Question

I want to use Cython to convert multiple .pyx files into an executable package (.DLL).

How do I create a single Windows DLL from multiple .pyx via distutils?

Sample used:

sub1.pyx:

cimport sub1

class A():
    def test(self, val):
        print "A", val

sub1.pxd:

cdef class A:
    cpdef test(self,val)

sub2.pyx:

cimport sub2

class B():
    def test(self):
        return 5

sub2.pxd:

cdef class B:
    cpdef test(self)

init.py:

cimport sub1
cimport sub2

import sub1
import sub2

setup.py:

from distutils.core import setup
from distutils.extension import Extension
from Cython.Distutils import build_ext

ext_modules = [Extension("sub", ["__init__.pyx", "sub1.pyx", "sub2.pyx"])]

setup(
  name = 'Hello world app',
  cmdclass = {'build_ext': build_ext},
  ext_modules = ext_modules
)

Error:

sub1.obj : error LNK2005: ___pyx_module_is_main_sub already defined in __init__.obj
sub1.obj : error LNK2005: _initsub already defined in __init__.obj
sub2.obj : error LNK2005: ___pyx_module_is_main_sub already defined in __init__.obj
sub2.obj : error LNK2005: _initsub already defined in __init__.obj
Creating library build\temp.win32-2.7\Release\sub.lib and object build\temp.win32-2.7\Release\sub.exp
C:\temp\ctest\sub\sub.pyd : fatal error LNK1169: one or more multiply defined symbols found

Answer 1

I was not aware of this :

http://groups.google.com/group/cython-users/browse_thread/thread/cbacb7e848aeec31

I report the answer of one of the main coders (Lisandro Dalcin) of cython (sorry for cross posting):

ext_modules=[ 
    Extension("myModule", 
              sources=['src/MyFile1.pyx', 
                       'src/MyFile2.pyx'], 

You cannot have a single “myModule” built from two different sources.
Perhaps you could add a “src/myModule.pyx” file, with the two lines
below:

# file: myModule.pyx 
include "MyFile1.pyx" 
include "MyFile2.pyx" 

and then use

Extension("myModule", sources=['src/myModule.pyx'], ...)