message: Incorrect usage has been modified
diff: #pragma link C++ class AliFemtoEventReaderNanoAOD+;
  #pragma link C++ class AliFemtoEventReaderNanoAODChain+;
  #pragma link C++ class AliFemtoEventReaderAODKinematicsMultSelection+;
  +// Dong-Fang: 2021.9.14
  +#pragma link C++ class AliFemtoSimpleAnalysisOnlyMixP1+;
  +#pragma link C++ class AliFemtoVertexMultAnalysisOnlyMixP1+;
  #pragma link C++ class AliFemtoConfigObject-;
  #pragma link C++ class AliFemtoConfigObject::Painter;
  #pragma link C++ class std::vector<AliFemtoConfigObject>::iterator;
  #pragma link C++ class std::vector<std::pair<double, double>>;
  -// Dong-Fang: 2021.9.14
  -#pragma link C++ class AliFemtoSimpleAnalysisOnlyMixP1;
  -#pragma link C++ class AliFemtoVertexMultAnalysisOnlyMixP1;
  +
  // ^ these std:: classes required here for use in ROOT-5 macros (ROOT-6 should be ok)
  #endif
  