src/test/ui/async-await/issue-71137.stderr

   1 error: future cannot be sent between threads safely
   2   --> $DIR/issue-71137.rs:22:3
   3    |
   4 LL |   fake_spawn(wrong_mutex());
   5    |   ^^^^^^^^^^ future returned by `wrong_mutex` is not `Send`
   6    |
   7    = help: within `impl Future`, the trait `Send` is not implemented for `MutexGuard<'_, i32>`
   8 note: future is not `Send` as this value is used across an await
   9   --> $DIR/issue-71137.rs:14:5
  10    |
  11 LL |     let mut guard = m.lock().unwrap();
  12    |         --------- has type `MutexGuard<'_, i32>` which is not `Send`
  13 LL |     (async { "right"; }).await;
  14    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ await occurs here, with `mut guard` maybe used later
  15 LL |     *guard += 1;
  16 LL |   }
  17    |   - `mut guard` is later dropped here
  18 note: required by a bound in `fake_spawn`
  19   --> $DIR/issue-71137.rs:8:27
  20    |
  21 LL | fn fake_spawn<F: Future + Send + 'static>(f: F) { }
  22    |                           ^^^^ required by this bound in `fake_spawn`
  23
  24 error: aborting due to previous error
  25