c++ pointer on 64 bit machine

Question

I am using c++ under 64 bit linux, the compiler (g++) is also 64 bit. When I print the address of some variable, for example an integer, it is supposed to print a 64 bit int

Answer 1

The printing of addresses in most C++ implementations suppresses leading zeroes to make things more readable. Stuff like 0x00000000000013fd does not really add value.

When you wonder why you will normally not see anything more than 48bit values in userspace, this is because the current AMD64 architecture is just defined to have 48bit of virtual address space (as can be seen by e.g. cat /proc/cpuinfo on linux)