错误：bject contains invalid bitcode

在xcode7.1进行Archive时，会报这样的错误

ld: object contains invalid bitcode: /Users/XXX/UMSocial_Sdk_Extra_Frameworks/Wechat/libWeChatSDK.a(WechatAuthSDK.o) for architecture arm64

clang: error: linker command failed with exit code 1 (use -v to see invocation)

http://blog.youkuaiyun.com/watson2017/article/details/51568723

解决方法：Build Settings中，把Enable Bitcode设置为NO