+;;; bug 31 turned out to be a manifestation of non-ANSI array type
+;;; handling, fixed by CSR in sbcl-0.7.3.8.
+(defun array-element-type-handling (x)
+ (declare (type (vector cons) x))
+ (when (consp (aref x 0))
+ (aref x 0)))
+(assert (eq (array-element-type-handling
+ (make-array 3 :element-type t :initial-element 0))
+ nil))
+