define-record-type with custom protocol on parent doesn't raise an error

[Takashi Kato]

This should raise an error but it'll be runtime error

#!r6rs
(import (rnrs))

(define-record-type this-parent
  (fields count elements)
  (protocol
   (lambda (p)
     (lambda (size)
       (p size (make-vector size))))))
;; error
(define-record-type child
  (fields attr)
  (parent this-parent))

[Takashi Kato]

Adding has-protocol? slot to record-constructor-descriptor. Checking if parent has custom protocol or not (Fixes #118)

→ <<cset 77989427982a>>