Open Radar

 
Area:
MapKit

Summary:
Deallocation of an `MKMapView` after the addition of annotations will cause a crash.

Steps to Reproduce:
Create blank `UIViewController` embedded within a `UINavigationController` with button which triggers segue to push another view controller.
In the second `UIViewController` place a `MKMapView` and in `viewDidLoad` add an array of annotations:
`addAnnotations(newAnnotations)`
animate the display of the annotations:
`showAnnotations(newAnnotations, animated: true)`
While the animation is taking place quickly press the back button to deallocate the view controller and it's child map view.

Expected Results:
The view controller should be popped without issue.

Actual Results:
The app will crash because the map view will attempt to add the annotations after deallocation.

Version/Build:
Xcode Version 9.1 (9B55)
iOS 11.1.2 (15B202)

Configuration: