[goombacloud]

I think the hard part is to know when caching is not allowed, and for that the compiler is a good point to manage such a cache because it could add metadata such as compiler version (maybe even patches?), compiler flags etc which a wrapper may miss. This disintegration of ccache and the compiler makes me not really trust it because these two could easily get out of sync and you would not easily notice when/why the result is wrong.