Can your C compiler do this:


int main()
{
  int *p;
  p  = 0;
  *p = 0;
  return 0;
}

?

>>6
Of course, same would happen in most OSes.
>>5
There's no negative addresses of course.
So if you subtracted 1 from the 0 pointer, you'd get -1, or treated as an unsigned int: 0xFFFFFFFF (on 32bit).