In async expressions, remove any regions that are thread-local or whom contain thread() fields.
Also remove any regions that share non-safe fields with those regions (i.e. those that couldn't be run in conjunction with that region). This prevents thread-local state leaking out.
In async expressions, remove any regions that are thread-local or whom contain thread() fields.
Also remove any regions that share non-safe fields with those regions (i.e. those that couldn't be run in conjunction with that region). This prevents thread-local state leaking out.