feat: relax the minimum CMake version requirement

[windowsair]

Using a newer version like cmake 3.21 (2022-06) is too aggressive. Let's downgrade cmake to the original 3.11 version.

[OlivierLDff]

Thing is, FetchContent_Populate has been introduced in CMake 3.14. CPM is requiring cmake 3.14 too. So I guess we can go there. I don't think 3.21 is too new anyway, it's fairly easy to upgrade cmake and shouldn't break anything. What is your use case and why you need to downgrade?

[OlivierLDff]

Can you add in the CI a matrix to test CMake 3.14, latest (I don't think 3.11 will work), I recommend using https://github.com/lukka/get-cmake

[windowsair]

As easy as it is to upgrade, using a lower version of cmake in order to provide an out of the box experience is also important.

As an example, Ubuntu 20.04 provides a cmake of 3.16, while Visual Studio 2019 provides cmake as 3.20.

Maybe setting the minimum version to 3.14 is a good idea?

[windowsair]

Can you add in the CI a matrix to test CMake 3.14, latest (I don't think 3.11 will work), I recommend using https://github.com/lukka/get-cmake

Sure. Or we can just use the action app for that: https://github.com/marketplace/actions/actions-setup-cmake

Do I need to add it to this PR?

[OlivierLDff]

Yes we want the PR to pass the tests, so you can add everything here.

I think I prefer https://github.com/marketplace/actions/get-cmake (for sentimental reason, not very technical):

• I'm using it in other projects, it has been working for years, never breaking.
• It has more star
• It has been most recently updated

Again I don't know what are the difference with the other project exactly.

[windowsair]

Tested on CMake 3.14, 3.24, latestrc. Everything looks great except for a bunch of CI matrix.

      matrix:
        use_cpm: ['ON', 'OFF']
        build_type: ['Release']
        os: [ubuntu-latest, macos-latest, windows-latest]
        cmake_version: [3.14, 3.24, latestrc]

Do we need such kind of CI update?

[windowsair]

Okay, let's start by modifying the minimal version.

[OlivierLDff]

Yes we want to enforce in the CI that everything works. I guess CMake version can be tested only on ubuntu-latest, using include statement (https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstrategymatrixinclude)

[windowsair]

I found that cmake 3.14 on Windows needs to specify the PATH address manually, otherwise cmake can't find cl.exe.

If you only care about Ubuntu, I will upload a new modification

[OlivierLDff]

Yes because we want to test if the cmake code is working with 3.14, windows not finding cl.exe sound like a bug from an old version and we don't really care about testing that.

[windowsair]

It makes sense. The commit now is a possible implementation. CI looks like working fine.

[OlivierLDff]

Sorry for taking so much time to merge, you never requested a review again so I lost track of the PR status. Thanks for the contribution