Hi @Alvaro_Lopez_Solis ,
that looks like a memory corruption issue, the most likely cause is a bug in the analysis code that e.g. writes over memory that it should not write over (beyond the last element of an array, for example), eventually causing problems in ~random places.
This is just a guess of course, based on the fact that a crash like that deep in the belly of ROOT I/O simply should not happen in normal conditions. It could also be that you are hitting a real bug we haven’t seen before, it’s just less likely.
One thing you can try is run the program (or a stripped down version of the program that still reproduces the crash) under valgrind, which will detect some classes of invalid memory accesses.
If that fails we’ll need a self-contained reproducer, as stripped down as possible, so that we can take a look on our side.
Cheers,
Enrico