1 ;;;; This file contains code which knows about both the type
2 ;;;; representation and the compiler IR1 representation. This stuff is
3 ;;;; used for doing type checking.
5 ;;;; This software is part of the SBCL system. See the README file for
8 ;;;; This software is derived from the CMU CL system, which was
9 ;;;; written at Carnegie Mellon University and released into the
10 ;;;; public domain. The software is in the public domain and is
11 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
12 ;;;; files for more information.
14 ;;;; FIXME: This is a poor name for this file, since CTYPE is the name
15 ;;;; of the type used internally to represent Lisp types. It'd
16 ;;;; probably be good to rename this file to "call-type.lisp" or
17 ;;;; "ir1-type.lisp" or something.
21 (declaim (type (or function null) *lossage-fun* *unwinnage-fun* *ctype-test-fun*))
23 ;;; These are the functions that are to be called when a problem is
24 ;;; detected. They are passed format arguments. If null, we don't do
25 ;;; anything. The LOSSAGE function is called when something is
26 ;;; definitely incorrect. The UNWINNAGE function is called when it is
27 ;;; somehow impossible to tell whether the call is correct. (Thus,
28 ;;; they should correspond fairly closely to the FAILURE-P and WARNINGS-P
29 ;;; return values of CL:COMPILE and CL:COMPILE-FILE. However, see the
30 ;;; KLUDGE note below for *LOSSAGE-DETECTED*.)
31 (defvar *lossage-fun*)
32 (defvar *unwinnage-fun*)
34 ;;; the function that we use for type checking. The derived type is
35 ;;; its first argument and the type we are testing against is its
36 ;;; second argument. The function should return values like CSUBTYPEP.
37 (defvar *ctype-test-fun*)
38 ;;; FIXME: Why is this a variable? Explain.
40 ;;; *LOSSAGE-DETECTED* is set when a "definite incompatibility" is
41 ;;; detected. *UNWINNAGE-DETECTED* is set when we can't tell whether the
42 ;;; call is compatible or not. Thus, they should correspond very closely
43 ;;; to the FAILURE-P and WARNINGS-P return values of CL:COMPILE and
44 ;;; CL:COMPILE-FILE.) However...
46 ;;; KLUDGE: Common Lisp is a dynamic language, even if CMU CL was not.
47 ;;; As far as I can see, none of the "definite incompatibilities"
48 ;;; detected in this file are actually definite under the ANSI spec.
49 ;;; They would be incompatibilites if the use were within the same
50 ;;; compilation unit as the contradictory definition (as per the spec
51 ;;; section "3.2.2.3 Semantic Constraints") but the old Python code
52 ;;; doesn't keep track of whether that's the case. So until/unless we
53 ;;; upgrade the code to keep track of that, we have to handle all
54 ;;; these as STYLE-WARNINGs. -- WHN 2001-02-10
55 (defvar *lossage-detected*)
56 (defvar *unwinnage-detected*)
58 ;;; Signal a warning if appropriate and set *FOO-DETECTED*.
59 (declaim (ftype (function (string &rest t) (values)) note-lossage note-unwinnage))
60 (defun note-lossage (format-string &rest format-args)
61 (setq *lossage-detected* t)
63 (apply *lossage-fun* format-string format-args))
65 (defun note-unwinnage (format-string &rest format-args)
66 (setq *unwinnage-detected* t)
68 (apply *unwinnage-fun* format-string format-args))
71 (declaim (special *compiler-error-context*))
73 ;;;; stuff for checking a call against a function type
75 ;;;; FIXME: This is stuff to look at when I get around to fixing
76 ;;;; function type inference and declarations.
78 ;;; A dummy version of SUBTYPEP useful when we want a functional like
79 ;;; SUBTYPEP that always returns true.
80 (defun always-subtypep (type1 type2)
81 (declare (ignore type1 type2))
84 ;;; Determine whether a use of a function is consistent with its type.
85 ;;; These values are returned:
86 ;;; T, T: the call is definitely valid.
87 ;;; NIL, T: the call is definitely invalid.
88 ;;; NIL, NIL: unable to determine whether the call is valid.
90 ;;; The ARGUMENT-TEST function is used to determine whether an
91 ;;; argument type matches the type we are checking against. Similarly,
92 ;;; the RESULT-TEST is used to determine whether the result type
93 ;;; matches the specified result.
95 ;;; Unlike the argument test, the result test may be called on values
96 ;;; or function types. If STRICT-RESULT is true and SAFETY is
97 ;;; non-zero, then the NODE-DERIVED-TYPE is always used. Otherwise, if
98 ;;; CONT's TYPE-CHECK is true, then the NODE-DERIVED-TYPE is
99 ;;; intersected with the CONT's ASSERTED-TYPE.
101 ;;; The error and warning functions are functions that are called to
102 ;;; explain the result. We bind *COMPILER-ERROR-CONTEXT* to the
103 ;;; combination node so that COMPILER-WARNING and related functions
104 ;;; will do the right thing if they are supplied.
105 (defun valid-fun-use (call type &key
106 ((:argument-test *ctype-test-fun*) #'csubtypep)
107 (result-test #'values-subtypep)
109 ((:lossage-fun *lossage-fun*))
110 ((:unwinnage-fun *unwinnage-fun*)))
111 (declare (type function result-test) (type combination call)
112 (type fun-type type))
113 (let* ((*lossage-detected* nil)
114 (*unwinnage-detected* nil)
115 (*compiler-error-context* call)
116 (args (combination-args call))
117 (nargs (length args))
118 (required (fun-type-required type))
119 (min-args (length required))
120 (optional (fun-type-optional type))
121 (max-args (+ min-args (length optional)))
122 (rest (fun-type-rest type))
123 (keyp (fun-type-keyp type)))
126 ((fun-type-wild-args type)
128 (arg args (cdr arg)))
130 (check-arg-type (car arg) *wild-type* i)))
131 ((not (or optional keyp rest))
132 (if (/= nargs min-args)
134 "The function was called with ~R argument~:P, but wants exactly ~R."
136 (check-fixed-and-rest args required nil)))
139 "The function was called with ~R argument~:P, but wants at least ~R."
142 (check-fixed-and-rest args (append required optional) rest))
143 ((not (or keyp rest))
145 "The function was called with ~R argument~:P, but wants at most ~R."
147 ((and keyp (oddp (- nargs max-args)))
149 "The function has an odd number of arguments in the keyword portion."))
151 (check-fixed-and-rest args (append required optional) rest)
153 (check-key-args args max-args type))))
155 (let* ((dtype (node-derived-type call))
156 (return-type (fun-type-returns type))
157 (cont (node-cont call))
159 (if (or (not (continuation-type-check cont))
160 (and strict-result (policy call (/= safety 0))))
162 (values-type-intersection (continuation-asserted-type cont)
164 (multiple-value-bind (int win) (funcall result-test out-type return-type)
166 (note-unwinnage "can't tell whether the result is a ~S"
167 (type-specifier return-type)))
169 (note-lossage "The result is a ~S, not a ~S."
170 (type-specifier out-type)
171 (type-specifier return-type))))))
173 (cond (*lossage-detected* (values nil t))
174 (*unwinnage-detected* (values nil nil))
177 ;;; Check that the derived type of the continuation CONT is compatible
178 ;;; with TYPE. N is the arg number, for error message purposes. We
179 ;;; return true if arg is definitely o.k. If the type is a magic
180 ;;; CONSTANT-TYPE, then we check for the argument being a constant
181 ;;; value of the specified type. If there is a manifest type error
182 ;;; (DERIVED-TYPE = NIL), then we flame about the asserted type even
183 ;;; when our type is satisfied under the test.
184 (defun check-arg-type (cont type n)
185 (declare (type continuation cont) (type ctype type) (type index n))
187 ((not (constant-type-p type))
188 (let ((ctype (continuation-type cont)))
189 (multiple-value-bind (int win) (funcall *ctype-test-fun* ctype type)
191 (note-unwinnage "can't tell whether the ~:R argument is a ~S"
192 n (type-specifier type))
195 (note-lossage "The ~:R argument is a ~S, not a ~S."
196 n (type-specifier ctype) (type-specifier type))
198 ((eq ctype *empty-type*)
199 (note-unwinnage "The ~:R argument never returns a value." n)
202 ((not (constant-continuation-p cont))
203 (note-unwinnage "The ~:R argument is not a constant." n)
206 (let ((val (continuation-value cont))
207 (type (constant-type-type type)))
208 (multiple-value-bind (res win) (ctypep val type)
210 (note-unwinnage "can't tell whether the ~:R argument is a ~
212 n (type-specifier type) val)
215 (note-lossage "The ~:R argument is not a constant ~S:~% ~S"
216 n (type-specifier type) val)
220 ;;; Check that each of the type of each supplied argument intersects
221 ;;; with the type specified for that argument. If we can't tell, then
222 ;;; we can complain about the absence of manifest winnage.
223 (declaim (ftype (function (list list (or ctype null)) (values)) check-fixed-and-rest))
224 (defun check-fixed-and-rest (args types rest)
225 (do ((arg args (cdr arg))
226 (type types (cdr type))
228 ((or (null type) (null arg))
231 (check-arg-type arg rest n)
234 (check-arg-type (car arg) (car type) n))
237 ;;; Check that the &KEY args are of the correct type. Each key should
238 ;;; be known and the corresponding argument should be of the correct
239 ;;; type. If the key isn't a constant, then we can't tell, so we can
240 ;;; complain about absence of manifest winnage.
241 (declaim (ftype (function (list fixnum fun-type) (values)) check-key-args))
242 (defun check-key-args (args pre-key type)
243 (do ((key (nthcdr pre-key args) (cddr key))
244 (n (1+ pre-key) (+ n 2)))
249 ((not (check-arg-type k (specifier-type 'symbol) n)))
250 ((not (constant-continuation-p k))
251 (note-unwinnage "The ~:R argument (in keyword position) is not a ~
255 (let* ((name (continuation-value k))
256 (info (find name (fun-type-keywords type)
257 :key #'key-info-name)))
259 (unless (fun-type-allowp type)
260 (note-lossage "~S is not a known argument keyword."
263 (check-arg-type (second key) (key-info-type info)
267 ;;; Construct a function type from a definition.
269 ;;; Due to the lack of a (LIST X) type specifier, we can't reconstruct
271 (declaim (ftype (function (functional) fun-type) definition-type))
272 (defun definition-type (functional)
273 (if (lambda-p functional)
275 :required (mapcar #'leaf-type (lambda-vars functional))
276 :returns (tail-set-type (lambda-tail-set functional)))
281 (dolist (arg (optional-dispatch-arglist functional))
282 (let ((info (lambda-var-arg-info arg))
283 (type (leaf-type arg)))
285 (ecase (arg-info-kind info)
286 (:required (req type))
287 (:optional (opt type))
289 (keys (make-key-info :name (arg-info-key info)
291 ((:rest :more-context)
292 (setq rest *universal-type*))
301 :keyp (optional-dispatch-keyp functional)
302 :allowp (optional-dispatch-allowp functional)
303 :returns (tail-set-type
305 (optional-dispatch-main-entry functional))))))))
307 ;;;; approximate function types
309 ;;;; FIXME: This is stuff to look at when I get around to fixing function
310 ;;;; type inference and declarations.
312 ;;;; Approximate function types provide a condensed representation of all the
313 ;;;; different ways that a function has been used. If we have no declared or
314 ;;;; defined type for a function, then we build an approximate function type by
315 ;;;; examining each use of the function. When we encounter a definition or
316 ;;;; proclamation, we can check the actual type for compatibity with the
319 (defstruct (approximate-fun-type (:copier nil))
320 ;; the smallest and largest numbers of arguments that this function
321 ;; has been called with.
322 (min-args sb!xc:call-arguments-limit :type fixnum)
323 (max-args 0 :type fixnum)
324 ;; a list of lists of the all the types that have been used in each
326 (types () :type list)
327 ;; A list of APPROXIMATE-KEY-INFO structures describing all the
328 ;; things that looked like &KEY arguments. There are distinct
329 ;; structures describing each argument position in which the keyword
331 (keys () :type list))
333 (defstruct (approximate-key-info (:copier nil))
334 ;; The keyword name of this argument. Although keyword names don't
335 ;; have to be keywords, we only match on keywords when figuring an
337 (name (missing-arg) :type keyword)
338 ;; The position at which this keyword appeared. 0 if it appeared as the
339 ;; first argument, etc.
340 (position (missing-arg) :type fixnum)
341 ;; a list of all the argument types that have been used with this keyword
342 (types nil :type list)
343 ;; true if this keyword has appeared only in calls with an obvious
345 (allowp nil :type (member t nil)))
347 ;;; Return an APPROXIMATE-FUN-TYPE representing the context of
348 ;;; CALL. If TYPE is supplied and not null, then we merge the
349 ;;; information into the information already accumulated in TYPE.
350 (declaim (ftype (function (combination
351 &optional (or approximate-fun-type null))
352 approximate-fun-type)
354 (defun note-fun-use (call &optional type)
355 (let* ((type (or type (make-approximate-fun-type)))
356 (types (approximate-fun-type-types type))
357 (args (combination-args call))
358 (nargs (length args))
359 (allowp (some (lambda (x)
360 (and (constant-continuation-p x)
361 (eq (continuation-value x) :allow-other-keys)))
364 (setf (approximate-fun-type-min-args type)
365 (min (approximate-fun-type-min-args type) nargs))
366 (setf (approximate-fun-type-max-args type)
367 (max (approximate-fun-type-max-args type) nargs))
369 (do ((old types (cdr old))
370 (arg args (cdr arg)))
372 (setf (approximate-fun-type-types type)
375 (list (continuation-type x)))
377 (when (null arg) (return))
378 (pushnew (continuation-type (car arg))
382 (collect ((keys (approximate-fun-type-keys type) cons))
383 (do ((arg args (cdr arg))
385 ((or (null arg) (null (cdr arg)))
386 (setf (approximate-fun-type-keys type) (keys)))
387 (let ((key (first arg))
389 (when (constant-continuation-p key)
390 (let ((name (continuation-value key)))
391 (when (keywordp name)
394 (and (eq (approximate-key-info-name x) name)
395 (= (approximate-key-info-position x)
398 (val-type (continuation-type val)))
401 (approximate-key-info-types old)
404 (setf (approximate-key-info-allowp old) nil)))
406 (keys (make-approximate-key-info
410 :types (list val-type))))))))))))
413 ;;; This is similar to VALID-FUNCTION-USE, but checks an
414 ;;; APPROXIMATE-FUN-TYPE against a real function type.
415 (declaim (ftype (function (approximate-fun-type fun-type
416 &optional function function function)
417 (values boolean boolean))
418 valid-approximate-type))
419 (defun valid-approximate-type (call-type type &optional
421 #'types-equal-or-intersect)
423 #'compiler-style-warn)
424 (*unwinnage-fun* #'compiler-note))
425 (let* ((*lossage-detected* nil)
426 (*unwinnage-detected* nil)
427 (required (fun-type-required type))
428 (min-args (length required))
429 (optional (fun-type-optional type))
430 (max-args (+ min-args (length optional)))
431 (rest (fun-type-rest type))
432 (keyp (fun-type-keyp type)))
434 (when (fun-type-wild-args type)
435 (return-from valid-approximate-type (values t t)))
437 (let ((call-min (approximate-fun-type-min-args call-type)))
438 (when (< call-min min-args)
440 "~:@<The function was previously called with ~R argument~:P, ~
441 but wants at least ~R.~:>"
444 (let ((call-max (approximate-fun-type-max-args call-type)))
445 (cond ((<= call-max max-args))
446 ((not (or keyp rest))
448 "~:@<The function was previously called with ~R argument~:P, ~
449 but wants at most ~R.~:>"
451 ((and keyp (oddp (- call-max max-args)))
453 "~:@<The function was previously called with an odd number of ~
454 arguments in the keyword portion.~:>")))
456 (when (and keyp (> call-max max-args))
457 (check-approximate-keywords call-type max-args type)))
459 (check-approximate-fixed-and-rest call-type (append required optional)
462 (cond (*lossage-detected* (values nil t))
463 (*unwinnage-detected* (values nil nil))
466 ;;; Check that each of the types used at each arg position is
467 ;;; compatible with the actual type.
468 (declaim (ftype (function (approximate-fun-type list (or ctype null))
470 check-approximate-fixed-and-rest))
471 (defun check-approximate-fixed-and-rest (call-type fixed rest)
472 (do ((types (approximate-fun-type-types call-type) (cdr types))
474 (arg fixed (cdr arg)))
476 (let ((decl-type (or (car arg) rest)))
477 (unless decl-type (return))
478 (check-approximate-arg-type (car types) decl-type "~:R" n)))
481 ;;; Check that each of the call-types is compatible with DECL-TYPE,
482 ;;; complaining if not or if we can't tell.
483 (declaim (ftype (function (list ctype string &rest t) (values))
484 check-approximate-arg-type))
485 (defun check-approximate-arg-type (call-types decl-type context &rest args)
486 (let ((losers *empty-type*))
487 (dolist (ctype call-types)
488 (multiple-value-bind (int win) (funcall *ctype-test-fun* ctype decl-type)
491 (note-unwinnage "can't tell whether previous ~? ~
492 argument type ~S is a ~S"
495 (type-specifier ctype)
496 (type-specifier decl-type)))
498 (setq losers (type-union ctype losers))))))
500 (unless (eq losers *empty-type*)
501 (note-lossage "~:(~?~) argument should be a ~S but was a ~S in a previous call."
502 context args (type-specifier decl-type) (type-specifier losers))))
505 ;;; Check the types of each manifest keyword that appears in a keyword
506 ;;; argument position. Check the validity of all keys that appeared in
507 ;;; valid keyword positions.
509 ;;; ### We could check the APPROXIMATE-FUN-TYPE-TYPES to make
510 ;;; sure that all arguments in keyword positions were manifest
512 (defun check-approximate-keywords (call-type max-args type)
513 (let ((call-keys (approximate-fun-type-keys call-type))
514 (keys (fun-type-keywords type)))
516 (let ((name (key-info-name key)))
517 (collect ((types nil append))
518 (dolist (call-key call-keys)
519 (let ((pos (approximate-key-info-position call-key)))
520 (when (and (eq (approximate-key-info-name call-key) name)
521 (> pos max-args) (evenp (- pos max-args)))
522 (types (approximate-key-info-types call-key)))))
523 (check-approximate-arg-type (types) (key-info-type key) "~S" name))))
525 (unless (fun-type-allowp type)
526 (collect ((names () adjoin))
527 (dolist (call-key call-keys)
528 (let ((pos (approximate-key-info-position call-key)))
529 (when (and (> pos max-args) (evenp (- pos max-args))
530 (not (approximate-key-info-allowp call-key)))
531 (names (approximate-key-info-name call-key)))))
533 (dolist (name (names))
534 (unless (find name keys :key #'key-info-name)
535 (note-lossage "Function previously called with unknown argument keyword ~S."
538 ;;;; ASSERT-DEFINITION-TYPE
540 ;;; Intersect LAMBDA's var types with TYPES, giving a warning if there
541 ;;; is a mismatch. If all intersections are non-null, we return lists
542 ;;; of the variables and intersections, otherwise we return NIL, NIL.
543 (defun try-type-intersections (vars types where)
544 (declare (list vars types) (string where))
546 (mapc (lambda (var type)
547 (let* ((vtype (leaf-type var))
548 (int (type-approx-intersection2 vtype type)))
550 ((eq int *empty-type*)
552 "Definition's declared type for variable ~A:~% ~S~@
553 conflicts with this type from ~A:~% ~S"
554 (leaf-debug-name var) (type-specifier vtype)
555 where (type-specifier type))
556 (return-from try-type-intersections (values nil nil)))
560 (values vars (res))))
562 ;;; Check that the optional-dispatch OD conforms to Type. We return
563 ;;; the values of TRY-TYPE-INTERSECTIONS if there are no syntax
564 ;;; problems, otherwise NIL, NIL.
566 ;;; Note that the variables in the returned list are the actual
567 ;;; original variables (extracted from the optional dispatch arglist),
568 ;;; rather than the variables that are arguments to the main entry.
569 ;;; This difference is significant only for &KEY args with hairy
570 ;;; defaults. Returning the actual vars allows us to use the right
571 ;;; variable name in warnings.
573 ;;; A slightly subtle point: with keywords and optionals, the type in
574 ;;; the function type is only an assertion on calls --- it doesn't
575 ;;; constrain the type of default values. So we have to union in the
576 ;;; type of the default. With optionals, we can't do any assertion
577 ;;; unless the default is constant.
579 ;;; With keywords, we exploit our knowledge about how hairy keyword
580 ;;; defaulting is done when computing the type assertion to put on the
581 ;;; main-entry argument. In the case of hairy keywords, the default
582 ;;; has been clobbered with NIL, which is the value of the main-entry
583 ;;; arg in the unsupplied case, whatever the actual default value is.
584 ;;; So we can just assume the default is constant, effectively
585 ;;; unioning in NULL, and not totally blow off doing any type
587 (defun find-optional-dispatch-types (od type where)
588 (declare (type optional-dispatch od)
591 (let* ((min (optional-dispatch-min-args od))
592 (req (fun-type-required type))
593 (opt (fun-type-optional type)))
594 (flet ((frob (x y what)
597 "The definition has ~R ~A arg~P, but ~A has ~R."
599 (frob min (length req) "fixed")
600 (frob (- (optional-dispatch-max-args od) min) (length opt) "optional"))
601 (flet ((frob (x y what)
604 "The definition ~:[doesn't have~;has~] ~A, but ~
605 ~A ~:[doesn't~;does~]."
607 (frob (optional-dispatch-keyp od) (fun-type-keyp type)
609 (unless (optional-dispatch-keyp od)
610 (frob (not (null (optional-dispatch-more-entry od)))
611 (not (null (fun-type-rest type)))
613 (frob (optional-dispatch-allowp od) (fun-type-allowp type)
614 "&ALLOW-OTHER-KEYS"))
616 (when *lossage-detected*
617 (return-from find-optional-dispatch-types (values nil nil)))
621 (let ((keys (fun-type-keywords type))
622 (arglist (optional-dispatch-arglist od)))
623 (dolist (arg arglist)
625 ((lambda-var-arg-info arg)
626 (let* ((info (lambda-var-arg-info arg))
627 (default (arg-info-default info))
628 (def-type (when (constantp default)
629 (ctype-of (eval default)))))
630 (ecase (arg-info-kind info)
632 (let* ((key (arg-info-key info))
633 (kinfo (find key keys :key #'key-info-name)))
636 (res (type-union (key-info-type kinfo)
637 (or def-type (specifier-type 'null)))))
640 "Defining a ~S keyword not present in ~A."
642 (res *universal-type*)))))
643 (:required (res (pop req)))
645 (res (type-union (pop opt) (or def-type *universal-type*))))
647 (when (fun-type-rest type)
648 (res (specifier-type 'list))))
650 (when (fun-type-rest type)
651 (res *universal-type*)))
653 (when (fun-type-rest type)
654 (res (specifier-type 'fixnum)))))
656 (when (arg-info-supplied-p info)
657 (res *universal-type*)
658 (vars (arg-info-supplied-p info)))))
664 (unless (find (key-info-name key) arglist
666 (let ((info (lambda-var-arg-info x)))
668 (arg-info-key info)))))
670 "The definition lacks the ~S key present in ~A."
671 (key-info-name key) where))))
673 (try-type-intersections (vars) (res) where))))
675 ;;; Check that Type doesn't specify any funny args, and do the
677 (defun find-lambda-types (lambda type where)
678 (declare (type clambda lambda) (type fun-type type) (string where))
679 (flet ((frob (x what)
682 "The definition has no ~A, but the ~A did."
684 (frob (fun-type-optional type) "&OPTIONAL arguments")
685 (frob (fun-type-keyp type) "&KEY arguments")
686 (frob (fun-type-rest type) "&REST argument"))
687 (let* ((vars (lambda-vars lambda))
688 (nvars (length vars))
689 (req (fun-type-required type))
691 (unless (= nvars nreq)
692 (note-lossage "The definition has ~R arg~:P, but the ~A has ~R."
694 (if *lossage-detected*
696 (try-type-intersections vars req where))))
698 ;;; Check for syntactic and type conformance between the definition
699 ;;; FUNCTIONAL and the specified FUN-TYPE. If they are compatible
700 ;;; and REALLY-ASSERT is T, then add type assertions to the definition
701 ;;; from the FUN-TYPE.
703 ;;; If there is a syntactic or type problem, then we call
704 ;;; LOSSAGE-FUN with an error message using WHERE as context
705 ;;; describing where FUN-TYPE came from.
707 ;;; If there is no problem, we return T (even if REALLY-ASSERT was
708 ;;; false). If there was a problem, we return NIL.
709 (defun assert-definition-type
710 (functional type &key (really-assert t)
711 ((:lossage-fun *lossage-fun*)
712 #'compiler-style-warn)
714 (where "previous declaration"))
715 (declare (type functional functional)
716 (type function *lossage-fun*)
718 (unless (fun-type-p type)
719 (return-from assert-definition-type t))
720 (let ((*lossage-detected* nil))
721 (multiple-value-bind (vars types)
722 (if (fun-type-wild-args type)
724 (etypecase functional
726 (find-optional-dispatch-types functional type where))
728 (find-lambda-types functional type where))))
729 (let* ((type-returns (fun-type-returns type))
730 (return (lambda-return (main-entry functional)))
732 (continuation-asserted-type (return-result return)))))
734 ((and atype (not (values-types-equal-or-intersect atype
737 "The result type from ~A:~% ~S~@
738 conflicts with the definition's result type assertion:~% ~S"
739 where (type-specifier type-returns) (type-specifier atype))
741 (*lossage-detected* nil)
742 ((not really-assert) t)
745 (assert-continuation-type (return-result return) atype))
746 (loop for var in vars and type in types do
747 (cond ((basic-var-sets var)
748 (when (and unwinnage-fun
749 (not (csubtypep (leaf-type var) type)))
750 (funcall unwinnage-fun
751 "Assignment to argument: ~S~% ~
752 prevents use of assertion from function ~
754 (leaf-debug-name var)
756 (type-specifier type))))
758 (setf (leaf-type var) type)
759 (dolist (ref (leaf-refs var))
760 (derive-node-type ref type)))))
763 (defun check-catch-tag-type (tag)
764 (declare (type continuation tag))
765 (let ((ctype (continuation-type tag)))
766 (when (csubtypep ctype (specifier-type '(or number character)))
767 (compiler-style-warn "~@<using ~S of type ~S as a catch tag (which ~
768 tends to be unportable because THROW and CATCH ~
769 use EQ comparison)~@:>"
770 (continuation-source tag)
771 (type-specifier (continuation-type tag))))))