Download newer LLVM version from kernel.org

The product page for the version of Ubuntu used in the manifest says: Reached end of standard support on 31 May 2025, maybe we could use a newer version, like the latest 26.04, and then we can use LLVM 22 directly from the repo?
https://packages.ubuntu.com/resolute/llvm-22

Also add ccache (can be useful for incremental build)

That would be interesting, but do we have any storage persistence right now? (no harm in adding it now in any case)

The product page for the version of Ubuntu used in the manifest says: Reached end of standard support on 31 May 2025, maybe we could use a newer version, like the latest 26.04, and then we can use LLVM 22 directly from the repo?

Did the runtime update in #3 but 25.10 doesn't have a new enough LLVM. If somebody can figure out what the locales problem is, we get llvm22 for free.

Did the runtime update in #3 but 25.10 doesn't have a new enough LLVM. If somebody can figure out what the locales problem is, we get llvm22 for free.

Looks like installing locales separately works, so, llvm22 for free?

As noted in bluez/action-ci#4 this will likely need Clang 23 in the future, so it's probably better to just go download the version we want instead of sticking with distro packages

Also add ccache (can be useful for incremental build)

That would be interesting, but do we have any storage persistence right now? (no harm in adding it now in any case)

There's no caching infrastructure but iirc the incremental build rebuilds in same instance

I cannot merge this one it seems, anyway we probably need to transfer this to bluez org if it is still a dependency.

I see, we are still using this in Dockerfile:

Dockerfile:FROM blueztestbot/bluez-build:latest

Let us move it over to bluez/docker or something like that.

Updated to the LLVM 23 prerelease from kernel.org