I use ccache and love it, but I keep wondering: wouldn’t it make more sense for compilers to do caching themselves? That would allow them to cache the results of much finer-grained operations than whole translation units. If two (or 500!) translation units generate the same template instantiations and then each optimize that code, that has to happen in each translation unit and ccache can’t help; couldn’t a compiler with internal caching do it once and be done with it forever? I’ve considered trying to add this to clang, but haven’t prioritized it.