Looks like CMake fails to build due too misplaced `__config_site` header for libc++. It is at: ``` /cgnutools/include/x86_64-pc-linux-musl/c++/v1/ ``` But shold be here with `__config` ``` /cgnutools/include/c++/v1/ ``` For a work around, just use links: ``` ln -sv ../../x86_64-pc-linux-musl/c++/v1/__config_site /cgnutools/include/c++/v1/__config_site ln -sv ../../x86_64-pc-linux-musl/c++/v1/module.modulemap cgnutools/include/c++/v1/module.modulemap ```