Improve CI scripts

[Chocobo1]

• GHA CI: tweak cache size
  It seems ~500MB is enough to cache all the build artifacts but we still make it a bit larger to avoid thrashing.
• GHA CI: shorten Windows CI build time
  Now vcpkg caches b2 tool. Boost doesn't need the exact b2 version to generate the cmake files.

[xavier2k6]

@Chocobo1 Just thought of something If microsoft/vcpkg#42678 gets merged, then that may be problematic for RC_1_2 libtorrent builds due to the deprecations contained in Boost 1.87.0

I've tried to limit macOS in libtorrent RC_1_2 to Boost 1.85.0 but boost-build from homebrew will download 1.87.0 versions leading to issues.
See: arvidn/libtorrent#7896 (WIP)

More context on Boost issue: arvidn/libtorrent#7875

Perhaps a stand-alone release can be used from https://github.com/bfgroup/b2/releases ?

[Chocobo1]

Just thought of something If microsoft/vcpkg#42678 gets merged, then that may be problematic for RC_1_2 libtorrent builds due to the deprecations contained in Boost 1.87.0

Don't worry, it won't affect us. This is like using a newer cmake.exe to run an older CMakeLists.txt which should be compatible.

I've tried to limit macOS in libtorrent RC_1_2 to Boost 1.85.0 but boost-build from homebrew will download 1.87.0 versions leading to issues.
See: arvidn/libtorrent#7896 (WIP)

The PR is different to qbt CI so we won't face the same problem. You could try to limit boost-build to 1.85 in that PR.

More context on Boost issue: arvidn/libtorrent#7875

It will probably never be resolved IMO. Despite the code changes there might be ABI compatibility concerns that comes along.

Perhaps a stand-alone release can be used from https://github.com/bfgroup/b2/releases ?

I checked their releases and they didn't provide a pre-built b2.exe which we required.

[glassez]

I checked their releases and they didn't provide a pre-built b2.exe which we required.

I wonder why we need b2 at all. After all, we use header-only Boost libraries.

[Chocobo1]

I wonder why we need b2 at all. After all, we use header-only Boost libraries.

It is required to generate cmake files.
As for why we need those cmake files from boost source, see: https://cmake.org/cmake/help/latest/policy/CMP0167.html

[userdocs]

As far as I understood this, the header files are in the archive/boost directory and are just copied to a created include when you generate headers and the only time I need to generate headers is when cloning from Github, which I avoid doing unless there is no fallback.

Here is me building with no header generation qbittorrent desktop and nox on Debian based using latest cmake with no issue.

https://github.com/userdocs/qbittorrent-crossbuild/blob/main/.github/workflows/qbittorrent_crossbuild.yml#L247-L248

None of my builds require me to use b2 unless 1: i'm using b2 to build libtorrent or 2: i cloned boost from github.

As far as I can see you do neither of those and could just link to the boost folder. Unless i'm missing something here as to why header are generated.

[Chocobo1]

Here is me building with no header generation qbittorrent desktop and nox on Debian based using latest cmake with no issue.
https://github.com/userdocs/qbittorrent-crossbuild/blob/main/.github/workflows/qbittorrent_crossbuild.yml#L247-L248

BOOST_INCLUDEDIR is from FindBoost module so it will have the same problem as #22315.

[userdocs]

I build with this

https://github.com/userdocs/cmake-crossbuild/releases/tag/3.31.5_1.12.1

If it was removed in 3.30 how can it be the same issue?

[userdocs]

So I removed the BOOST_INCLUDEDIR and set it like this. Without the CMAKE_PREFIX_PATH to the extracted boost archive dir it will fail

https://github.com/userdocs/qbittorrent-crossbuild/blob/main/.github/workflows/qbittorrent_crossbuild.yml#L247

It builds ok https://github.com/userdocs/qbittorrent-crossbuild/actions/runs/13640403413

This would be using policy CMP0167 new, right, and not using FindBoost ?