PyrexOnWindows¶

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This page was migrated from the old MoinMoin-based wiki. Information may be outdated or no longer applicable. For current documentation, see python.org.

Step-by-step guide to install Pyrex on Windows and compile your first extension

A: Pyrex installation on Windows XP¶

step A.1¶

Install Python (we used version 2.4.2)

step A.2¶

Run the windows installer for Pyrex (e.g. Pyrex-0.9.3.1.win32.exe{.backtick})

step A.3¶

Install Mingw, the gcc compiler for Windows (download and run MinGW-5.1.2.exe and choose only the “base tools”: mingw-runtime 3.9{.backtick}, w32api-3.6{.backtick}, binutils 2.15.91{.backtick} and gcc-core 3.4.2{.backtick}. Add Mingw path (C:\MinGW\bin{.backtick}) to the Windows Path{.backtick} environment variable. If you already have cygwin installed, add C:\MinGW\bin{.backtick} before the Cygwin path.

step A.4¶

Edit the file c:/Python2x/Lib/distutils/distutils.cfg{.backtick} (if it does not exist, create it) and add the following lines:

[build]
compiler = mingw32

step A.5¶

MinGW links with msvcrt.dll{.backtick} whereas the main Python distribution links with msvcr71.dll{.backtick} (due to Visual C++ 2003). It is not safe to mix and blend these two different C runtime libraries. In order to make minGW link with msvcr71.dll{.backtick}, edit the text file c:\mingw\lib\gcc\mingw32\3.2.4\specs{.backtick} and change -lmsvcrt{.backtick} to -lmsvcr71{.backtick}.

B: Create your first Pyrex module¶

step B.1¶

Create a working directory (e.g. D:\pyrex_module\{.backtick}). Write a pyrex module and save it with a pyx{.backtick} extension (e.g. primes.pyx{.backtick}, code available here)

step B.2¶

Write the following python script and save it as setup.py{.backtick} in your working directory.

from distutils.core import setup
from distutils.extension import Extension
from Pyrex.Distutils import build_ext
setup(
  name = "PyrexGuide",
  ext_modules=[
    Extension("primes", ["primes.pyx"])
    ],
  cmdclass = {'build_ext': build_ext}
)

If you want to compile several modules, duplicate the line starting with Extension{.backtick} and replace primes{.backtick} by your module names.

step B.3¶

In your working directory, create a batch file called build_and_install.bat{.backtick} containing the following lines. To run the batch, double-click the file. You will see many “Warning” messages during the building process: do not worry, it is normal.

C:\Python24\python.exe setup.py build_ext install
pause

step B.4¶

Mission completed. The file primes.pyd{.backtick} (a Python Extension DLL) is now located in C:\Python24\Lib\site-packages{.backtick} and the primes{.backtick} module is available in Python. In your working directory, you can delete primes.c{.backtick} and the build{.backtick} folder created by the building process.

You can now test your new module at the python shell:

>>> import primes
>>> primes.primes(10)
[2, 3, 5, 7, 11, 13, 17, 19, 23, 29]