CODEWITHSUNDEEP
c++pythoncompilationextending
Jonathan Livni
Jonathan Livni

Reputation: 107062

Missing Python.h while trying to compile a C extension module

I'm following this tutorial on how to extend Python with C\C++ code.

The section named "Building the extension module with GCC for Microsoft Windows" fails for me with the following error:

fatal error: Python.h: No such file or directory

The section named "Building the extension module using Microsoft Visual C++" also fails with a similar error:

fatal error C1083: Cannot open include file: 'Python.h': No such file or directory

What should I do to solve this?

Upvotes: 14

Views: 51191

Answers (4)

Jaan
Jaan

Reputation: 330

For people using setuptools on Windows and want the Python.h include path to configure intellisense.

If you install Python through the Microsoft Store it installs in a privileged location. Search tools such as find and the File Explorer can't seem to find it.

Run python3 setup.py build to view the compiler output. It should find Python.h without any problems. Make sure to delete your build directory beforehand to ensure a rebuild.

You'll probably see something similar to the following (MSVC compiler output).

"C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.37.32822\bin\HostX86\x64\cl.exe" /c /nologo /O2 /W3 /GL /DNDEBUG /MD -IC:\VulkanSDK\1.3.261.1\Include "-IC:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.1776.0_x64__qbz5n2kfra8p0\include" "-IC:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.1776.0_x64__qbz5n2kfra8p0\Include" "-IC:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.37.32822\include" "-IC:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.37.32822\ATLMFC\include" "-IC:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\VS\include" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.22621.0\ucrt" "-IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22621.0\\um" "-IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22621.0\\shared" "-IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22621.0\\winrt" "-IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22621.0\\cppwinrt" "-IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\include\um" /Tcsource\native\native.c /Fobuild\temp.win-amd64-cpython-311\Release\source\native\native.obj

Look for the -IC:\some_path_to_python_include. For me it was like the following.

"C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.1776.0_x64__qbz5n2kfra8p0\include"

Add the string to your intellisense include path. You may need to convert the \ to \\ or /.

Upvotes: 0

Qin Hongbo
Qin Hongbo

Reputation: 1

The Python official documentation has already made it clear. Check it out here

The header files are typically installed with Python. On Unix, these are located in the directories prefix/include/pythonversion/ and exec_prefix/include/pythonversion/, where prefix and exec_prefix are defined by the corresponding parameters to Python’s configure script and version is '%d.%d' % sys.version_info[:2]. On Windows, the headers are installed in prefix/include, where prefix is the installation directory specified to the installer.

To include the headers, place both directories (if different) on your compiler’s search path for includes. Do not place the parent directories on the search path and then use #include ; this will break on multi-platform builds since the platform independent headers under prefix include the platform specific headers from exec_prefix.

And they have provided a convenient way to get the correct cflags that we should pass to compiler. here

So for example, here is what I got after running the command

root@36fd2072c90a:/# /usr/bin/python3-config --cflags
-I/usr/include/python3.5m -I/usr/include/python3.5m  -Wno-unused-result -Wsign-compare -g -fstack-protector-strong -Wformat -Werror=format-security  -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes

Pass those flags to the compiler, and it will work.

Upvotes: 0

Karim
Karim

Reputation: 1546

For Linux, Ubuntu users to resolve the issue of missing Python.h while compiling, simply run the following command in your terminal to install the development package of python:

In Terminal: sudo apt-get install python-dev

Good luck

Upvotes: 53

stonemetal
stonemetal

Reputation: 6208

  1. Do you have the python dev files so that you can find Python.h?
  2. Do you have the location of Python.h specified to your compiler? with gcc this is usually done through a -I path to include.

Figuring out which of those is failing will solve your problem.

from the article you linked:

gcc -c hellomodule.c -I/PythonXY/include

gcc -shared hellomodule.o -L/PythonXY/libs -lpythonXY -o hello.dll

They assumed you installed python in the default location c:\pythonXY(Where X is the major version number and Y is the minor version number).(in your case Python26) If you put python somewhere else replace /PythonXY with where ever you installed it.

Upvotes: 19

Related Questions