Greetings, Lennart was asking but LLVM does have a c library implementation, linker and debugger currently. While most inexperienced toolchain developers or people building one assume you have to use all GCC or LLVM excluding the c library that's not the case. A lot of people use lld, LLVM's linker with GCC due to it being much faster.  For a traditional toolchain you require: 1. Compiler 2. Linker 3. C Library 4. Kernel Headers 5. Probably a Debugger Therefore you can select or take what you want from each of 1,2,3,5 from either LLVM or GCC. There has been lots of work on the LLVM and GCC sides to make sure it works well and still is. If your going to ask me questions please CC the list so others can get the info as well, Nick