4 ms·

But you _don't_ know what it returns, because the behavior is either undefined or implementation defined, and you don't know the implementation.

• ben509 7y ago
  But you do know that it's undefined or implementation defined. It's a "known unknown".
  • H8crilA 7y ago
    Look, do you know what will it return or not?
    • saagarjha 7y ago
      Not without knowing the compiler, which I think was the point.
  • Thorrez 7y ago
    Yes, so you knowingly click "I don't know". You don't know the value, and you know that you don't know the value.