'int' is no longer fit for purpose as described in the Standard:

    "Plain int's have the natural size suggested
     by the architecture of the execution environment"

This isn't abided anymore, as all 64-Bit platforms have 32-Bit int's.

It is for this reason that in my code I use 'uintptr_t' when I need
the 'natural size' integer.

Just this week, I found old code of mine that used 'uintptr_t', and I
went looking for where in the code I converted a pointer to an int --
but I couldn't find it. Then I realised that I was only using that
type as the 'natural' type. So maybe we should have:

    namespace std {
        typedef intptr_t int_t;
        typedef uintptr_t uint_t;
    }