await
}
async fn c<T>(t: T) -> T {
    t
}

pub fn poll_test() {
    ready_or_panic::block_on(test());
}

mod ready_or_panic {
    use core::future::Future;
    use core::pin::Pin;
    use core::task::{Context, Poll, RawWaker, RawWakerVTable, Waker};

unsafe fn noop_clone(_data: *const ()) -> RawWaker {
        noop_raw_waker()
    }

unsafe fn noop(_data: *const ()) {}

const NOOP_WAKER_VTABLE: RawWakerVTable = RawWakerVTable::new(noop_clone, noop, noop, noop);

const fn noop_raw_waker() -> RawWaker {
        RawWaker::new(core::ptr::null(), &NOOP_WAKER_VTABLE)
    }

#[inline(always)]
    pub fn block_on<O, F: Future<Output = O>>(mut fut: F) -> O {
        let waker = unsafe { Waker::from_raw(noop_raw_waker()) };
        let mut context = Context::from_waker(&waker);
        let pinned = unsafe { Pin::new_unchecked(&mut fut) };
        match pinned.poll(&mut context) {
            Poll::Ready(res) => res,
            _ => {
                panic!("should have been ready")
            }
        }
    }
}