Abhinav Srivastava wrote: > 1) what are the ways in which an indirect call instruction can be overwritten by a direct call instruction inside the memory? I don't understand this question. > 2) Is it possible to modify gcc in such a way that it generates some "NOP" instructions after each indirect function calls? Yes, that can be done. I don't really know enough about your skills to say how long it would take you. Andrew.