warning:Could not resolve external type c:@S@CGSize

编译时 报错  warning:Could not resolve external type c:@S@CGSize  解决方法

配置Bulid Setting 中Debug Information Format中的Debug 为DWARF

关于DWARF和dSYM的解释等参考资料：

http://www.cnblogs.com/whyandinside/archive/2013/04/28/3048366.html

http://stackoverflow.com/questions/33029490/xcode-7-warnings-with-google-signin-lib-when-building-project