error[E0038]: the trait `Expr` is not dyn compatible
  --> $DIR/mentions-Self-in-super-predicates.rs:12:27
   |
LL |     elements: Vec<Box<dyn Expr + 'x>>,
   |                           ^^^^ `Expr` 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/mentions-Self-in-super-predicates.rs:5:21
   |
LL | trait Expr: Debug + PartialEq {
   |       ----          ^^^^^^^^^ ...because it uses `Self` as a type parameter
   |       |
   |       this trait is not dyn compatible...

error[E0038]: the trait `Expr` is not dyn compatible
  --> $DIR/mentions-Self-in-super-predicates.rs:38:20
   |
LL |     let a: Box<dyn Expr> = Box::new(SExpr::new());
   |                    ^^^^ `Expr` 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/mentions-Self-in-super-predicates.rs:5:21
   |
LL | trait Expr: Debug + PartialEq {
   |       ----          ^^^^^^^^^ ...because it uses `Self` as a type parameter
   |       |
   |       this trait is not dyn compatible...

error[E0038]: the trait `Expr` is not dyn compatible
  --> $DIR/mentions-Self-in-super-predicates.rs:40:20
   |
LL |     let b: Box<dyn Expr> = Box::new(SExpr::new());
   |                    ^^^^ `Expr` 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/mentions-Self-in-super-predicates.rs:5:21
   |
LL | trait Expr: Debug + PartialEq {
   |       ----          ^^^^^^^^^ ...because it uses `Self` as a type parameter
   |       |
   |       this trait is not dyn compatible...

error: aborting due to 3 previous errors

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