bcain added inline comments.
================ Comment at: clang/CMakeLists.txt:179-183 +if(DEFAULT_SYSROOT) + message(WARNING "DEFAULT_SYSROOT is deprecated and will be removed. Use " + "configuration files (https://clang.llvm.org/docs/UsersManual.html#configuration-files)" + "to specify the default --sysroot=") +endif() ---------------- MaskRay wrote: > bcain wrote: > > At one time I believe that the clang configuration files could not specify > > paths relative to the clang executable. AFAICT `DEFAULT_SYSROOT` does > > support this. > > > > But if I'm mistaken about that can we add an example to the docs at > > https://clang.llvm.org/docs/UsersManual.html#configuration-files > > illustrating how to use a relative sysroot? > Clang configuration files just complement user-specified command line > options. As one can do `--sysroot=./sysroot`, one can add > `--sysroot=./sysroot` to a configuration file, too. > > If you think having a sysroot example is useful, I can add > > ``` > # Relative --sysroot > --sysroot=./sysroot > ``` > before > clang/docs/UsersManual.rst:1018 `-c --target=x86_64-unknown-linux-gnu` IIUC: when clang takes a `--sysroot=./sysroot` argument, it will interpret that path as a prefix to the files it wants to access. So the system will treat it as relative to the environment's `cwd`, correct? But when `DEFAULT_SYSROOT` is set to a relative path, that relative path is considered to be relative to `clang`. Therefore a convenient feature that we take advantage of is setting it to something like `../target/hexagon-unknown-linux-musl` in order to have anyone who invokes `hexagon-unknown-linux-clang` from any path be able to find the includes and libraries distributed with the toolchain without having to specify the sysroot. Maybe there's a better way to achieve this without the need for a relative `DEFAULT_SYSROOT` but it's been very useful and the config files do not seem suited to replace it. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D158218/new/ https://reviews.llvm.org/D158218 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits