error[E0072]: recursive type `Bar` has infinite size --> $DIR/issue-17431-5.rs:5:1 | LL | struct Bar { x: Bar , marker: marker::PhantomData } | ^^^^^^^^^^^^^ -------- recursive without indirection | help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle | LL | struct Bar { x: Box> , marker: marker::PhantomData } | ++++ + error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0072`.