How to solve this "Segmentation Fault"?

I use LLDB to debug my program. The print info is as follows.


What should I do to make the program work correctly.

You probably passed in a null pointer for G4Material* somewhere up your calling chain. Since this is generating the production cuts table (look at your traceback and read the names of the classes and functions), perhaps you set a null material pointer somewhere in your geometry setup.

Thank you. I find the problem with geometry. It seems that GDML can not couple with Geant4 native geometry definition.