I tried to re-produce the error and couldn't with main...snowman2:pyproj:docker .

To debug, I suggest modifying the CI tests to specifically run the test that fails and trying these configurations:

• set PROJ_DEBUG environment variable to 3
• add -vv flag to tests
• Install gdb and run gdb -ex=r --args /venv/bin/python -B -m pytest test/test_database.py

Also, it may not hurt to rebase this PR against the latest version.

Also, it may not hurt to rebase this PR against the latest version.

I did rebase (after some problems), but the tests are not running. Is anything broken in the gh actions?

I see this error:

The workflow is not valid. .github/workflows/tests.yaml (Line: 127, Col: 17): Unexpected value ''

I was able to re-produce this with PROJ 9.3 (both docker & conda envs) and I did not encounter any errors with PROJ 9.4 on the docker image (#1390 (comment)):

test/test_database.py 
Thread 1 "python" received signal SIGSEGV, Segmentation fault.
0x000075ff9a5b3079 in proj_list_get_count () from /lib/x86_64-linux-gnu/libproj.so.25

If logic is added in the function to not allow running in PROJ 9.3, I would be okay with adding this in.