Interesting but not understandable.

For someone like me teetering the edge of beginner, could you point to a good starting resource for what is being discussed here? Bitwise operators are way above me

Thanks for the link, @hobovsky!

I'll give it a read :)

Except this is UB: https://stackoverflow.com/a/28783339/1756361

This is the approach I took too, except I moved mine into a macro to keep it a little more readable and re-usable:

#define SWAP(x, y) (x ^= y ^= x ^= y)

I had to work this out in a Base Mode calculator to figure it out. Placeholders be damned; this is how I'm swapping values for now on

I needed your explanation (and paper/pen) to understand it. Thank you.

I only try to explain the swap mechanism because it took time for me to understand, so I made the post because newbies could understand. Sorry I am a teacher.
But you are right, no checking of the parameters is always a bad thing.

Clever it might be. But you better be sure that p1 and p2 can never point to the same memory location before even thinking about this.