error[E0369]: cannot add `Box` to `Box` --> $DIR/autoderef-full-lval.rs:15:24 | LL | let z: isize = a.x + b.y; | --- ^ --- Box | | | Box error[E0369]: cannot add `Box` to `Box` --> $DIR/autoderef-full-lval.rs:21:33 | LL | let answer: isize = forty.a + two.a; | ------- ^ ----- Box | | | Box error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0369`.