structure constructor in defconstant

From advice from list I found that the following will cause a compile
error when the call to defconstant is added:

-----------start

(defstruct (point (:conc-name nil))
  x y z)

(setq s (make-point :x 1 :y 2 :z 3))


(defconstant eye (make-point :x 0 :y 0 :z 200))


-----------stop

The error:

-----------start

keithr@katana:~$ lisp
CMU Common Lisp CVS 19d 19d-release (19D), running on katana
With core: /usr/lib/cmucl/lisp.core
Dumped on: Fri, 2007-09-28 23:45:25-05:00 on katana
For support see http://www.cons.org/cmucl/support.html Send bug
reports to the debian BTS.
or to [email protected]
type (help) for help, (quit) to exit, and (demo) to see the demos

Loaded subsystems:
    Python 1.1, target Intel x86
    CLOS based on Gerd's PCL 2004/04/14 03:32:47
* (compile-file "rt4.lisp")

; Python version 1.1, VM version Intel x86 on 28 OCT 07 01:39:03 pm.
; Compiling: /home/keithr/rt4.lisp 28 OCT 07 01:38:34 pm

; Byte Compiling Top-Level Form:
; Converted MAKE-POINT.
; Compiling DEFSTRUCT POINT:

Error in KERNEL:%COERCE-TO-FUNCTION:  the function MAKE-POINT is undefined.
   [Condition of type UNDEFINED-FUNCTION]

Restarts:
  0: [ABORT] Return to Top-Level.

Debug  (type H for help)

(KERNEL:%COERCE-TO-FUNCTION MAKE-POINT)
Source:
; File: target:code/fdefinition.lisp
(FDEFN-OR-LOSE NAME)
0]


---------stop