The value NIL is not of type SB-C::IR2-BLOCK

[Paul F. Dietz]

(lambda (a)
  (declare (type fixnum a))
  (unwind-protect 0
    (svref #(216424 738192)
           (min 1 (max 0 (case a ((-1 -3 0 -5) a) (t 1)))))))

==>

The value
  NIL
is not of type
  SB-C::IR2-BLOCK
   [Condition of type TYPE-ERROR]

Restarts:
 0: [RETRY] Retry SLIME REPL evaluation request.
 1: [*ABORT] Return to SLIME's top level.
 2: [ABORT] abort thread (#<THREAD tid=5840 "repl-thread" RUNNING {10103880A3}>)

Backtrace:
  0: (SB-C::BLOCK-LABEL #<SB-C::CBLOCK 12 :START c1 {100E576053}>)
  1: (SB-C::PREPARE-JUMP-TABLE-TARGETS #<SB-C::LVAR 2 {100E571443}> ((-1 . #1=#<SB-C::CBLOCK 12 :START c1 {100E576053}>) (-3 . #1#) (0 . #1#) (-5 . #1#) (OTHERWISE . #1#)))
  2: (SB-C::IR2-CONVERT-JUMP-TABLE #<SB-C:JUMP-TABLE :INDEX #<SB-C::LVAR 2 {100E571443}> :TARGETS ((-1 . #1=#<SB-C::CBLOCK 12 :START c1 {100E576053}>) (-3 . #1#) (0 . #1#) (-5 . #1#) (OTHERWISE . #1#)) {10..
  3: (SB-C::IR2-CONVERT-BLOCK #<SB-C::CBLOCK 8 :START c3 {100E514BC3}>)
  4: (SB-C:IR2-CONVERT #<SB-C:COMPONENT :NAME "<unknown>" {100E576373}>)
  5: (SB-C::%COMPILE-COMPONENT #<SB-C:COMPONENT :NAME "<unknown>" {100E576373}>)
  6: (SB-C::COMPILE-COMPONENT #<SB-C:COMPONENT :NAME "<unknown>" {100E576373}>)
  7: (SB-C::%COMPILE (LAMBDA (A) (DECLARE (TYPE FIXNUM A)) (UNWIND-PROTECT 0 (SVREF # #))) NIL NIL)
 [...]

x86-64, "2.4.2.200-8a4a8dd68"