error[E0277]: `*mut _` cannot be shared between threads safely
   --> tests/ui/compile-fail-3.rs:7:5
    |
7   |     thread::spawn(|| {
    |     ^^^^^^^^^^^^^ `*mut _` cannot be shared between threads safely
    |
    = help: the trait `Sync` is not implemented for `*mut _`
    = note: required because of the requirements on the impl of `Send` for `&*mut _`
    = note: required because it appears within the type `[closure@$DIR/tests/ui/compile-fail-3.rs:7:19: 9:6]`