Re: [Cython] setup.py refusing to run cython
On 14 June 2011 16:20, Nathaniel Smith <njs@pobox.com> wrote:
Hello Cython folks,
This message (see below) is the second report I've gotten of a very strange build problem with a cython module. I'm just using the standard 'from Cython.Distutils import build_ext', 'cmdclass = {"build_ext": build_ext}' incantation, but for some reason setup.py is attempting to just run gcc directly without calling cython first to generate the .c file.
You can see the setup.py here: https://code.google.com/p/scikits-sparse/source/browse/setup.py?name=scikits...
Anyone have any ideas?
Your setup.py is mixing setuptools and Cython.Distutils. Both are monkeypatching distutils, and in general that's a very bad idea. -- Lisandro Dalcin --------------- CIMEC (INTEC/CONICET-UNL) Predio CONICET-Santa Fe Colectora RN 168 Km 472, Paraje El Pozo 3000 Santa Fe, Argentina Tel: +54-342-4511594 (ext 1011) Tel/Fax: +54-342-4511169
On Tue, Jun 14, 2011 at 12:39 PM, Lisandro Dalcin <dalcinl@gmail.com> wrote:
On 14 June 2011 16:20, Nathaniel Smith <njs@pobox.com> wrote:
Hello Cython folks,
This message (see below) is the second report I've gotten of a very strange build problem with a cython module. I'm just using the standard 'from Cython.Distutils import build_ext', 'cmdclass = {"build_ext": build_ext}' incantation, but for some reason setup.py is attempting to just run gcc directly without calling cython first to generate the .c file.
You can see the setup.py here: https://code.google.com/p/scikits-sparse/source/browse/setup.py?name=scikits...
Anyone have any ideas?
Your setup.py is mixing setuptools and Cython.Distutils. Both are monkeypatching distutils, and in general that's a very bad idea.
One way to get around this is to use http://wiki.cython.org/enhancements/distutils_preprocessing - Robert
Lisandro Dalcin, 14.06.2011 21:39:
On 14 June 2011 16:20, Nathaniel Smith wrote:
Hello Cython folks,
This message (see below) is the second report I've gotten of a very strange build problem with a cython module. I'm just using the standard 'from Cython.Distutils import build_ext', 'cmdclass = {"build_ext": build_ext}' incantation, but for some reason setup.py is attempting to just run gcc directly without calling cython first to generate the .c file.
You can see the setup.py here: https://code.google.com/p/scikits-sparse/source/browse/setup.py?name=scikits...
Anyone have any ideas?
Your setup.py is mixing setuptools and Cython.Distutils. Both are monkeypatching distutils, and in general that's a very bad idea.
Specifically, "setuptools" checks the list of source files and when it sees a .pyx extension, it checks if Pyrex (!) is installed. If not, which is rather unlikely for Cython users, it changes the file extension to ".c", thus preventing Cython from compiling it. There are two ways around this. The ugly way is to put a fake Pyrex into sys.path during installation, e.g. https://github.com/lxml/lxml/tree/master/fake_pyrex A better way is to switch from "setuptools" to "distribute". Stefan
On Wed, Jun 15, 2011 at 12:18 AM, Stefan Behnel <stefan_ml@behnel.de> wrote:
Lisandro Dalcin, 14.06.2011 21:39:
On 14 June 2011 16:20, Nathaniel Smith wrote:
Hello Cython folks,
This message (see below) is the second report I've gotten of a very strange build problem with a cython module. I'm just using the standard 'from Cython.Distutils import build_ext', 'cmdclass = {"build_ext": build_ext}' incantation, but for some reason setup.py is attempting to just run gcc directly without calling cython first to generate the .c file.
You can see the setup.py here:
https://code.google.com/p/scikits-sparse/source/browse/setup.py?name=scikits...
Anyone have any ideas?
Your setup.py is mixing setuptools and Cython.Distutils. Both are monkeypatching distutils, and in general that's a very bad idea.
Specifically, "setuptools" checks the list of source files and when it sees a .pyx extension, it checks if Pyrex (!) is installed. If not, which is rather unlikely for Cython users, it changes the file extension to ".c", thus preventing Cython from compiling it.
There are two ways around this. The ugly way is to put a fake Pyrex into sys.path during installation, e.g.
Right, I'm already doing that, and it works for me...but not for all my users, I guess?
A better way is to switch from "setuptools" to "distribute".
Right, I'd just switch to plain distutils except this package uses the 'scikits' namespace package, and IIUC distutils can't handle namespace packages. I'm finding the docs for 'distribute' a bit confusing, though. Is the way that I switch from 'setuptools' to 'distribute' to just leave my code the same, and tell my users to install distribute? That seems kind of error prone... -- Nathaniel
participants (4)
-
Lisandro Dalcin -
Nathaniel Smith -
Robert Bradshaw -
Stefan Behnel