从XCODE 5的目录中:

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs

把iPhoneOS7.1.sdk 这个文件夹拷贝到 XCODE 6的

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs

中即可.