On Fri, 14 Aug 2020 at 08:39, Christian Ledergerber <christian.lederger...@ecorobotix.com> wrote: > > I have created the following issue for cmake to launch the discussion: > https://gitlab.kitware.com/cmake/cmake/-/issues/21092
When you described your idea I didn't think you meant making changes for incorporation in the upstream CMake software but to some local CMake version. I think that it will be hard to implement it in a generic enough way for CMake since 1. The solution will require a specific ccache version to work at all. 2. The method of using ccache to probe whether clang-tidy should be run won't work for users who don't use warnings-as-errors. Also, how would CMake know that warnings-as-errors is used? It could be part of WarningsAsErrors in the config file or it could be on the command line but only for some warnings, etc. Sounds brittle and complex. 3. The method is also brittle since the clang-tidy step will be skipped if the source is built (and therefore cached) by a normal non-clang-tidy build. (But if you apply your changes to a local CMake version you can make any assumptions you want, of course.) I spontaneously think that it would be a better idea to either (a) stop running clang-tidy for a normal build and instead run it as a special build once in a while, or (b) improve https://github.com/ejfitzgerald/clang-tidy-cache if you find it deficient in some way (I know nothing about it), or (c) implement clang-tidy support in ccache or another compiler cache program. Just a comment on your CMake GitLab issue: > 2. Add Class.clang-tidy to configuration of extra_files_to_hash of ccache > using the command line syntax: --set-config=KEY=VALUE see > https://ccache.dev/manual/latest.html That's not a good idea. --set-config is just a convenience alternative to manually editing the ccache configuration file. If you run it once for each compilation you will have race conditions between invocations and you will mess up the user's ccache configuration. To enable some ccache setting for a specific compilation you should set the corresponding environment variable, i.e. CCACHE_EXTRAFILES in this case. -- Joel _______________________________________________ ccache mailing list ccache@lists.samba.org https://lists.samba.org/mailman/listinfo/ccache
