Internal define-syntax isn't resolved correctly

[Takashi Kato]

Following script should return 0 but raises and error.

(let ()
  (define-syntax bind-to-zero
    (syntax-rules ()
      ((bind-to-zero id) (define id (zero)))))
  (bind-to-zero x)
  (define-syntax zero (syntax-rules () ((_) 0)))
  x)

[Takashi Kato]

Probably bb52de0 resolved this.