error[E0733]: recursion in an async block requires boxing
  --> $DIR/indirect-recursion-issue-112047.rs:21:9
   |
LL |         async move { recur(self).await; }
   |         ^^^^^^^^^^   ----------------- recursive call here
   |
note: which leads to this async fn
  --> $DIR/indirect-recursion-issue-112047.rs:13:1
   |
LL | async fn recur(t: impl Recur) {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
LL |     t.recur().await;
   |     --------------- ...leading to this recursive call
   = note: a recursive `async fn` call must introduce indirection such as `Box::pin` to avoid an infinitely sized future

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0733`.