iOS Admod loadRequest memory

xcode7.1, iOS9.1, Admob version 7.5.2 Admob loadrequest memory leak

    bannerView = GADBannerView(frame: rectBanner)
    bannerView.adUnitID = "xxxxxxxxxxxxxxxxxx"
    bannerView.rootViewController = self
    request = GADRequest()
    bannerView.loadRequest(request)
    coverBanner.addSubview(bannerView)

image: Banner Memory Leak