Github user omalley commented on the issue:
https://github.com/apache/orc/pull/197
Your HAS_POST_2038 doesn't do the correct test.
The point of the HAS_POST_2038 isn't that gmtime fails, it is that the
timezone information continues in 2038. MacOS is the last hold out using the
old 32 bit timezone files.
So the current test uses Americas/Los_Angeles and checks to see if daylight
savings happens in 2038. Your test for HAS_POST_2038 erroneously passes on
MacOS. ---
