+ ;; KLUDGE: All this ASH optimization is suppressed under CMU CL for
+ ;; some bignum cases because as of version 2.4.6 for Debian and 18d,
+ ;; CMU CL blows up on (ASH 1000000000 -100000000000) (i.e. ASH of
+ ;; two bignums yielding zero) and it's hard to avoid that
+ ;; calculation in here.
+ #+(and cmu sb-xc-host)
+ (when (and (or (typep (numeric-type-low n-type) 'bignum)
+ (typep (numeric-type-high n-type) 'bignum))
+ (or (typep (numeric-type-low shift) 'bignum)
+ (typep (numeric-type-high shift) 'bignum)))
+ (return-from ash-derive-type-aux *universal-type*))