Problems reading with ROOT5 files created with ROOT6

Hi all,

we have some recent MC productions created with ROOT 6.30/04. While we migrated our analysis software to ROOT6, still some people use the version based on ROOT 5.34.36. They tried to read the file attached, and they get crashes. For example:

root [0] TFile *f = TFile::Open("GA_M1_za05to35_8_855617_Y_w0.root")
Warning in <TClass::TClass>: no dictionary for class TVirtualPaveStats is available
Warning in <TClass::TClass>: no dictionary for class ROOT::TIOFeatures is available
root [1] f->ls()
TFile**		GA_M1_za05to35_8_855617_Y_w0.root	Untitled
 TFile*		GA_M1_za05to35_8_855617_Y_w0.root	Untitled
  KEY: TTree	OriginalMC;1	Tree containing MMcEvtBasic
  KEY: TTree	RunTails;1	Tree containing MMarsVersion_sorcerer [MMarsVersion]
  KEY: TTree	RunHeaders;1	Tree containing MRawRunHeader
  KEY: TTree	Events;1	Tree containing MMcEvt
  KEY: MHCamera	Unsuitable;avg;cpy;1	Fraction of unsuitable events per Pixel
  KEY: MHCamera	Unsuitable;avg;1	Fraction of unsuitable events per Pixel
  KEY: MHCamera	ShowerCharge;cpy;1	Mean Calibrated Signal
  KEY: MHCamera	ShowerRMSCharge;cpy;1	RMS of Calibrated Signal
  KEY: MHCamera	ShowerHitFraction;cpy;1	Hit Fraction
  KEY: MHCamera	ShowerMeanArrTime;cpy;1	Mean raw arrival time
  KEY: MHCamera	ShowerRMSArrTime;cpy;1	RMS raw arrival time
  KEY: MHCamera	ShowerMeanCalTime;cpy;1	Mean calibrated arrival time
  KEY: MHCamera	ShowerRMSCalTime;cpy;1	RMS calibrated arrival time
root [2] .q

 *** Break *** segmentation violation

this is even without reading anything from the trees, also that fails. I thought that to some degree it would have been possible to read files containing TTrees created with ROOT6 with ROOT5, but it seems it is not the case. Looking around the forum, I saw posts where similar warnings like the ones after creating the TFile object were reported, but the ROOT versions affected is not the one used here.

Any ideas on what could be the issue?

Cheers,
Alessio

GA_M1_za05to35_8_855617_Y_w0.zip (1.6 MB)

Hello,
let me ping @pcanal and @Danilo, they should be able to help you.

Maybe related: Compatiblity issue: File writting with root 6.32/02 cannot be read back with root 6.10/06 · Issue #15964 · root-project/root · GitHub

Please run:

valgrind --num-callers=50- --log-file=val.5.34.log --suppressions=$ROOTSYS/etc/valgrind-root.supp root.exe -b -l -q GA_M1_za05to35_8_855617_Y_w0.root

in the failing case and send up val.5.34.log.

Sorry for the delay @pcanal, here you can find the log file attached after running valgrind.

Cheers,
Alessio

val.5.34.txt (84.8 KB)