dev-ruby/commonmarker-2.1.1 fails to build if llvm-core/clang is not installed: ... thread 'main' panicked at /var/tmp/portage/dev-ruby/commonmarker-2.1.1/work/cargo_home/gentoo/bindgen-0.69.5/lib.rs:622:31: Unable to find libclang: "couldn't find any valid shared libraries matching: ['libclang.so', 'libclang-*.so', 'libclang.so.*', 'libclang-*.so.*'], set the `LIBCLANG_PATH` environment variable to a path where one of these files can be found (invalid: [])" note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace ^[[1m^[[33mwarning^[[0m^[[1m:^[[0m build failed, waiting for other jobs to finish... make: *** [Makefile:566: target/release/libcommonmarker.so] Error 101 make: Leaving directory '/var/tmp/portage/dev-ruby/commonmarker-2.1.1/work/ruby32/commonmarker-2.1.1/ext/commonmarker' ^[[31;01m*^[[0m ERROR: dev-ruby/commonmarker-2.1.1::gentoo failed (compile phase): ^[[31;01m*^[[0m emake failed ... Manually emerging llvm-core/clang first (tested with 20.1.3:20/20.1 but I don't know that it matters) will make building dev-ruby/commonmarker-2.1.1 succeed.