[Dylan16807]

Loops that do nothing and don't terminate.

If your loop infinitely writes the number 70 to an atomic int, it's fine.

[volta87]

If by "nothing" you mean "nothing but looping", then yes, you are right. Any loop that "just loops" is doing something by definition: looping.

[Dylan16807]

It depends on your perspective. Normally when I talk about what a loop "does", I am talking purely about the contents of the loop.