tests/ui/sync/suggest-ref-cell.stderr

   1 error[E0277]: `RefCell<()>` cannot be shared between threads safely
   2   --> $DIR/suggest-ref-cell.rs:6:20
   3    |
   4 LL |     require_sync::<std::cell::RefCell<()>>();
   5    |                    ^^^^^^^^^^^^^^^^^^^^^^ `RefCell<()>` cannot be shared between threads safely
   6    |
   7    = help: the trait `Sync` is not implemented for `RefCell<()>`
   8    = note: if you want to do aliasing and mutation between multiple threads, use `std::sync::RwLock` instead
   9 note: required by a bound in `require_sync`
  10   --> $DIR/suggest-ref-cell.rs:1:20
  11    |
  12 LL | fn require_sync<T: Sync>() {}
  13    |                    ^^^^ required by this bound in `require_sync`
  14
  15 error: aborting due to previous error
  16
  17 For more information about this error, try `rustc --explain E0277`.