There is a try/except in the f2py util testing code that masks compilation errors:

If I delete that, all the tests in test_array_from_pyobj.py fail with the following compilation error:

/Users/goldbaum/Documents/numpy/build-install/usr/lib/python3.13/site-packages/numpy/f2py/tests/src/array_from_pyobj/wrapmodule.c:118:44: error: no member named 'alignment' in 'struct _PyArray_Descr'
                       PyArray_DESCR(arr)->alignment,
                       ~~~~~~~~~~~~~~~~~~  ^

The try/except seems like a bad idea but I guess it's there for a reason for distutils support. Probably worth seeing if there are other tests like this.