A possible macro (let-syntax) bug

I've made a test case to show a strange warning message I got. The code works in chicken and larceny scheme but not sagittarius.

x.sld:

(define-library (x)
  (import (scheme base) (scheme write))
  (export example-1 example-2)
  (begin

    (define-syntax begin-scope
      (syntax-rules ()
    ((begin-scope defer <body> ...)
     (let ((stuff '()))
       (let-syntax ((defer (syntax-rules ()
                 ((defer <statement>)
                  (set! stuff (cons <statement> stuff))
                  ))))
         (begin <body> ...))
       (for-each display stuff)))))

    (define (example-1)
      (begin-scope defer
           (display "one")
           (display "two")
           (display "three")))

    (define (example-2)
      (begin-scope defer
           (display "one")
           (defer (display "two"))
           (display "three")))))

Then loading it:

$ rlwrap sagittarius -c -L. -S.sld
sash> (import (x))
WARNING: reference to undefined variable: 'stuff' in (x)
WARNING: reference to undefined variable: 'stuff' in (x)
#<unspecified>
sash> (example-1)
onetwothree#<unspecified>
sash> (example-2)
onetwo*error*

It looks like the let-syntax was not able to capture the variable "stuff" to make use of.

I hope this report is useful!

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