Is there a guide on how to configure CMake with MinGW/MSYS and git on Windows?

Usage
1

Hi all,

I am a maintainer of a library (OpenXLSX) and have recently augmented the CMake configuration to auto-pull dependencies via find_package or FetchContent from their source repositories, instead of including a copy of the dependencies with our own library.

I have been asking one of our Windows users to test a new configuration for me, and it seems to be non-trivial to get git working for FetchContent.

On their configuration, CMake complains about not finding git.

As this is a generic “getting started” problem:

Is there a comprehensive guide on installing CMake on Windows so that integration with git is working & commands like FetchContent can be used?

I have no access to a Windows test system, so I can’t trial & error a solution for this.

Any help is appreciated so I can instruct our users on how to prepare their CMake for building OpenXLSX.

Cheers!

2

Do you mean building under MinGW/MSYS or working under windows with git for windows?

See Using CMake in MSYS2 - MSYS2

3

With you phrasing this as an “or” question - are you saying that CMake on Windows runs without MinGW?

My question, reduced to the simplest form is:

“How do Windows users install CMake so that it can build projects whose CMake configuration invokes FetchContent commands?”

with the implication being that - as per the observed errors - FetchContent uses git in the background, and CMake in the install that my user reported a test from, does not “find” git.

4

That depends on what they want todo?

What is your build system and what os target system?

And what is the toolchain you want to use?

5

The key is to use a consistent MinGW environment, not MSYS or Git Bash.

Install via MSYS2:

  • mingw-w64-x86_64-cmake

  • mingw-w64-x86_64-toolchain

  • git

Then run everything from the MinGW64 shell:

cmake -G Ninja ..
cmake --build .

FetchContent works out of the box as long as Git is available in PATH.

Avoid mixing MSYS, MinGW, and Git Bash—they use different environments and will break detection.

6

Your last bullet list sounds like what I am looking for, and reasonably to the point.
Regarding your prior comment: I don’t understand the question about the build system - it’s CMake, hence me posting here :slight_smile: The target system for Windows users is the system on which the build is taking place, i.e. also Windows.

For the toolchain: I would assume both work, gcc/g++ or MSVC, but I have no experience with MSVC (nor do I intend to ever touch it), so let’s focus on g++ for starters.

I will see if one of our users can test the installation sequence you proposed:

  • install MSYS2
  • via MSYS2, install
    • mingw-w64-x86_64-cmake
    • mingw-w64-x86_64-toolchain
    • git
  • run cmake from the mingw64 shell (without ninja, which I assume you wrote as an example)