Error in <TList: Clear> while running ExternalFastJet examples

[huiluo]

Dear Authors,

I installed Delphes-3.4.1 in a linux mint os, when I set all the paths and library paths done, and tried to compile and run ExternalFastJetBasic.cpp and ExternalFastJetHepMC.cpp in the /examples/ExternalFastJet/, there is a common error appearing as "Error in <TList::Clear>: A list is accessing an object (0x3da6170) already deleted (list name = TList)".

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The following is the error appearing during running two examples :

Running ExternalFastJetBasic.cpp

Ran Longitudinally invariant anti-kt algorithm with R = 0.5 and E scheme recombination
jet # rapidity phi pt

0 -2.01601011 2.54178888 0.36166400

Ran Longitudinally invariant anti-kt algorithm with R = 0.5 and E scheme recombination
jet # rapidity phi pt

0 4.32921403 5.80116310 0.48191013

Error in <TList::Clear>: A list is accessing an object (0x3da6170) already deleted (list name = TList)

Running ExternalFastJetHepMC.cpp

Reading test.hepmc
Ran Longitudinally invariant anti-kt algorithm with R = 0.5 and E scheme recombination
jet # rapidity phi pt

0 -1.76735699 3.13177896 1.46900207
1 4.20523962 5.92114144 1.20532529
2 -3.64015265 2.43190443 1.18645317
3 -0.55877473 4.24618479 1.08160774
4 1.71355328 2.91132347 0.90986696
5 -4.93952294 0.19578137 0.42742498
6 -4.93289432 4.77336044 0.34282133

Exiting...
Error in <TList::Clear>: A list is accessing an object (0x39b91b0) already deleted (list name = TList)

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However, after I comment out the line: "delete modularDelphes;" in both .cpp files, this error goes away. Actually, I don't quite understand why this happened? Does the "delete modularDelphes;" duplicates the utility "modularDelphes->FinishTask();" beforehand?

Thank you in advance.

Hui

[Pavel Demin]

This error is already fixed in our git repository. Here is a link to the fix:
​​https://github.com/delphes/delphes/commit/2fedc726ee59739a21376817ca09ac05849e2f12

Since the error appears after the output file is already written to the disk, it's safe to use Delphes without applying this fix.