I don't think he's being tongue in cheek. I bet you he's genuinely angry and resentful. From his point of view, he once had a lovely language, C*, and he can't use it any more, and is being forced into assembly instead, for no reason other than the perversity of the maintainers of the only two C compilers that he feels that he can use.
I don't have enough karma to get a down vote button. Even if I did, I'm not sure that voting on your own posts is allowed. I up voted you instead.
Yes, the title is a play on the llvm post. I could be wrong about this, but the way I took it was like this:
"No, don't you presume to tell me what I need to know about undefined behavior. I am your customer, and here's what you need to know about me. Stop treating me like an enemy."
But you could be right. I'm bad enough at detecting jokes and sarcasm in person with people I know. Over a textual medium with a stranger, I don't really trust myself much.