CMake: remove obsolete references to files generated by scons

[Be-ing]

No description provided.

[daschuer]

The files are still there on a developers machine.

[Be-ing]

If someone still has old files on their machine that they have not cleaned up, that is their problem. That's not relevant to cpack which is executed on GH Actions always in a new VM.

[daschuer]

This file is not only used by GitHub actions.
These extra lines do not hurt.

[Be-ing]

What else uses these lines besides GitHub Actions?

[uklotzde]

Developers are supposed to start the build from a clean checkout. We are not able to exclude any unknown files that might still lay around in the local file system. The common exclude patterns in CPACK_SOURCE_IGNORE_FILES are an acceptable exception.

The only alternative would be to explicitly define all files/patterns that should be included in the set. That would be my preferred approach to avoid unintended inclusions.

[daschuer]

That is slightly different here. If you switch from to 2.2 and back the files are there.
These extra lines are helpful and do not hurt.

[Be-ing]

By that logic we should still have these files in .gitignore but we have already removed those.

[daschuer]

Ups ... I see that was done here: #2777
We may consider to revert this turns out to be an issue.

[Be-ing]

Considering nobody has complained, I think there is no issue. It is unlikely anyone would accidentally commit scons files to 2.3 because they would be untracked files that would have to be intentionally staged. For CPack it is very unlikely to be a problem because CPack only needs to be run by GH Actions. There is no need for developers to run CPack locally unless they are working on packaging.

[Holzhaus]

That is slightly different here. If you switch from to 2.2 and back the files are there.
These extra lines are helpful and do not hurt.

I thought we already decided that we don't want another 2.2 release. Is this really an issue?

[daschuer]

It is probably no real issue but it is extremely annoying if the huge cache directory is packed, running your system out of space.
Compared to this keeping the ignore lines are also no issue.

[Be-ing]

You are more likely to notice the build artifacts from 2.2 if they are not in .gitignore so they show up as untracked files in git status.

[Be-ing]

ping

[daschuer]

Let's close this. These lines are still helpful. The issue is, if one still has these file and likes to keep them, he as to re-add them and exclude his changes from commits. This is unlike a .git-ignore, where a user version exists that can be used. This is annoying. This comes with the cost of just three extra lines visual clutter.
There is no extra maintenance, because we will always need to maintain an exclude region in the CMakeList.txt

• cache -> a biiiig directory, duplicate it will likely eat up all HD
• *_build -> or old recommend cmake build folder, some users might not yet have moved to build, because there is no pressing reason
• .sconf_temp -> we never want to see this folder in a package

[uklotzde]

Let's separate those lines from the rest and leave a comment to remove them after some grace period, e.g. branching 2.4.0 beta

[github-actions]

This PR is marked as stale because it has been open 90 days with no activity.

[Be-ing]

We now have a stable release without SCons. I don't think there's any reason to keep this legacy code.

[daschuer]

OK, now that the 2.2 branch is no longer relevant the risk of problems after merging this is marginal. LGTM