message: Fix AliCollisionGeometry casting
diff: @@ -232,8 +232,11 @@ void AliGenCocktail::Generate()
  if(vtxGen){
  const AliHeader* hBg = vtxGen->GetHeader();
  if (hBg) {
  - AliGenHijingEventHeader* genHeader = (AliGenHijingEventHeader*)hBg->GenEventHeader();
  - coll = (AliCollisionGeometry*)genHeader;
  + AliGenEventHeader* genHeader = hBg->GenEventHeader();
  + coll = dynamic_cast<AliCollisionGeometry*>(genHeader);
  + if (!coll) {
  + AliFatalF("Header %s does not provide collision geometry",genHeader->IsA()->GetName());
  + }
  }
  }
  }
  