Warning from unreachable code

[Paul F. Dietz]

 (lambda (a) (if a 0 (complex a 0)))

==>

; in: LAMBDA (A)
; (COMPLEX CL-TEST::A 0)
;
; caught WARNING:
; Derived type of A is
; (VALUES NULL &OPTIONAL),
; conflicting with its asserted type
; REAL.
; See also:
; The SBCL Manual, Node "Handling of Types"
;
; compilation unit finished
; caught 1 WARNING condition
#<FUNCTION (LAMBDA (A)) {53989D5B}>

May be a duplicate of bug 309451

[Stas Boukarev (stassats)]

But it is reachable?

[Paul F. Dietz (paul-f-dietz)]

True. This is a bad report. Invalid.