_ensure_critical_deps() never gets called #8846

Reporting a bug

• I have tried using the latest released version of Numba.
• I have included a self contained code sample to reproduce the problem.

My library uses Numpy and Numba. All works as expected when using a compatible Numpy version.

I rely on ImportError being raised when importing Numba while an incompatible Numpy version is installed. Then, I can disable Numba and warn the user (recommending to downgrade Numpy, for example).

I recently upgraded my library and found that ImportError is no longer raised when an incompatible Numpy version is installed. Instead, a SystemError is raised while importing _internal from numba/__init__.py, so _ensure_critical_deps() doesn't get called:

$ python
Python 3.8.10 (default, Mar 13 2023, 10:26:41) 
[GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import numba
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/jotaele/Devel/pygeomy/venv_nb/lib/python3.8/site-packages/numba/__init__.py", line 42, in <module>
    from numba.np.ufunc import (vectorize, guvectorize, threading_layer,
  File "/home/jotaele/Devel/pygeomy/venv_nb/lib/python3.8/site-packages/numba/np/ufunc/__init__.py", line 3, in <module>
    from numba.np.ufunc.decorators import Vectorize, GUVectorize, vectorize, guvectorize
  File "/home/jotaele/Devel/pygeomy/venv_nb/lib/python3.8/site-packages/numba/np/ufunc/decorators.py", line 3, in <module>
        from numba.np.ufunc import _internal
SystemError: initialization of _internal failed without raising an exception

I used the following minimal environment to reproduce the problem:

Ubuntu 20.04 LTS
Python 3.8.10

Package            Version
------------------ -------
importlib-metadata 6.1.0
llvmlite           0.39.1
numba              0.56.4
numpy              1.24.2
pip                23.0.1
setuptools         67.6.0
wheel              0.40.0
zipp               3.15.0

As a workaround I'm solving the problem by catching also SystemError while attempting to import Numba. But it doesn't provide the root cause (as _ensure_critical_deps() did) so I can't advice the user on how to solve the problem.