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Your example isn't exactly true. Clang and GCC both do tail call optimizations. Compiling language functions to C functions doesn't 100% preclude you from TCO. http://david.wragg.org/blog/2014/02/c-tail-calls-1.html

It looks like work/research in this area has been going on for at least ~20 years.

Indeed it has. For a few more examples, see also http://www.ustream.tv/recorded/43777177, and http://www.ccs.neu.edu/racket/pubs/stackhack4.html. Pyret (http://pyret.org) uses similar stack techniques to these to simulate an arbitrarily deep stack while compiling to JS.

It will, otherwise semantics will depend on which C compiler is available and ANSI C doesn't require TCO.