For C++ development for 32-bit systems (be it Linux, Mac OS or Windows, PowerPC or x86) I have initialised pointers that would otherwise be undefined (e.g. they can not immedi
It depends on the OS and the environment, of course. I don't think 0xDEADBEEF is necessarily a bad pointer in an arbitrary 32-bit system, either.
Realistically, any modern OS should be access-protecting the first few pages of process memory, so NULL should be a good invalid pointer value. Conveniently enough, it's already pre-defined for you.