What are the minimum clang/llvm tools needed to compile, link, and create a library ?
It depends what you mean with these terms.
Assuming “compile” means “starting from C/C++” to “binary object”, then you need clang.
If “link” is what takes multiple “binary objects” and generate a “platform specific executable" or a "shared library”, then we have lld, even though it is not totally ready for production (it seems that Elf and COFF are quite complete).
If “create a library” is about creating a "shared library” then it is part of the link usually. If you’re interested into static archive, we provide llvm-ar and llvm-ranlib.