| error[E0277]: `std::rc::Rc<std::cell::RefCell<A>>` cannot be sent between threads safely |
| --> $DIR/issue-7013.rs:26:19 |
| | |
| LL | let a = A {v: box B{v: None} as Box<dyn Foo + Send>}; |
| | ^^^^^^^^^^^^^^ `std::rc::Rc<std::cell::RefCell<A>>` cannot be sent between threads safely |
| | |
| = help: within `B`, the trait `std::marker::Send` is not implemented for `std::rc::Rc<std::cell::RefCell<A>>` |
| = note: required because it appears within the type `std::option::Option<std::rc::Rc<std::cell::RefCell<A>>>` |
| = note: required because it appears within the type `B` |
| = note: required for the cast to the object type `dyn Foo + std::marker::Send` |
| |
| error: aborting due to previous error |
| |
| For more information about this error, try `rustc --explain E0277`. |
