I admit that I didn't read the actual article. :) I was using "library" in a broad sense, just to mean the runtime code that you didn't have to write yourself.
C doesn't exactly have "runtime code that you didn't have to write yourself" though. There's libc, but you can easily disable it, and having any form of defer be unavailable then is just bad. Everything else comes from your code, the headers it includes (which don't contain function definitions), and statically linked things.
Sure. And just like libc, you could easily disable (by not using) a theoretical libc_defer that provided defer semantics. Kind of like libm, you use it when you need it.
This has been a fun conversation, and I really enjoyed chatting with you about this. :) Take care.