CATileLayer seems deallocating SubView's layer unexpected

I found that ,If a Parent View was CATiledLayer based, it will deallocating its SubView's layer before the SubView object is deallocating it self (When SubView object is retained in some async opertaions, and Parent View is deallocating). This can cause some zombie memory issues. If the Parent View is CALayer based , everything is OK.

I have done a zombie profiling for both layers situations.

Seems the only diffrence between them is _UIViewWillBeRemovedFromSuperview will be called only for CALayer based ParentView ,
and without
_UIViewWillBeRemovedFromSuperview called , the SubView's layer object 's reference count seem wrong and the zombie object comes out

demo code can be found here:

demo code

It seems that addSubView is not permit for CATiledLayer based View?
CATileLayer seems deallocating SubView's layer unexpected
 
 
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