objc[322] Class _NSSwiftEnumeratorBase is implemented in both- 问题解决办法

objc[322]: Class _NSSwiftEnumeratorBase is implemented in both "MyAppFilePath.app"/Frameworks/libswift_stdlib_core.dylib and "MyAppFilePath.app"/Frameworks/libswiftCore.dylib. One of the two will be used. Which one is undefined.

在真机测试时出现这种问题时闪退, 是因为之前有个版本,两个版本相冲突, xcode 中按 Shift+Cmd+K  清空原来的版本就可以了, 或者手动把原来真机中的应用删掉.