failed AVER: (NOT (SB-C::CAST-TYPE-CHECK SB-C::NODE))

[Paul F. Dietz]

(defun bug076 (c)
  (declare (notinline - svref))
  (let* ((v1 (svref #(1 3 4 6) 0)))
    (declare (dynamic-extent v1))
    (- c v1)))

==>

failed AVER: (NOT (SB-C::CAST-TYPE-CHECK SB-C::NODE))
[...]
  0: (SB-C::IR2-CONVERT-CAST #<SB-ALIEN:CAST :%TYPE-CHECK :EXTERNAL :VALUE #<SB-C::LVAR 1 {101032F163}> :ASSERTED-TYPE #1=#<SB-KERNEL:NUMERIC-TYPE NUMBER> :TYPE-TO-CHECK #1# {1010332063}> #<SB-C::IR2-BLOCK..
  1: (SB-C::IR2-CONVERT-BLOCK #<SB-C::CBLOCK 2 :START c2 {1010332FC3}>)
  2: (SB-C:IR2-CONVERT #<SB-C:COMPONENT :NAME BUG076 {10103314E3}>)
  3: (SB-C::%COMPILE-COMPONENT #<SB-C:COMPONENT :NAME BUG076 {10103314E3}>)
[...]