Uploaded image for project: 'ROOT'
  1. ROOT
  2. ROOT-10023

[TTreeReader] Unable to read TBranchObject

    XMLWordPrintable

    Details

    • Type: Bug
    • Status: Closed (View Workflow)
    • Priority: High
    • Resolution: Fixed
    • Affects Version/s: 6.18/00
    • Fix Version/s: 6.24/00, 6.22/02
    • Component/s: None
    • Labels:
      None
    • Environment:

      any

      Description

      Problems with RDataFrame and TBranchObjects first reported on the forum here.

      Using the file provided by the forum user, at https://cernbox.cern.ch/index.php/s/CcgXcCJMweaaTck , a simple reproducer for the issue is:

      #include <TFile.h>
      #include <TTreeReader.h>
      #include <TTreeReaderValue.h>
      #include <TH2F.h>
       
      int main()
      {
              TFile *_file0 = TFile::Open("dqmio.root");
              TTree *MEs = nullptr;
              _file0->GetObject("MEs", MEs);
              TTreeReader r(MEs);
              TTreeReaderValue<TH2F> histo(r, "value");
              r.Next();
              *histo;
              return 0;
      }
      

      which prints Error in <TBranchProxy::Read>: Unable to initialize value.

      The problem seems to be that TBranchProxy::Setup does not have any logic to deal with TBranchObject s, cannot retrieve the value address (fWhere ) and therefore returns false at TBranchProxy.cxx:487 .

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                eguiraud Enrico Guiraud
                Reporter:
                eguiraud Enrico Guiraud
              • Votes:
                0 Vote for this issue
                Watchers:
                1 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: