I’ve had mixed results with ccache myself, ending up not using it. Compilation times are much less of a problem for me than they were before, because of the increases in processor power and number of threads. This together with pchs and judicously forward declaring and including only what you use.
From the times Circle surfaces in discussions, I think I remember reading it’s it not being open source that is holding back adoption? Not sure, anyway as a C++ dev i’d love to see one of the different approaches to fundamentally improving C++ take widespread hold.
Such gains by limiting included headers is surprising to me, as it’s the first thing anyone would suggest doing. Clang-tidy hints in QtCreator show warnings for includes that are not used. For me this works pretty well to keep build times due to headers under control. I wonder, if reducing the amount of included headers already yields such significant gains, what other gains can be had, and what LOC we’re talking about. I’ve seen dramatic improvements by using pch for instance. Or isolating boost usage.
ccache folder size started becoming huge. And it just didn’t speed up the project builds, I don’t remember the details of why.
Right, that might have been the reason.
When I tried it I was working on a 100+ devs C++ project, 3/4M LOC, about as big as they come. Compilation of everything from scratch was an hour at the end. Switching to lld was a huge win, as well as going from 12 to compilation 24 threads. The code-base in a way you don’t need to build everything to work on a specific part, using dynamically loaded libraries to inject functionality in the main app.
I was a linux dev there, the pch’s worked, not as well as for MSVC where they made a HUGE difference. Otoh lld blows the microsoft linker out of the water, clean builds were faster on msvc, incremental faster on linux.