UIStoryboardSegue has retain-cycle with its destinationViewController

Question

I'm driving a UIStoryboardSegue with a UIPercentDrivenInteractiveTransition that is based on a user gesture. If the gesture ends before it has reached a certain completion rate, the segue is canceled by calling cancelInteractiveTransition on the UIPercentDrivenInteractiveTransition. However, the presented view controller does not get deallocated, as it has a retain cycle with the UIStoryboardSegue, as depicted below.

I tested this with Apple's sample code on Custom View Controller Presentations and Transitions and got the same problem. The image below is actually from their own project. Simply download the project, run it, and begin a segue but cancel it before it has completed. Repeat this 50 times and the Debug Memory Graph will show 50 leaked view controllers.

Are we supposed to nullify the destination view controller manually when we want to cancel the segue, or is this a bug in iOS? (I am running iOS10 on an iPhone 7 Plus).

Here is what profiling through Instruments show:

I have downloaded the project. How do you cancel the transition? — Marcio Romero Patrnogic, Aug 07 '17 at 20:08
Choose the Swipe transition, and begin swiping left starting from the right edge. Only swipe a little bit, and then release. The segue will cancel, will controller B will be removed (but not deallocated). — Daniel Larsson, Aug 07 '17 at 20:10
Just checked the memory graph.. no leaks... Im running iOS 10.3 on iPhone 5 — Marcio Romero Patrnogic, Aug 07 '17 at 20:13
That's interesting, thanks for testing. I'm on 10.3.1, and I'm seeing leaks in both Memory Graph and Instruments. And even without looking at the leaks, you can just set a breakpoint in the second view controller's dealloc-method and see that it only gets called on the unwind segue, never when the presentation segue is canceled. ViewDidLoad is called, however, so there must a a leak. — Daniel Larsson, Aug 07 '17 at 21:14
@DanielLarsson, Have you managed to fix it? I have faced the same issue on iOS 11. — Melany, Apr 05 '18 at 12:52

UIStoryboardSegue has retain-cycle with its destinationViewController

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