Comment 1 for bug 309091

simple test case (works as expected on ccl and allegro):

(let ((fname "/tmp/a"))
  ;; touch
  (with-open-file (s fname :direction :output :if-exists :supersede)
    (format s "hello~%"))
  ;; supersede
  (catch 'hi
    (with-open-file (s fname :direction :output :if-exists :supersede)
      (format s "hi~%")
      (throw 'hi nil)))
  ;; check still exists
  (assert (probe-file fname)) ;; <=== it was deleted:-{
  (with-open-file (s fname)
    (assert (equal "hello" (read-line s)))
    t))