> it could be that you end up compiling a function with, like 30 arguments, or 30 return values; I don’t trust a C compiler to reliably shuffle between different stack argument needs at tail calls to or from such a function.

Yet you trust it to generate the frame for this leviathan in the first place. Sometimes C is about writing quality code, apparently, sometimes it's about spending all day trying to outsmart the compiler rather than take advantage of it.