error[E0038]: the trait `Foo` is not dyn compatible
  --> $DIR/feature-gate-async-fn-in-dyn-trait.rs:7:30
   |
LL | async fn takes_dyn_trait(x: &dyn Foo) {
   |                              ^^^^^^^ `Foo` is not dyn compatible
   |
note: for a trait to be dyn compatible it needs to allow building a vtable
      for more information, visit <https://doc.rust-lang.org/reference/items/traits.html#dyn-compatibility>
  --> $DIR/feature-gate-async-fn-in-dyn-trait.rs:4:14
   |
LL | trait Foo {
   |       --- this trait is not dyn compatible...
LL |     async fn bar(&self);
   |              ^^^ ...because method `bar` is `async`
   = help: consider moving `bar` to another trait

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0038`.