error[E0277]: the type `std::cell::UnsafeCell<i32>` may contain interior mutability and a reference may not be safely transferrable across a catch_unwind boundary
  --> $DIR/not-panic-safe-2.rs:10:5
   |
LL | fn assert<T: UnwindSafe + ?Sized>() {}
   | ----------------------------------- required by `assert`
...
LL |     assert::<Rc<RefCell<i32>>>();
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::UnsafeCell<i32>` may contain interior mutability and a reference may not be safely transferrable across a catch_unwind boundary
   |
   = help: within `std::cell::RefCell<i32>`, the trait `std::panic::RefUnwindSafe` is not implemented for `std::cell::UnsafeCell<i32>`
   = note: required because it appears within the type `std::cell::RefCell<i32>`
   = note: required because of the requirements on the impl of `std::panic::UnwindSafe` for `std::rc::Rc<std::cell::RefCell<i32>>`

error[E0277]: the type `std::cell::UnsafeCell<isize>` may contain interior mutability and a reference may not be safely transferrable across a catch_unwind boundary
  --> $DIR/not-panic-safe-2.rs:10:5
   |
LL | fn assert<T: UnwindSafe + ?Sized>() {}
   | ----------------------------------- required by `assert`
...
LL |     assert::<Rc<RefCell<i32>>>();
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::UnsafeCell<isize>` may contain interior mutability and a reference may not be safely transferrable across a catch_unwind boundary
   |
   = help: within `std::cell::RefCell<i32>`, the trait `std::panic::RefUnwindSafe` is not implemented for `std::cell::UnsafeCell<isize>`
   = note: required because it appears within the type `std::cell::Cell<isize>`
   = note: required because it appears within the type `std::cell::RefCell<i32>`
   = note: required because of the requirements on the impl of `std::panic::UnwindSafe` for `std::rc::Rc<std::cell::RefCell<i32>>`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0277`.