[Sbcl-help] WARNING: Asserted type REAL conflicts with derived type ???

[Pascal J.B. <pj...@in...>]

With SBCL 0.8.7, while compiling a file containing the following
function:
  
(DEFUN PARSE-ADDRESS (COMMAND POSITION)
  ;;address -->   '.' | '$' | number
  ;;            | '-' | '^' | '-' number | '^' number
  ;;                  | '+' | '+' number | space number
  ;;                  | '/' re '/' | '?' re '?' | '//' | '??'
  ;;                  | "'" lc .
  (declare (integer position))
  (LET ((ADDRESS NIL) (CH))
    (FLET ((PARSE-OPTIONAL-NUMBER
            ()
            (SETQ POSITION (SKIP-SPACES COMMAND (1+ POSITION)))
            (WHEN (AND POSITION
                       (SETQ CH (CHAR COMMAND POSITION))
                       (DIGIT-CHAR-P CH))
              (MULTIPLE-VALUE-BIND (VALUE POS)
                  (PARSE-INTEGER COMMAND :START POSITION :JUNK-ALLOWED T)
                (WHEN VALUE
                  (SETQ ADDRESS (CONS ADDRESS VALUE)))
                (SETQ POSITION POS)))))
      (SETQ POSITION (SKIP-SPACES COMMAND POSITION))
      (WHEN POSITION
        (SETQ CH (CHAR COMMAND POSITION))
        (COND
         ((CHAR= CH (CHARACTER ".")) (SETQ ADDRESS :CURR) (INCF POSITION))
         ((CHAR= CH (CHARACTER "$")) (SETQ ADDRESS :LAST) (INCF POSITION))
         ((DIGIT-CHAR-P CH)
          (MULTIPLE-VALUE-BIND (VALUE POS)
              (PARSE-INTEGER COMMAND :START POSITION :JUNK-ALLOWED T)
            (WHEN VALUE
              (SETQ ADDRESS (CONS :LINUM VALUE)))
            (SETQ POSITION POS)))
         ((OR (CHAR= CH (CHARACTER "^")) (CHAR= CH (CHARACTER "-")))
          (SETQ ADDRESS :PREV)
          (PARSE-OPTIONAL-NUMBER))
         ((OR (CHAR= CH (CHARACTER " ")) (CHAR= CH (CHARACTER "+")))
          (SETQ ADDRESS :NEXT)
          (PARSE-OPTIONAL-NUMBER))
         ((OR (CHAR= CH (CHARACTER "/")) (CHAR= CH (CHARACTER "?")))
          ;; TODO: regexp
          ;; eat regexp:
          (SETQ ADDRESS
                (CONS :REGEXP 
                      (DO ((TERMINATOR CH)
                           (END POSITION (1+ END)))
                          ((OR (>= END (LENGTH COMMAND)
                                   (CHAR= TERMINATOR (CHAR COMMAND END))))
                           (declare (integer end))
                           (PROG1 (SUBSEQ COMMAND POSITION (1+ END))
                             (SETQ POSITION (1+ END))))))))
         ((CHAR= CH (CHARACTER "'"))
          (INCF POSITION)
          ;; TODO: when there is an error here it's: "Invalid mark character"
          ;; TODO: not: "Invalid address" !
          (WHEN (< POSITION (LENGTH COMMAND))
            (SETQ ADDRESS (CONS :MARK (CHAR COMMAND POSITION)))
            (INCF POSITION)))
         )))
    (VALUES ADDRESS POSITION))


I get this error:


; compiling DEFUN PARSE-ADDRESS: 

; file: /local/users/pascal/src/common/common-lisp/ed.lisp
; in: DEFUN PARSE-ADDRESS
;     (>= COM.INFORMATIMAGO.COMMON-LISP.ED::END
;       (LENGTH COM.INFORMATIMAGO.COMMON-LISP.ED::COMMAND)
;       (CHAR= COM.INFORMATIMAGO.COMMON-LISP.ED::TERMINATOR
;              (CHAR COM.INFORMATIMAGO.COMMON-LISP.ED::COMMAND
;                    COM.INFORMATIMAGO.COMMON-LISP.ED::END)))
; ==>
;   ((LAMBDA (#:G1208 #:G1207 #:G1206)
;      (DECLARE (TYPE REAL #:G1208 #:G1207 #:G1206))
;      (IF (< #:G1208 #:G1207) NIL (IF # NIL T)))
;    COM.INFORMATIMAGO.COMMON-LISP.ED::END
;    (LENGTH COM.INFORMATIMAGO.COMMON-LISP.ED::COMMAND)
;    (CHAR= COM.INFORMATIMAGO.COMMON-LISP.ED::TERMINATOR
;           (CHAR COM.INFORMATIMAGO.COMMON-LISP.ED::COMMAND
;                 COM.INFORMATIMAGO.COMMON-LISP.ED::END)))
; 
; caught WARNING:
;   Asserted type REAL conflicts with derived type
;   (VALUES (MEMBER T NIL) &OPTIONAL).


What is the problem exactly?  I don't handle any floating-point value
in this program.



-- 
__Pascal Bourguignon__                     http://www.informatimago.com/

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