I never understood this one. I mean obviously a kind compiler should warn you against using

    while true { }

and

    while i < 5 { i—-; }

but in general, I don’t find distinction between “this infinite loop terminates” (e.g. an event loop) and “this code obviously terminates but not in the lifetime of this universe” (e.g. computing Ackermann(5)) to be that useful.