Tail Recursion in Common Lisp ???

["Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>]

    I don't recall any suggestion that the current definition of Common Lisp
    does not allow tail-recursion optimization.  How could a language
    definition possibly disallow it?

OK, it was suggested that it was illegal to optimize a function that
calls itself tail-recursively into a simple iteration that just jumps
back to the start of the current function without checking for
redefinition of the function in the meantime.  The discussion was not
about the legality of doing the jump instead of a full recursive call,
but about whether the check was required.

-- Scott