src/test/ui/async-await/issue-73137.rs

   1 // Regression test for <https://github.com/rust-lang/rust/issues/73137>
   2
   3 // run-pass
   4 // edition:2018
   5
   6 #![allow(dead_code)]
   7 #![feature(wake_trait)]
   8 use std::future::Future;
   9 use std::task::{Waker, Wake, Context};
  10 use std::sync::Arc;
  11
  12 struct DummyWaker;
  13 impl Wake for DummyWaker {
  14     fn wake(self: Arc<Self>) {}
  15 }
  16
  17 struct Foo {
  18     a: usize,
  19     b: &'static u32,
  20 }
  21
  22 #[inline(never)]
  23 fn nop<T>(_: T) {}
  24
  25 fn main() {
  26     let mut fut = Box::pin(async {
  27         let action = Foo {
  28             b: &42,
  29             a: async { 0 }.await,
  30         };
  31
  32         // An error in the generator transform caused `b` to be overwritten with `a` when `b` was
  33         // borrowed.
  34         nop(&action.b);
  35         assert_ne!(0usize, unsafe { std::mem::transmute(action.b) });
  36
  37         async {}.await;
  38     });
  39     let waker = Waker::from(Arc::new(DummyWaker));
  40     let mut cx = Context::from_waker(&waker);
  41     let _ = fut.as_mut().poll(&mut cx);
  42 }