error[E0072]: recursive type `ElemDerived` has infinite size --> $DIR/issue-72554.rs:4:1 | LL | pub enum ElemDerived { | ^^^^^^^^^^^^^^^^^^^^ LL | LL | A(ElemDerived) | ----------- recursive without indirection | help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle | LL | A(Box) | ++++ + error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0072`.