• WindowsCompilers

Even though Python is an interpreted language, you may need to install Windows C++ compilers in some cases. Unlike Linux, compilers for Windows are not included by default in the OS.

For example, you will need to use them if you wish to:

• Install a non-pure Python package from sources with Pip (if there is no Wheel package provided).

• Compile a Cython or Pyrex file.

Microsoft provides official C++ compilers called Visual C++, you can find them bundled with Visual Studio or, for some versions, in standalone distributions. Some alternative compilers exist like MinGW, but incompatibilities may occur with a CPython official distribution that is built with Microsoft Visual C++.

The compiler's architecture must be the same as Python's (for example: if you use Python 64bit, you have to use an x64 compiler).

Which Microsoft Visual C++ compiler to use with a specific Python version ?

Each Python version uses a specific compiler version (e.g. CPython 2.7 uses Visual C++ 9.0, CPython 3.3 uses Visual C++ 10.0, etc). So, you need to install the compiler version that corresponds to your Python version :

Compilers Installation and configuration

Compatible architectures are specified for each compiler in brackets.

Microsoft Visual C++ 14.0 standalone: Visual C++ Build Tools 2015 (x86, x64, ARM)

This is a standalone version of Visual C++ 14.0 compiler, you don't need to install Visual Studio 2015.

• Install Microsoft Visual C++ Build Tools 2015. Check Windows 8.1 SDK and Windows 10 SDK options.

You have to run your commands from Visual C++ Build Tools Command Prompt (C:\Program Files (x86)\Microsoft Visual C++ Build Tools\) each time you want compile with Python.

If you want automatic use of this compiler with Python, you can also edit the C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat and replace its contents with the following text :

   1 rem Vcvarsall for Visual C++ Build Tools 2015
   2 @echo off
   3 set vcprogramfiles=%ProgramFiles(x86)%
   4 if "%vcprogramfiles%"=="" set vcprogramfiles=%ProgramFiles%
   5 call "%vcprogramfiles%\Microsoft Visual C++ Build Tools\vcbuildtools.bat" %*

Microsoft Visual C++ 14.0 with Visual Studio 2015 (x86, x64, ARM)

Visual Studio 2015 contains Visual C++ 14.0 compiler. Distutils will automatically detect the compiler and use it.

Microsoft Visual C++ 10.0 standalone: Windows SDK 7.1 (x86, x64, ia64)

This is a standalone version of Visual C++ 10.0 compiler, you don't need to install Visual Studio 2010.

• Uninstall Microsoft Visual C++ 2010 Redistributable if present (all versions and architectures). If present, it can cause an error on Windows SDK 7.1 installation.

• Install Microsoft .NET Framework 4 if not present.

• Install Microsoft Windows SDK for Windows 7 and .NET Framework 4. Check Windows headers and libraries, Visual C++ Compilers and Windows Native Code Development\Tools options only.

• Install Microsoft Visual C++ 2010 Service Pack 1 Compiler Update for the Windows SDK 7.1. This updates the compiler to Visual C++ 10.0 SP1.

• reinstall Microsoft Visual C++ 2010 Redistributable (for all previously installed architectures).

You have to run your commands from Windows SDK 7.1 Command Prompt (C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1\Bin\SetEnv.cmd) each time you want to compile with Python. By default, SetEnv.cmd uses the x86 architecture, use /x64 or /ia64 arguments to change it.

If you want automatic use of this compiler with Python, you can also edit the C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\vcvarsall.bat file and replace its contents with the following text :

   1 rem Vcvarsall for Windows SDK 7.1
   2 @echo off
   3 if /i "%1" == "x64" (
   4     set vcvararch=x64
   5 ) else if /i "%1" == "amd64" (
   6     set vcvararch=x64
   7 ) else if /i "%1" == "x86_amd64" (
   8     set vcvararch=x64
   9 ) else if /i "%1" == "ia64" (
  10     set vcvararch=ia64
  11 ) else if /i "%1" == "x86_ia64" (
  12     set vcvararch=ia64
  13 ) else (
  14     set vcvararch=x86
  15 )
  16 set vcprogramfiles=%ProgramFiles(x86)%
  17 if "%vcprogramfiles%"=="" set vcprogramfiles=%ProgramFiles%
  18 call "%vcprogramfiles%\Microsoft SDKs\Windows\v7.1\Bin\SetEnv.cmd" /%vcvararch%

Microsoft Visual C++ 10.0 with Visual Studio 2010 (x86, x64, ia64)

Visual Studio 2010 contains Visual C++ 10.0 compiler. Distutils will automatically detect the compiler and use it. The Express edition of Visual Studio 2010 only bundles a compiler for x86.

Microsoft Visual C++ 9.0 standalone: Visual C++ Compiler for Python 2.7 (x86, x64)

This is a standalone version of Visual C++ 9.0 compiler, you don't need to install Visual Studio 2008.

• Install Microsoft Visual C++ Compiler for Python 2.7.

• Make sure setuptools version is at least 6.0 or it will not correctly detect the compiler path. Simply run the following in command prompt to update it:

pip install --upgrade setuptools

Even though this package's name refers to Python 2.7 specifically, you can use it with all Python versions that use Visual C++ 9.0.

Microsoft Visual C++ 9.0 standalone: Windows SDK 7.0 (x86, x64, ia64)

This is a standalone version of Visual C++ 9.0 compiler, you don't need to install Visual Studio 2008.

The use of Microsoft Visual C++ Compiler for Python 2.7 is recommended (If you don't need to compile for ia64). See the previous paragraph to install it.

• Install Microsoft .NET Framework 3.5 SP1 if not present.

• Install Microsoft Windows SDK for Windows 7 and .NET Framework 3.5 SP1. Check Windows headers and libraries, Visual C++ Compilers and Win32 Developement Tools options only.

• Set the DISTUTILS_USE_SDK environment variable to 1.

You have to run your commands from Windows SDK 7.0 Command Prompt (C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0\Bin\SetEnv.cmd) each time you want to compile with Python. By default, SetEnv.cmd uses the x86 architecture, use /x64 or /ia64 arguments to change it.

Microsoft Visual C++ 9.0 standalone: Windows SDK 6.1 (x86, x64, ia64)

This is a standalone version of Visual C++ 9.0 compiler, you don't need to install Visual Studio 2008.

Windows SDK 6.1 was upgraded by Microsoft to Windows SDK 7.0. See the previous paragraph to install it.

• Install Microsoft .NET Framework 3.5 SP1 if not present.

• Install Windows SDK for Windows Server 2008 and .NET Framework 3.5. Check Windows headers and libraries, Visual C++ Compilers and Win32 Development Tools options only.

• Set the DISTUTILS_USE_SDK environment variable to 1.

You have to run your commands from Windows SDK 6.1 Command Prompt (C:\Program Files (x86)\Microsoft SDKs\Windows\v6.1\Bin\SetEnv.cmd) each time you want to compile with Python. By default, SetEnv.cmd uses the x86 architecture, use /x64 or /ia64 arguments to change it.

Microsoft Visual C++ 9.0 with Visual Studio 2008 (x86, x64, ia64)

Visual Studio 2008 contains Visual C++ 9.0 compiler. Distutils will automatically detect the compiler and use it. The Express edition of Visual Studio 2008 only bundles a compiler for x86.

MinGW (x86)

MinGW is an alternative C++ compiler that works with all Python versions.

• Install Minimalist GNU For Windows into C:\MinGW.

• Open MinGW Installation Manager, check mingw32-base and mingw32-gcc-g++, and Apply Changes in the Installation menu.

• Add C:\MinGW\bin to the PATH environment variable (With ";" before if PATH is not empty).

• Create a distutils.cfg file with the following contents in the folder \Lib\distutils in Python install directory :

   1 [build]
   2 compiler=mingw32
   3 
   4 [build_ext]
   5 compiler=mingw32

Links

• Microsoft : The latest supported Visual C++ downloads : List of up-to-date Visual C++ Redistributable and Visual Studio packages.