For Python 3.0.1 few changes in "API" were implemented that cause troubles with pyCXX 6.0.0.
Here are these two issues:
- Issue #1717: Removed builtin cmp() function, dropped tp_compare
slot, the C API functions PyObject_Compare and PyUnicode_Compare and
the type definition cmpfunc. The tp_compare slot has been renamed
to tp_reserved, and is reserved for future usage.
- Issue #4910: Rename nb_long slot to nb_reserved, and change its
type to (void *).