PYTHON setup.py build_ext --inplace
PYTHON -c "import a"
PYTHON -c "import b"

######## setup.py ########

from Cython.Build import cythonize
from distutils.core import setup

setup(
    ext_modules = cythonize("*.pyx"),
)

######## a.pxd ########
# cython: preliminary_late_includes_cy28=True

cdef extern from "a_early.h":
  ctypedef int my_int

cdef extern from "a_late.h":
    my_int square_value_plus_one()

cdef my_int my_value "my_value"

cdef my_int square "square"(my_int x)

######## a.pyx ########

my_value = 10

cdef my_int square "square"(my_int x):
    return x * x

assert square_value_plus_one() == 101

# Square must be explicitly used for its proto to be generated.
cdef my_int use_square(x):
  return square(x)

######## a_early.h ########

typedef int my_int;

######## a_late.h ########

static my_int square_value_plus_one() {
  return square(my_value) + 1;
}

######## b.pyx ########

cimport a

# Likewise, a.square must be explicitly used.
assert a.square(a.my_value) + 1 == 101
assert a.square_value_plus_one() == 101