Aaron Ballman

Also, as a related question: are the build instructions accurate that compilation requires VS 2013 or *older*? If so, it would be nice to update so that the project can...

> are you sure this is a thing that should be SFINAE? Looks like it, but would be good to have some words from the spec that confirm it. http://eel.is/c++draft/temp.deduct#general-8...

Fixed by https://github.com/llvm/llvm-project/commit/6ed21fc515230ac2ea459d8aa90566e9a467bbb0

> @AaronBallman may comment on the state of K&R function definitions. They were removed for C2x ([WG14 N2841](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2841.htm) and [WG14 N2432](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2432.pdf)) which is just coming up to the Committee Draft...

> Yes, I understand that the proposed change is to make the K&R syntax obsolete. K&R C functions have *always* been obsolete (see C89 3.9.5p1: "The use of function definitions...

> Those functions do in fact each have a prototype using the ISO format that precede the K&R declaration. So they are not functions without a prototype. [citation needed] (I...

I don't know that I have more to add to the conversation to try to clarify the situation, so I'll bow out at this point.

FWIW, I'm unaware of any policy that we try to avoid adding things to `-Wextra`. It's definitely true that our `-Wextra` and GCC's differ, but I think that's due to...

I think this request subsumes D51545, so there should be no need to resurrect that review. That one was looking to add just the tautological constant comparison warnings to `-Wextra`...

Any `JoinedOrSeparate` flag will have this problem. If the flag has a longer name, it's not such a big deal because it's unlikely to show up as a prefix. But...