Error in <TTreeReaderArrayBase::GetBranchContentDataType()>: The branch h.fData.fPx contains a data type 9 for which the dictionary cannot be retrieved.

#include "TTree.h"
#include "TTreeReader.h"
#include "TTreeReaderArray.h"

struct Inside {
  Double32_t fPx;
  double fPy;
};

struct Holder {
  std::vector<Double32_t> fValues;
  std::vector<Inside> fData;
};

#ifdef __ROOTCLING__
#pragma link C++ class Inside+;
#pragma link C++ class Holder+;
#pragma link C++ class std::vector<Inside>+;
#pragma link C++ class std::vector<Double32_t>+;
#endif

void exec()
{
  auto t = new TTree("t","t");
  Holder h;
  t->Branch("h.", &h);
  t->Fill();
  t->Print();
  TTreeReader r(t);
  //TTreeReaderArray<Double32_t> arr1(r, "h.fValues");
  TTreeReaderArray<Double32_t> arr2(r, "h.fData.fPx");
  TTreeReaderArray<Double32_t> arr3(r, "h.fData.fPy");
  r.Next();
 // arr1.GetSize();
  arr2.GetSize();
  arr3.GetSize();
}