Bug in CL with destructuring-bind and default arguments

Hello,

I've noticed a bug in CL with destructuring-bind:

This should work:

(destructuring-bind (&optional (a 1)) '() a)

But instead it gives an error:

Debugger entered--Lisp error: (void-variable bind-enquote)
  cl-do-arglist((&optional (a 1)) 'nil)
  #[(args expr &rest body) "ƉƉÇȆ