Point taken. I agree that the weakly typed nature of C (integer promotions / implicit casts) can be problematic. Would be interesting to see if there are programs that would be painful to write with a stricter model.
It seems I've never really done "overshifting", otherwise I would have easily noticed that the shifted value is promoted first. If you don't overshift there's no way to trigger the undefined behaviour, even when you shift multiple times - since by assigning to the smaller type the result gets cut down again, effectively leading to the behaviour I'd assumed. I would hardly call this a gotcha.
Where it might be confusing is in a situation like this:
char x = 42;
printf("%d\n", x << 4);
But then again I'm undecided if the behaviour is that bad. It might be even useful.
It seems I've never really done "overshifting", otherwise I would have easily noticed that the shifted value is promoted first. If you don't overshift there's no way to trigger the undefined behaviour, even when you shift multiple times - since by assigning to the smaller type the result gets cut down again, effectively leading to the behaviour I'd assumed. I would hardly call this a gotcha.
Where it might be confusing is in a situation like this:
But then again I'm undecided if the behaviour is that bad. It might be even useful.