这个是Xcode缓存导致的
fatal error: file '
'/
/Users/smile/Library/Developer/Xcode/DerivedData/ModuleCache/VE5HTVL861UA' was built
note: after modifying system headers, please delete the module cache at '/Users/ligang/Library/Developer/Xcode/DerivedData/ModuleCache/1O5WP9283VGUA'
1 error generated.
解决方法:点击Xcode-》window->organizer 删除缓存