Note: I reported a similar issue which has then been marked as a duplicate of this one: bpo-34223. Copy of my first message:
---
It seems like Python has an invalid object somewhere. PYTHONDUMPREFS=1 makes Python crash at exit.
$ PYTHONDUMPREFS=1 ./python -c pass
(...)
0x7f1992292448 [1] (<class '_thread._localdummy'>, <class 'object'>)
0x7f1992241aa8 [1] {'__doc__': 'Thread-local dummy'}
0x7f199222c740 [1] (<class 'object'>,)
0x9c98a0 [2] <class '_thread._localdummy'>
0x7f1992217dc0 [1]
Segmentation fault (core dumped)
---