;;;; The message a handler for a parent reads lives in context/temp, so it is
;;;; good until the frame ends, not only while the clause runs: [why] hands it
;;;; back to its caller, which writes over the stack before printing it. Kept
;;;; past (free-temp) without a clone, a dev build has poisoned it with
;;;; 0xDEADBEEF, so its first byte is one of that pattern's; a release build
;;;; still has "(" there.

(defstruct MyErr :parent Error [code i32])

(defn why [] string
  (handler-case (do (error (MyErr {.code 3})) "")
    [(Error [e] (.message e))]))

(defn scribble [n i32] i64
  (let [junk (array-fill [64] (i64 n))]
    (if (= n 0) (at junk 3) (+ (at junk 5) (scribble (- n 1))))))

(defn main [] i32
  (let [m (why)]
    (scribble 40)
    (println m))
  (let [m (why)]
    (free-temp)
    (let [b (at (bytes-view m) 0)]
      (println (or (= b (u8 0xEF)) (= b (u8 0xBE)) (= b (u8 0xAD))
                   (= b (u8 0xDE))))))
  0)