Enums declared in class scope are ignored by genreflex

[Nowakus]

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Description

Genreflex seems to notice only the enums that were defined directly in a namespace scope. If an enum is defined inside a class scope, genreflex will (silently!) ignore the selection directive. The fact that it works in a specific case would suggest that the machinery is there, it just does not get triggered in all cases that it should

Reproducer

enum.genreflex.tgz

Running genreflex on the attached source will produce a rootmap file that has entries for only 2 enums (out of 12 defined and 6 selected):

[ libclasses.so ]
# List of selected classes
class MyClass
class OtherClass
# List of selected enums and outer classes
enum myNamespace::EnumSEL
enum myNamespace::EnumClassSEL

ROOT version

6.36, master

Installation method

SFT builds used by ATLAS

Operating system

lxplus

Additional context

No response

[hahnjo]

Hi @Nowakus, I confirm the enums nested in classes are not there. However, compiling the dictionary to the appropriate shared library:

g++ -fPIC `root-config --cflags` classes_rflx.cpp `root-config --libs` --shared -o libclasses.so

and then using the test program written for #13303

#include <TEnum.h>
#include <TInterpreter.h>

#include <iostream>

int main() {
  TInterpreter::SuspendAutoParsing suspendAutoParsing(gInterpreter);
  // No idea how this is different from the above, but it calls a different method...
  gInterpreter->SetClassAutoparsing(false);

  auto E = TEnum::GetEnum("OtherClass::EnumSEL");
  std::cout << "OtherClass::EnumSEL = " << E << "\n";

  return 0;
}

confirms that having a rootmap entry for the outer class is sufficient to trigger auto-loading and then find the enum:

 $ g++ -o enum enum.cxx $(root-config --cflags --libs)
 $ ./enum 
Warning in <TInterpreter::LoadLibraryMap>: please rename ./rootmap.rootmap to end with ".rootmap"
OtherClass::EnumSEL = 0x55ce7b7d6a40

We would need to understand why this is not working for your original case...

[Nowakus]

The TEnum::GetEnum() could be doing something different than the RNTupleReader. For example these 2 usecases (from my original setup) seem to report different autoparsing:

root [0] TEnum::GetEnum("CaloSampling::CaloSample")
(TEnum *) 0x1b1d060
root [1] gInterpreter->Print("autoparsed")
Auto parsed classes:
root [2] ...

root [0] ROOT::RNTupleReader::Open("EventData","myAOD.pool.root")->PrintInfo()
root [1] gInterpreter->Print("autoparsed")
Auto parsed classes:
  CaloSampling

[hahnjo]

The TEnum::GetEnum() could be doing something different than the RNTupleReader.

Yes, RNTupleReader::Open and RFieldBase::Create do more than TEnum::GetEnum. @jblomer also recently changed the interaction(s) in #21754...

root [0] ROOT::RNTupleReader::Open("EventData","myAOD.pool.root")->PrintInfo()
root [1] gInterpreter->Print("autoparsed")
Auto parsed classes:
CaloSampling

Now this is curious: It's autoparsing the containing CaloSampling class, not for the CaloSample enum...

[Nowakus]

CaloSampling is the class that holds the enum definition. I am assuming it is caused by the enum - but I could be wrong...

Edit: So Indeed, when I add this by hand to the rootmap file:

   # List of selected classes
   enum CaloSampling::CaloSample

There is no autoparsing reported anymore.