error[E0277]: the trait bound `i16: ops::async_function::internal_implementation_detail::AsyncFnKindHelper<i8>` is not satisfied
  --> $DIR/wrong-fn-kind.rs:11:20
   |
LL |       needs_async_fn(async || {
   |  _____--------------_^
   | |     |
   | |     required by a bound introduced by this call
LL | |
LL | |         // FIXME: Should say "closure is `async FnMut` but it needs `async Fn`" or sth.
LL | |         x += 1;
LL | |     });
   | |_____^ the trait `ops::async_function::internal_implementation_detail::AsyncFnKindHelper<i8>` is not implemented for `i16`
   |
note: required by a bound in `needs_async_fn`
  --> $DIR/wrong-fn-kind.rs:8:31
   |
LL |     fn needs_async_fn(_: impl async Fn()) {}
   |                               ^^^^^^^^^^ required by this bound in `needs_async_fn`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0277`.