error[E0120]: the Drop trait may only be implemented on structures --> $DIR/E0117.rs:11:15 | 11 | impl Drop for u32 {} //~ ERROR E0117 | ^^^ implementing Drop requires a struct error[E0117]: only traits defined in the current crate can be implemented for arbitrary types --> $DIR/E0117.rs:11:1 | 11 | impl Drop for u32 {} //~ ERROR E0117 | ^^^^^^^^^^^^^^^^^^^^ impl doesn't use types inside crate | = note: the impl does not reference any types defined in this crate = note: define and implement a trait or new type instead error: aborting due to 2 previous errors