Question

Given the following code:

value = time.mktime(datetime.fromtimestamp(timestamp).timetuple())

Is it possible for this to produce an OverflowError ‘mktime argument out of range’ and, if so, what range of timestamps would cause this?

Answer 1

Yes. I’m two hours ahead of UTC and on Windows. I get the error in the last two hours of the int32 range:

>>> def roundtrip(x):
...     return time.mktime(datetime.datetime.fromtimestamp(x).timetuple())
...
>>> roundtrip(2**31-1-7200)
2147476447.0
>>> roundtrip(2**31-7200)
OverflowError: mktime argument out of range
>>> roundtrip(2**31-1)
OverflowError: mktime argument out of range
>>> roundtrip(2**31)
ValueError: timestamp out of range for platform time_t