Building and using gn with MinGW on Windows

At the time of writing: 2024-04-13 Test environment: Windows 11, intel x86_64 CPU

Requirements

1. Install MSYS2
2. Start a Terminal windows for MSYS2's MinGW development by opening one of clang32.exe, clang64.exe, clangarm64.exe,mingw32.exe, mingw64.exe, ucrt64.exe.
3. To download clang toolchain, Ninja and git programs, run command: pacman -S mingw-w64-clang-x86_64-toolchain mingw-w64-clang-x86_64-ninja git

Build gn

1. To clone gn source code, run command: git clone https://gn.googlesource.com/gn
2. Run command: cd gn
3. Run command: build/gen.py --platform mingw
   This configuration generates a static executable that does not depend on MSYS2, and can be run in any development environment.
   Use --help flag to check more configuration options.
   Use --allow-warning flag to build with warnings.
4. Run command: ninja -C out

Testing

1. Run command: out/gn --version
2. Run command: out/gn_unittests

Notes:

For "mingw-w64-clang-x86_64-toolchain" in the clang64 environment, g++ is a copy of clang++.

The toolchain that builds gn does not use vendor lock-in compiler command flags, so gn can be built with these clang++, g++.

However the build rules in examples/simple_build require GCC-specific compiler macros, and thus only work in the ucrt64 MSYS2 development environment.