xyzzy の loop マクロの while の評価順がおかしい

gistfile1.cl

;; xyzzy 0.2.2.235
(require "cmu_loop")
(loop
  for i from 0 to 2
  while (progn
          (format t "while ~A~%" i)
          t)
  do (format t "do ~A~%" i))
do 0
while 1
do 1
while 2
do 2
while 3
nil

gistfile2.cl

;; clisp 2.48

[1]> (loop
  for i from 0 to 2
  while (progn
          (format t "while ~A~%" i)
          t)
  do (format t "do ~A~%" i))
while 0
do 0
while 1
do 1
while 2
do 2
NIL

gistfile3.cl

;; SBCL 1.0.37

* (loop
  for i from 0 to 2
  while (progn
          (format t "while ~A~%" i)
          t)
  do (format t "do ~A~%" i))
while 0
do 0
while 1
do 1
while 2
do 2
NIL
*