Accessing information from a touchable obtained from track->GetOriginTouchable() gives a segmentation fault if the track is a source (primary) particle.

Examples from steppingaction :-

G4Track* aTrack = theStep->GetTrack();
const G4VTouchable * t1= aTrack->GetOriginTouchable()  ;  // ok
G4VPhysicalVolume *p1  = t1->GetVolume()               ;  //  Instant segfault if aTrack->GetParentID()==0

But:-

if(aTrack->GetParentID()>0) G4cout<<t1->GetVolume()->GetName() << G4endl;  // ok



It's a trivial issue to work around I know. I just thought I'd report it as it caught me out for a while and may do so others also.

Please request further information if required.


Thanks 

Steve Quillin