@mikeash I've confirmed that I no longer see this leak on Swift 5. It looks to be fixed by your patch! Awesome. Are there any limitations to releasing my app packaged with Swift 5 even though its Beta? (Apple rejection, etc)?
Glad to hear it! I don't think it's recommended to distribute an app built with a beta Xcode. Obviously, non-beta releases are not exactly guaranteed to be bug-free either, but it's best to wait if you can.