/root/xemacs-21.1.4/lisp/files.elc
 
 What's the problem ?
 Error in configure ? 
No. The problem is that files.elc is dumped in. M-x find-function
looks at load-history to see where the file came from. However for
dumped lisp the load-history contains the path at the dump time!
Thanks for spotting this bug.
Jan