Re: THEORY: Allophones

I know we discussed this before, but I have a doubt
concerning allophones and phonetic change rules.
Suppose there's a language allowing a syllable
structure CVF (F = fricative or liquid), where you
can compound roots not necessarily conforming to
CVF, and you have, say,

        /kak/ + /tat/ = /kaxtat/

(there's /x/ in the language independently from the
one related to /k/). Now, what's the /x/ in /kaxtat/,
an allophone of /k/ or merely an /x/ coming from /k/
via a phonetic change rule?


--Pablo Flores