anchor.diff:                  ;; character arrays are special.
                   (not (eql upgraded-element-type 'character)))
              ;; Create a simple 1D array.
  -           (let ((array (if initial-element-p
  -                            (make-simple-array (first dimensions) element-type area initial-element)
  -                            (make-simple-array (first dimensions) element-type area))))
  +           (let ((array (make-simple-array (first dimensions) element-type-info area initial-element initial-element-p)))
                (when initial-contents-p
                  (initialize-from-initial-contents array initial-contents))
                array))
  
positive.code:   ;; n => (n)
    (when (not (listp dimensions))
      (setf dimensions (list dimensions)))
    (let ((rank (length dimensions))
          (upgraded-element-type (upgraded-array-element-type element-type)))
      (when (>= rank array-rank-limit)
        (error "Array has too many dimensions."))
      (when (and initial-element-p initial-contents-p)
  
negative.code:          (array-element-type (%complex-array-storage array)))
          (t ;; Normal arrays use the type of their storage simple array.
           (%simple-array-element-type (%complex-array-storage array)))))
  
  (defun array-element-info (array)
    (check-type array array)
    (cond ((%simple-1d-array-p array)
           (%simple-array-info array))
          ((character-array-p array)
           *array-character-info*)
          ((fixnump (%complex-array-storage array))
           ;; Memory arrays have their type in the info field.
           (upgraded-array-info (svref *array-types* (%complex-array-info array))))
          ((%complex-array-info array)
           ;; Displaced arrays inherit the type of the array they displace on.
           (array-element-type (%complex-array-storage array)))
          (t ;; Normal arrays use the type of their storage simple array.
           (%simple-array-info (%complex-array-storage array)))))
  
  (defun array-has-fill-pointer-p (array)
    (check-type array array)
  