error[E0435]: attempt to use a non-constant value in a constant --> $DIR/issue-3668.rs:8:34 | LL | static childVal: Box

= self.child.get(); | --------------- ^^^^ non-constant value | | | help: consider using `let` instead of `static`: `let childVal` error: aborting due to previous error For more information about this error, try `rustc --explain E0435`.