MinGW64 C Compiler

A monkey patch for cygwinccompiler which enables you to use MinGW-w64 as the default compiler on Windows.

If you want to try Cython but doesn't have MSVC installed, this is for you.

WARNING: This project is not widely tested and is only for hobby.

Usage

pip install git+https://github.com/imba-tjd/mingw64ccompiler
python -m mingw64ccompiler install_specs  # ① Run once
python -m mingw64ccompiler install        # ② Run in every venv

Then python setup.py build_ext -i, cythonize -i, mypyc, pip wheel ., pip install --no-build-isolation will use gcc as the default compiler, and it would link with ucrt.

To programmally patch, use __import__('mingw64ccompiler').patch(). This doesn't require you to use install command firstly, but cythonize and other CLI tools won't work.

To use -Wall rather than -O3, set MINGW64CCOMPILER_DEBUG environment variable.

How it works

• ① Create a spec file in mingw installation dir to let gcc link with ucrt. This may not work. This is not required if your mingw is compiled with --with-default-msvcrt=ucrt.
• ② Use sitecustomize.py to overriede the return value of get_default_compiler() so that the default compiler is gcc.

Limitation

• unknown conversion type character 'z' in format when using from cpython cimport array
• I have never used Anaconda and know nothing about it

Known to fail

• psutil: giampaolo/psutil#330
• lxml: Could not find function xmlCheckVersion in library libxml2. Is libxml2 installed?
• llvmlite: requires cmake
• numpy: mt19937.h:27:1: error: multiple storage classes in declaration specifiers
• scipy: BLAS & LAPACK libraries need to be installed
• pyodbc: it sets MSVC-specific args in setup.py
• pytorch extension: when IS_WINDOWS, all compiler related code is set to use MSVC

Reference

• https://stackoverflow.com/questions/57528555/how-do-i-build-against-the-ucrt-with-mingw-w64
• https://github.com/cython/cython/wiki/CythonExtensionsOnWindows#less-useful-information