THAW branch: The value #<SB-C::OPTIONAL-DISPATCH ...> is not of type SB-C::CLAMBDA when binding SB-C::NEW-FUN

[Paul F. Dietz]

This was found on SB's thaw branch, which he asked me to test. The failure occurred quickly in random testing (within 50K iterations).

(defun f313 (b c)
  (flet ((%f (&key (k 0))
            (return-from %f
               (flet ((%g (x y &optional (z b)) z))
                 (%g (%g 0 c) 0 0))))))
  0)

==>

The value
  #<SB-C::OPTIONAL-DISPATCH
    :%SOURCE-NAME %G
    :%DEBUG-NAME #1=(FLET %G :IN F313)
    :TYPE #2=#<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)>
    :WHERE-FROM :DEFINED
    :ARGLIST (#<SB-C::LAMBDA-VAR :%SOURCE-NAME X {1005043DE3}>
              #<SB-C::LAMBDA-VAR :%SOURCE-NAME Y {1005043EA3}>
              #<SB-C::LAMBDA-VAR
                :%SOURCE-NAME Z
                :ARG-INFO #<SB-C::ARG-INFO
                            :KIND :OPTIONAL
                            :DEFAULT B {1005044043}> {1005043F63}>)
    :ALLOWP NIL
    :KEYP NIL
    :MIN-ARGS 2
    :MAX-ARGS 3
    :ENTRY-POINTS (#<SB-C::CLAMBDA
                     :%SOURCE-NAME SB-C::.ANONYMOUS.
                     :%DEBUG-NAME (SB-C::&OPTIONAL-PROCESSOR
                                   (FLET %G :IN F313))
                     :KIND NIL
                     :TYPE #2#
                     :WHERE-FROM :DEFINED
                     :VARS (X Y) {1005045073}>
                   #3=#<SB-C::CLAMBDA
                        :%SOURCE-NAME %G
                        :%DEBUG-NAME #1#
                        :KIND :OPTIONAL
                        :TYPE #2#
                        :WHERE-FROM :DEFINED
                        :VARS (X Y Z) {1005044353}>)
    :MAIN-ENTRY #3# {1005044133}>

is not of type
  SB-C::CLAMBDA
when binding SB-C::NEW-FUN
   [Condition of type TYPE-ERROR]

Restarts:
 0: [ABORT] Exit debugger, returning to top level.

Backtrace:
  0: (SB-C::MERGE-TAIL-SETS #<SB-C::COMBINATION :FUN #<SB-C::REF :LEAF #<SB-C::OPTIONAL-DISPATCH :%SOURCE-NAME %G :%DEBUG-NAME # :TYPE #<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)> :WHERE-FROM :DEFI..
  1: (SB-C::DELETE-FILTER #<SB-EXT:EXIT :ENTRY #<SB-C::ENTRY {10050438C3}> :VALUE #<SB-C::LVAR 1 {1005043A53}> {1005043AB3}> #<SB-C::LVAR 2 {1005042DB3}> #<SB-C::LVAR 1 {1005043A53}>)
  2: (SB-C::MERGE-LETS #<SB-C::CLAMBDA :%SOURCE-NAME SB-C::.ANONYMOUS. :%DEBUG-NAME (SB-C::&OPTIONAL-PROCESSOR (FLET %G :IN F313)) :KIND NIL :TYPE #<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)> :WHERE..
  3: (SB-C::LET-CONVERT #<SB-C::CLAMBDA :%SOURCE-NAME SB-C::.ANONYMOUS. :%DEBUG-NAME (SB-C::&OPTIONAL-PROCESSOR (FLET %G :IN F313)) :KIND NIL :TYPE #<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)> :WHER..
  4: (SB-C::MAYBE-LET-CONVERT #<SB-C::CLAMBDA :%SOURCE-NAME SB-C::.ANONYMOUS. :%DEBUG-NAME (SB-C::&OPTIONAL-PROCESSOR (FLET %G :IN F313)) :KIND NIL :TYPE #<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)>..
  5: ((FLET SB-C::FROB :IN SB-C::DELETE-OPTIONAL-DISPATCH) #<SB-C::CLAMBDA :%SOURCE-NAME SB-C::.ANONYMOUS. :%DEBUG-NAME (SB-C::&OPTIONAL-PROCESSOR (FLET %G :IN F313)) :KIND NIL :TYPE #<SB-KERNEL:BUILT-IN-C..
  6: (SB-C::DELETE-OPTIONAL-DISPATCH #<SB-C::OPTIONAL-DISPATCH :%SOURCE-NAME %G :%DEBUG-NAME #1=(FLET %G :IN F313) :TYPE #2=#<SB-KERNEL:BUILT-IN-CLASSOID FUNCTION (read-only)> :WHERE-FROM :DEFINED :ARGLIST..

[...]

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

Additional lambda forms that showed the bug (not hand reduced):

   (LAMBDA (A B)
     (DECLARE (TYPE (INTEGER -2124124 105032712075782512) A))
     (DECLARE (TYPE (INTEGER -635 190) B))
     (DECLARE (IGNORABLE A B))
     (DECLARE
      (OPTIMIZE (DEBUG 2) (SPEED 0) (SAFETY 0) (SPACE 3)
       (SB-C:INSERT-STEP-CONDITIONS 0) (COMPILATION-SPEED 0)))
     (LET ((*S6* 0))
       (LET ((*S2*
              (LABELS ((%F4 (&OPTIONAL (F4-1 0) &KEY &ALLOW-OTHER-KEYS)
                         (FLET ((%F15 (F15-1 F15-2 F15-3)
                                  (FLET ((%F15 (F15-1 F15-2 F15-3)
                                           (PROGV
                                               '(*S8* *S9*)
                                               (LIST 0 0)
                                             (FLET ((%F14
                                                        (F14-1 F14-2 F14-3
                                                         &OPTIONAL
                                                         (F14-4 F15-2)
                                                         (F14-5 0) (F14-6 B)
                                                         &KEY (KEY1 0) (KEY2 0))
                                                      F14-3))
                                               (%F14 0 0
                                                (%F14 0 0 (%F14 0 0 0) 0) 0
                                                0)))))
                                    (LET ((*S6* (%F15 0 0 *S6*)))
                                      0))))
                           (%F15 F4-1 0 B))))
                B)))
         0)))

and

   (LAMBDA (A B)
     (DECLARE (TYPE (INTEGER -521801 534917) A))
     (DECLARE (TYPE (INTEGER 4126244932124 6604041512606) B))
     (DECLARE (IGNORABLE A B))
     (DECLARE
      (OPTIMIZE (SB-C:INSERT-STEP-CONDITIONS 0) (DEBUG 1) (SPACE 0) (SPEED 1)
       (COMPILATION-SPEED 2) (SAFETY 3)))
     (FLET ((%F14 (F14-1 F14-2 F14-3 &KEY)
              (RETURN-FROM %F14
                (RETURN-FROM %F14
                  (RETURN-FROM %F14
                    (PROGV
                        '(*S2* *S9* *S3*)
                        (LIST 0 A 0)
                      (LABELS ((%F6 (F6-1 &OPTIONAL (F6-2 F14-1))
                                 F14-2))
                        (%F6 0 (%F6 F14-1)))))))))
       0))

(where the *...* variables are declaimed special.)

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

Another simple one:

(defun f314 (a b)
  (unwind-protect
      (flet ((%f4 (f4-1 f4-2 f4-3 &optional (f4-4 b) (f4-5 0) (f4-6 b) &key)
               0))
        (%f4 a 0 b 0 0 (%f4 a 0 0)))))

[Stas Boukarev (stassats)]

Thanks. Try again, from the same branch.