我编写了一个使用Google Identity Toolkit登录的应用程序，在我更新到最新版本的Xcode并开始为iOS 9开发之前它一直运行良好。我不得不使用Cocoapods安装GITkit，这似乎是成功的，但现在编译时，当我引用某些内置类时，我得到以下错误。另外，我必须将导入语句从#import <GITkit/GITkit.h>更改为#import "GITkit.h"。
Undefined symbols for architecture x86_64:
"_OBJC_CLASS_$_GITClient", referenced from:
objc-class-ref in H2LoginViewController.o
objc-class-ref in H2AppDelegate.o
"_OBJC_CLASS_$_GITIDToken", referenced from:
objc-class-ref in H2LoginViewController.o
"_OBJC_CLASS_$_GITInterfaceManager", referenced from:
objc-class-ref in H2LoginViewController.o
"_kGITProviderFacebook", referenced from:
-[H2AppDelegate application:didFinishLaunchingWithOptions:] in H2AppDelegate.o
"_kGITProviderGoogle", referenced from:
-[H2AppDelegate application:didFinishLaunchingWithOptions:] in H2AppDelegate.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
非常感谢任何帮助。感谢。