int64_t is a much nicer type than "long long".

"int" makes some sense. Word-size of the machine.

"short", "long", "long long" are all non-sensical. You use them when you want to trade size and range. When you want to make that trade-off, you care what their sizes are.

Instead of lower/upper bounds on their sizes, which aren't very useful, they should just have specific sizes. At which point, you might as well use uint32_t, and uint64_t in place of long and long long.

Prefer the sized int types over the "long"/"long long" ones when you can, for saner coding.

Use uintptr_t and such when you need a ptr-sized int, rather than a specific size.