libc++abi.dylib: terminating with uncaught exception of type NSException

用wkwebview加载网络地址,一直提示这个问题

断点奔溃到Uiviewcontroller loadviewifrequired

但是也找不到原因,在plist文件加了所有的域名或者ip地址还是,最后把所有的代理方法全部打log.找到问题

 @available(iOS 8.0, *)
    func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Swift.Void)
    {
         XLLog(message: "")
        let cred = URLCredential.init(trust: challenge.protectionSpace.serverTrust!)
        completionHandler(.useCredential, cred)
        
    }