`bytevector-length' doesn't accept a shared array from a bytevector

[Diogo F. S. Ramos]

I want to take the length of a shared array, but `bytevector-length'
throws an error claiming the shared array isn't a bytevector, even
though it prints the error argument as one.

--8<---------------cut here---------------start------------->8---
scheme@(guile-user)> ,use (rnrs bytevectors)
scheme@(guile-user)> (bytevector-length 
                      (make-shared-array (make-bytevector 42)
                                         list
                                         7))
ERROR: In procedure bytevector-length:
ERROR: In procedure scm_c_bytevector_length: Wrong type argument in position 1 
(expecting bytevector): #vu8(0 0 0 0 0 0 0)

Entering a new prompt.  Type `,bt' for a backtrace or `,q' to continue.
scheme@(guile-user) [1]>
--8<---------------cut here---------------end--------------->8---

I am using Guile 2.0.11, Debian Stable package 2.0.11+1-9.