XCode报错 has been modified since the precompiled header was built

环境：

XCode 5.1

Mac OS 10.9

问题：“........” has been modified since the precompiled header "......." was built

解决方法：

方法1）clean项目
     * Project -> Clean
     * Shift + Command + K

方法2）删除 /Users/username/Library/Developer/Xcode/DerivedData/ModuleCache 下的所有文件

注意：如果上述解决方法没有效果，可以结合两个方法一起解决