Comment 3 for bug 721135

Stas, Thanks for the fix!

I didn't realize the version was that old, but it's what I've got from a not-too-old Ubuntu install. It's a little bit later than the version the original report was filed under at least. This was the bug report I found when searching for the error message, so it's where I posted the output.

On a later version of Ubuntu (which means a debian version of SBCL), I still get the warning:

$ uname -a
Linux hostname 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

CL-USER> (lisp-implementation-version)
"1.1.14.debian"

CL-USER> (lambda ()
           (destructuring-bind (&optional (x nil xp)) '()
             (declare (ignore xp))
             x))
; in: LAMBDA ()
; (IGNORE XP)
;
; caught STYLE-WARNING:
; IGNORE declaration for an unknown variable: XP
;
; compilation unit finished
; caught 1 STYLE-WARNING condition
#<FUNCTION (LAMBDA ()) {100469FD1B}>