diff options
Diffstat (limited to 'tests/ui/async-await/async-is-unwindsafe.rs')
-rw-r--r-- | tests/ui/async-await/async-is-unwindsafe.rs | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tests/ui/async-await/async-is-unwindsafe.rs b/tests/ui/async-await/async-is-unwindsafe.rs new file mode 100644 index 000000000..56ed28472 --- /dev/null +++ b/tests/ui/async-await/async-is-unwindsafe.rs @@ -0,0 +1,30 @@ +// edition:2018 + +fn is_unwindsafe(_: impl std::panic::UnwindSafe) {} + +fn main() { + // A normal future created by an async block takes a `&mut Context<'_>` argument. + // That should not leak through to the whole async block. + is_unwindsafe(async { + async {}.await; // this needs an inner await point + }); + + is_unwindsafe(async { + //~^ ERROR the type `&mut Context<'_>` may not be safely transferred across an unwind boundary + use std::ptr::null; + use std::task::{Context, RawWaker, RawWakerVTable, Waker}; + let waker = unsafe { + Waker::from_raw(RawWaker::new( + null(), + &RawWakerVTable::new(|_| todo!(), |_| todo!(), |_| todo!(), |_| todo!()), + )) + }; + let mut cx = Context::from_waker(&waker); + let cx_ref = &mut cx; + + async {}.await; // this needs an inner await point + + // in this case, `&mut Context<'_>` is *truly* alive across an await point + drop(cx_ref); + }); +} |