SceneKit App fails with EXC_BAD_ACCESS on iOS9 - objective-c

Question

We've bumped into a problem with one of our apps that uses SceneKit when deployed on iOS9. The app works great on iOS8.0-8.4, but when deployed on iOS9, it immediately crashes. Looking at the crash logs, we are seeing an EXC_BAD_ACCESS exception in a thread. The specific error states com.apple.scenekit.renderingQueue.SCNView Thread 11 crashed. Thinking that it was somehow related to the complexity of the scene, we dropped the scene back to nothing but a 3d box, and the app still crashes. The code that renders the box is as follows. It seems awfully simple to be crashing. And it's very weird that this runs fine on everything prior to iOS9 and runs fine on the simulator for iOS9. It only crashes when deployed. (This is an Enterprise app).
The crash occurs on the line of code that reads:
[scene.rootNode addChildNode:boxNode];
What am I missing?? Thanks for any help.
#implementation TreasureChestViewController
#synthesize sceneView;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Create the SCNView
}
-(void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
// Add scene an empty scene
scene = [SCNScene scene];
// Set the scene to the view
sceneView.scene = scene;
// Create and add a camera to the scene
SCNNode *cameraNode = [SCNNode node];
cameraNode.camera = [SCNCamera camera];
cameraNode.position = SCNVector3Make(0,15, 30);
[scene.rootNode addChildNode:cameraNode];
// Create and add a light to the scene
SCNLight *spotLight = [SCNLight light];
spotLight.type = SCNLightTypeSpot;
spotLight.color = [UIColor whiteColor];
SCNNode *spotLightNode = [SCNNode node];
spotLightNode.light = spotLight;
spotLightNode.position = SCNVector3Make(0, cameraNode.position.y, 20);
[cameraNode addChildNode:spotLightNode];
// A square box
CGFloat boxSide = 15.0;
SCNBox *box = [SCNBox boxWithWidth:boxSide
height:boxSide
length:boxSide
chamferRadius:0];
SCNNode *boxNode = [SCNNode nodeWithGeometry:box];
// boxNode.transform = CATransform3DMakeRotation(M_PI_2/3, 0, 1, 0);
[scene.rootNode addChildNode:boxNode];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
#end