error[E0107]: missing generics for struct `Box` --> $DIR/issue-14092.rs:1:11 | LL | fn fn1(0: Box) {} | ^^^ expected at least 1 generic argument | help: add missing generic argument | LL | fn fn1(0: Box) {} | +++ error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0107`.