- (bit-xor vec vec t))
-
-;;; The old (pre-1999) code had a more-efficient-looking, but also
-;;; less-portable implementation of CLEAR-BIT-VECTOR:
-;;; (do ((i sb!vm:vector-data-offset (1+ i))
-;;; (end (+ sb!vm:vector-data-offset
-;;; (ash (+ (length vec) (1- sb!vm:n-word-bits))
-;;; (- (1- (integer-length sb!vm:n-word-bits)))))))
-;;; ((= i end) vec)
-;;; (setf (sb!kernel:%raw-bits vec i) 0)))
-;;; We could use this in the target SBCL if the new version turns out to be a
-;;; bottleneck. I (WHN 19990321) will stick to the portable version for now.
-;;; And by the way, if we do revisit this file with efficiency on our mind, it
-;;; might be good to check whether it's really that helpful to implement
-;;; all these functions as INLINE. (How expensive can it be to call a
-;;; 1-argument function? How expensive is it to fill up our cache with
-;;; a bunch of redundant loop expansions?)
-;;;
-;;; FIXME: Perhaps do simple benchmarks against CMU CL to check this.