Another example of this misbehaviour: there are cases where ``os.stat()`` will internally fail to obtain the whole stat info (in some case related to permissions) and silently fall back to the same behaviour as Python 2.7.  In particular, it will return a result with ``st_dev == st_ino == 0``.  Of course, ``os.path.samefile()`` will then consider all such files as "the same one", which is nonsense.