I would completely agree with you if this weren't a C compiler project. In this case, the advantage of having a self-hosting compiler is huge! Among other things, you can use the compiler source itself to test the compiler, which is pretty cool.
I have worked on projects that were essentially "C with classes," and it was fine. I'm not saying every C++ project needs to go all out using every feature from C++ 11, but I didn't even see much beyond use of the string class here. It seems not worth giving up self-hosting to me.
> the advantage of having a self-hosting compiler is huge!
I agree that it's kind of neat to compile your compiler with itself, but it's not clear to me that this constitutes a significant productivity boost. There are countless other C programs that have already been written and can be used as test cases.
So I'm left wondering what the huge advantage that self-hosting provides is. I am interested so, if you have more to say on the topic, I will certainly read it.
If we're talking about toy compilers and learning, then productivity isn't really in consideration. Having a self-hosting compiler for a non-trivial language means you've achieved the "bootstrap" stage, which is a significant milestone and really gives you a practical understanding of what's involved in developing a programming language. A compiler that is powerful enough to compile itself is on the way to exiting the "toy"/"theoretical" realm that most people who study compilers don't ever go beyond.
I have worked on projects that were essentially "C with classes," and it was fine. I'm not saying every C++ project needs to go all out using every feature from C++ 11, but I didn't even see much beyond use of the string class here. It seems not worth giving up self-hosting to me.