error[E0728]: `await` is only allowed inside `async` functions and blocks --> $DIR/issue-62009-2.rs:8:22 | LL | fn main() { | ---- this is not `async` LL | (async || 2333)().await; | ^^^^^^ only allowed inside `async` functions and blocks error: aborting due to previous error For more information about this error, try `rustc --explain E0728`.