我在 Reachability 类中使用 SystemConfiguration ，但不知道崩溃来自哪里
> libobjc.A.dylib objc_msgSend + 16 1 SystemConfiguration
> reachPerformAndUnlock + 640 2 CoreFoundation
> __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 24 3 CoreFoundation
> __CFRunLoopDoSources0 + 524 4 CoreFoundation
> __CFRunLoopRun + 804 5 CoreFoundation CFRunLoopRunSpecific + 444 6 GraphicsServices GSEventRunModal + 180 7 UIKit
> -[UIApplication _run] + 684 8 UIKit UIApplicationMain + 208 9 MoveInSync AppDelegate.swift line 38 main