> But from my own experience, UB just means "consult your compiler to see what it does here because this question is beyond our pay grade."
Careful. It's not just "consult your compiler", because the behavior of a given compiler on code containing UB is also allowed to vary based on specific compiler version, and OS, and hardware, and the phase of the moon.
Careful. It's not just "consult your compiler", because the behavior of a given compiler on code containing UB is also allowed to vary based on specific compiler version, and OS, and hardware, and the phase of the moon.