python -m venv test
cd test
. bin/activate

pip install --verbose git+https://github.com/cython/cython
pip install cysignals
pip install setuptools # https://github.com/cython/cython/issues/5976

cat << 'EOF' > a.pyx
# cython: preliminary_late_includes_cy28=True
from cysignals.signals cimport sig_check
EOF

cythonize -X preliminary_late_includes_cy28=True -i a.pyx  # successful

rm -r a.c build/ a.cpython-311-x86_64-linux-gnu.so a.c.dep

cythonize -i a.pyx  # error

cythonize -X preliminary_late_includes_cy28=True -i a.pyx  # now error, need to clean temporary files (see below)

rm -r a.c build/ a.cpython-311-x86_64-linux-gnu.so a.c.dep

cythonize -X preliminary_late_includes_cy28=True -i a.pyx  # successful again