GCC front-ends

GCC front-ends

I found the LLVM tutorial excellent when I was going through it recently - I got a working AOT compiler for a tiny subset of Python going in a couple of hours.

This is the opposite of what you're looking for, to be fair; I wanted to use LLVM's compilation backend with a non-C language, and you wanted to use Clang's C parser. But there is a libclang tutorial that looks brief and readable that might be what you wanted. (Perhaps it did not exist at the time.)