305 add ccache to linux build

[dabele]

Changes and Information

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.23%. Comparing base (575a146) to head (5c47821). Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #994   +/-   ##
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  Coverage   96.23%   96.23%           
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  Files         128      128           
  Lines       10852    10852           
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  Hits        10443    10443           
  Misses        409      409           

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[mknaranja]

@dabele Who has been involved here and who is supposed to do the review?

[dabele]

@dabele Who has been involved here and who is supposed to do the review?

it's not done yet. but I need the CI to run for testing this, so it's not a draft.

[dabele]

A little off topic, but does this already help with the boost dependency, or do we need another solution for that? It currently takes up a lot of CI time, both for the download itself as well as for packing and transferring artifacts, as these pack the entire build directory.

Sadly, this doesn't help with that. I though about caching boost, but this would only be possible if the same bootstrapped boost is usable by all builds (or at least all builds of the same operating system family). boost is more than 1G, so if every build needs it's own cached version this will exceed the limit. This will only help with the download and bootstrap phase of boost, not sure what could be done about the artifact size. I guess only saving artifacts that are really required, i.e. test executables and shared objects.