3 Bugs can be reported on the help mailing list
4 sbcl-help@lists.sourceforge.net
5 or on the development mailing list
6 sbcl-devel@lists.sourceforge.net
8 Please include enough information in a bug report that someone reading
9 it can reproduce the problem, i.e. don't write
10 Subject: apparent bug in PRINT-OBJECT (or *PRINT-LENGTH*?)
11 PRINT-OBJECT doesn't seem to work with *PRINT-LENGTH*. Is this a bug?
13 Subject: apparent bug in PRINT-OBJECT (or *PRINT-LENGTH*?)
14 In sbcl-1.2.3 running under OpenBSD 4.5 on my Alpha box, when
15 I compile and load the file
16 (DEFSTRUCT (FOO (:PRINT-OBJECT (LAMBDA (X Y)
17 (LET ((*PRINT-LENGTH* 4))
20 then at the command line type
22 the program loops endlessly instead of printing the object.
27 There is also some information on bugs in the manual page and
28 in the TODO file. Eventually more such information may move here.
30 The gaps in the number sequence belong to old bug descriptions which
31 have gone away (typically because they were fixed, but sometimes for
32 other reasons, e.g. because they were moved elsewhere).
35 KNOWN BUGS OF NO SPECIAL CLASS:
38 DEFSTRUCT almost certainly should overwrite the old LAYOUT information
39 instead of just punting when a contradictory structure definition
40 is loaded. As it is, if you redefine DEFSTRUCTs in a way which
41 changes their layout, you probably have to rebuild your entire
42 program, even if you know or guess enough about the internals of
43 SBCL to wager that this (undefined in ANSI) operation would be safe.
46 ANSI specifies that a type mismatch in a structure slot
47 initialization value should not cause a warning.
49 This one might not be fixed for a while because while we're big
50 believers in ANSI compatibility and all, (1) there's no obvious
51 simple way to do it (short of disabling all warnings for type
52 mismatches everywhere), and (2) there's a good portable
53 workaround. ANSI justifies this specification by saying
54 The restriction against issuing a warning for type mismatches
55 between a slot-initform and the corresponding slot's :TYPE
56 option is necessary because a slot-initform must be specified
57 in order to specify slot options; in some cases, no suitable
59 In SBCL, as in CMU CL (or, for that matter, any compiler which
60 really understands Common Lisp types) a suitable default does
61 exist, in all cases, because the compiler understands the concept
62 of functions which never return (i.e. has return type NIL, e.g.
63 ERROR). Thus, as a portable workaround, you can use a call to
64 some known-never-to-return function as the default. E.g.
66 (BAR (ERROR "missing :BAR argument")
67 :TYPE SOME-TYPE-TOO-HAIRY-TO-CONSTRUCT-AN-INSTANCE-OF))
69 (DECLAIM (FTYPE () NIL) MISSING-ARG)
70 (DEFUN REQUIRED-ARG () ; workaround for SBCL non-ANSI slot init typing
71 (ERROR "missing required argument"))
73 (BAR (REQUIRED-ARG) :TYPE TRICKY-TYPE-OF-SOME-SORT)
74 (BLETCH (REQUIRED-ARG) :TYPE TRICKY-TYPE-OF-SOME-SORT)
75 (N-REFS-SO-FAR 0 :TYPE (INTEGER 0)))
76 Such code will compile without complaint and work correctly either
77 on SBCL or on a completely compliant Common Lisp system.
80 bogus warnings about undefined functions for magic functions like
81 SB!C::%%DEFUN and SB!C::%DEFCONSTANT when cross-compiling files
82 like src/code/float.lisp. Fixing this will probably require
83 straightening out enough bootstrap consistency issues that
84 the cross-compiler can run with *TYPE-SYSTEM-INITIALIZED*.
85 Instead, the cross-compiler runs in a slightly flaky state
86 which is sane enough to compile SBCL itself, but which is
87 also unstable in several ways, including its inability
88 to really grok function declarations.
91 The "byte compiling top-level form:" output ought to be condensed.
92 Perhaps any number of such consecutive lines ought to turn into a
93 single "byte compiling top-level forms:" line.
96 The way that the compiler munges types with arguments together
97 with types with no arguments (in e.g. TYPE-EXPAND) leads to
98 weirdness visible to the user:
99 (DEFTYPE FOO () 'FIXNUM)
101 (TYPEP 11 '(FOO)) => T, which seems weird
102 (TYPEP 11 'FIXNUM) => T
103 (TYPEP 11 '(FIXNUM)) signals an error, as it should
104 The situation is complicated by the presence of Common Lisp types
105 like UNSIGNED-BYTE (which can either be used in list form or alone)
106 so I'm not 100% sure that the behavior above is actually illegal.
107 But I'm 90+% sure, and the following related behavior,
109 treating the bare symbol AND as equivalent to '(AND), is specifically
110 forbidden (by the ANSI specification of the AND type).
113 It would be nice if the
115 (during macroexpansion)
116 said what macroexpansion was at fault, e.g.
118 (during macroexpansion of IN-PACKAGE,
119 during macroexpansion of DEFFOO)
122 (SUBTYPEP '(FUNCTION (T BOOLEAN) NIL)
123 '(FUNCTION (FIXNUM FIXNUM) NIL)) => T, T
124 (Also, when this is fixed, we can enable the code in PROCLAIM which
125 checks for incompatible FTYPE redeclarations.)
128 from DTC on the CMU CL mailing list 25 Feb 2000:
129 ;;; Compiler fails when this file is compiled.
131 ;;; Problem shows up in delete-block within ir1util.lisp. The assertion
132 ;;; (assert (member (functional-kind lambda) '(:let :mv-let :assignment)))
133 ;;; fails within bind node branch.
135 ;;; Note that if c::*check-consistency* is enabled then an un-reached
136 ;;; entry is also reported.
139 (declare (values nil))
156 (let ((ttt #'(lambda () (go cccc))))
157 (declare (special ttt))
158 (return-from bbbb nil))
161 (return-from bbbb nil))))))
164 (I *think* this is a bug. It certainly seems like strange behavior. But
165 the ANSI spec is scary, dark, and deep..)
166 (FORMAT NIL "~,1G" 1.4) => "1. "
167 (FORMAT NIL "~3,1G" 1.4) => "1. "
170 from Marco Antoniotti on cmucl-imp mailing list 1 Mar 2000:
172 (setf (find-class 'ccc1) (find-class 'ccc))
173 (defmethod zut ((c ccc1)) 123)
174 DTC's recommended workaround from the mailing list 3 Mar 2000:
175 (setf (pcl::find-class 'ccc1) (pcl::find-class 'ccc))
178 The ANSI spec, in section "22.3.5.2 Tilde Less-Than-Sign: Logical Block",
179 says that an error is signalled if ~W, ~_, ~<...~:>, ~I, or ~:T is used
180 inside "~<..~>" (without the colon modifier on the closing syntax).
181 However, SBCL doesn't do this:
182 * (FORMAT T "~<munge~wegnum~>" 12)
187 When too many files are opened, OPEN will fail with an
188 uninformative error message
189 error in function OPEN: error opening #P"/tmp/foo.lisp": NIL
190 instead of saying that too many files are open.
193 Right now, when COMPILE-FILE has a read error, it actually pops
194 you into the debugger before giving up on the file. It should
195 instead handle the error, perhaps issuing (and handling)
196 a secondary error "caught ERROR: unrecoverable error during compilation"
197 and then return with FAILURE-P true,
200 reported by Sam Steingold on the cmucl-imp mailing list 12 May 2000:
201 Also, there is another bug: `array-displacement' should return an
202 array or nil as first value (as per ANSI CL), while CMUCL declares
203 it as returning an array as first value always.
204 (Actually, I think the old CMU CL version in SBCL never returns NIL,
205 i.e. it's not just a declaration problem, but the definition doesn't
209 Sometimes (SB-EXT:QUIT) fails with
210 Argh! maximum interrupt nesting depth (4096) exceeded, exiting
211 Process inferior-lisp exited abnormally with code 1
212 I haven't noticed a repeatable case of this yet.
215 some sort of bug in inlining and RETURN-FROM in sbcl-0.6.5: Compiling
218 (BLOCK USED-BY-SOME-Y?
221 (UNLESS (REJECTED? Y)
222 (RETURN-FROM USED-BY-SOME-Y? T)))))
223 (DECLARE (INLINE FROB))
228 error in function SB-KERNEL:ASSERT-ERROR:
229 The assertion (EQ (SB-C::CONTINUATION-KIND SB-C::CONT) :BLOCK-START) failed.
230 This is still present in sbcl-0.6.8.
233 In some cases the compiler believes type declarations on array
234 elements without checking them, e.g.
235 (DECLAIM (OPTIMIZE (SAFETY 3) (SPEED 1) (SPACE 1)))
238 (DECLARE (TYPE (SIMPLE-ARRAY CONS 1) X))
239 (WHEN (CONSP (AREF X 0))
241 (BAR (VECTOR (MAKE-FOO :A 11 :B 12)))
244 in SBCL 0.6.5 (and also in CMU CL 18b). This does not happen for
245 all cases, e.g. the type assumption *is* checked if the array
246 elements are declared to be of some structure type instead of CONS.
249 The printer doesn't report closures very well. This is true in
253 #<Closure Over Function "DEFUN STRUCTURE-SLOT-ACCESSOR" {134D1A1}>
254 It would be nice to make closures have a settable name slot,
255 and make things like DEFSTRUCT and FLET, which create closures,
256 set helpful values into this slot.
259 And as long as we're wishing, it would be awfully nice if INSPECT could
260 also report on closures, telling about the values of the bound variables.
263 The compiler assumes that any time a function of declared FTYPE
264 doesn't signal an error, its arguments were of the declared type.
265 E.g. compiling and loading
266 (DECLAIM (OPTIMIZE (SAFETY 3)))
267 (DEFUN FACTORIAL (X) (GAMMA (1+ X)))
268 (DECLAIM (FTYPE (FUNCTION (UNSIGNED-BYTE) FACTORIAL)))
270 (COND ((> (FACTORIAL X) 1.0E6)
271 (FORMAT T "too big~%"))
273 (FORMAT T "exactly ~S~%" (FACTORIAL X)))
275 (FORMAT T "approximately ~S~%" (FACTORIAL X)))))
278 will cause the INTEGERP case to be selected, giving bogus output a la
280 This violates the "declarations are assertions" principle.
281 According to the ANSI spec, in the section "System Class FUNCTION",
282 this is a case of "lying to the compiler", but the lying is done
283 by the code which calls FACTORIAL with non-UNSIGNED-BYTE arguments,
284 not by the unexpectedly general definition of FACTORIAL. In any case,
285 "declarations are assertions" means that lying to the compiler should
286 cause an error to be signalled, and should not cause a bogus
287 result to be returned. Thus, the compiler should not assume
288 that arbitrary functions check their argument types. (It might
289 make sense to add another flag (CHECKED?) to DEFKNOWN to
290 identify functions which *do* check their argument types.)
293 DEFMETHOD doesn't check the syntax of &REST argument lists properly,
294 accepting &REST even when it's not followed by an argument name:
295 (DEFMETHOD FOO ((X T) &REST) NIL)
298 TYPEP of VALUES types is sometimes implemented very inefficiently, e.g. in
299 (DEFTYPE INDEXOID () '(INTEGER 0 1000))
301 (DECLARE (TYPE INDEXOID X))
302 (THE (VALUES INDEXOID)
304 where the implementation of the type check in function FOO
305 includes a full call to %TYPEP. There are also some fundamental problems
306 with the interpretation of VALUES types (inherited from CMU CL, and
307 from the ANSI CL standard) as discussed on the cmucl-imp@cons.org
308 mailing list, e.g. in Robert Maclachlan's post of 21 Jun 2000.
311 The definitions of SIGCONTEXT-FLOAT-REGISTER and
312 %SET-SIGCONTEXT-FLOAT-REGISTER in x86-vm.lisp say they're not
313 supported on FreeBSD because the floating point state is not saved,
314 but at least as of FreeBSD 4.0, the floating point state *is* saved,
315 so they could be supported after all. Very likely
316 SIGCONTEXT-FLOATING-POINT-MODES could now be supported, too.
319 (as discussed by Douglas Crosher on the cmucl-imp mailing list ca.
320 Aug. 10, 2000): CMUCL currently interprets 'member as '(member); same
321 issue with 'union, 'and, 'or etc. So even though according to the
322 ANSI spec, bare 'MEMBER, 'AND, and 'OR are not legal types, CMUCL
323 (and now SBCL) interpret them as legal types.
326 ANSI specifies DEFINE-SYMBOL-MACRO, but it's not defined in SBCL.
327 CMU CL added it ca. Aug 13, 2000, after some discussion on the mailing
328 list, and it is probably possible to use substantially the same
329 patches to add it to SBCL.
332 a slew of floating-point-related errors reported by Peter Van Eynde
334 a: (fixed in sbcl-0.6.11.25)
335 b: SBCL's value for LEAST-POSITIVE-SHORT-FLOAT is bogus, and
336 should probably be 1.4012985e-45. In SBCL,
337 (/ LEAST-POSITIVE-SHORT-FLOAT 2) returns a number smaller
338 than LEAST-POSITIVE-SHORT-FLOAT. Similar problems
339 exist for LEAST-NEGATIVE-SHORT-FLOAT, LEAST-POSITIVE-LONG-FLOAT,
340 and LEAST-NEGATIVE-LONG-FLOAT.
341 c: Many expressions generate floating infinity:
346 PVE's regression tests want them to raise errors. SBCL
347 generates the infinities instead, which may or may not be
349 d: (in section12.erg) various forms a la
350 (FLOAT 1 DOUBLE-FLOAT-EPSILON)
351 don't give the right behavior.
354 type safety errors reported by Peter Van Eynde July 25, 2000:
355 a: (COERCE (QUOTE (A B C)) (QUOTE (VECTOR * 4)))
357 In general lengths of array type specifications aren't
358 checked by COERCE, so it fails when the spec is
359 (VECTOR 4), (STRING 2), (SIMPLE-BIT-VECTOR 3), or whatever.
360 b: CONCATENATE has the same problem of not checking the length
361 of specified output array types. MAKE-SEQUENCE and MAP and
362 MERGE also have the same problem.
363 c: (COERCE 'AND 'FUNCTION) returns something related to
364 (MACRO-FUNCTION 'AND), but ANSI says it should raise an error.
365 d: ELT signals SIMPLE-ERROR if its index argument
366 isn't a valid index for its sequence argument, but should
367 signal TYPE-ERROR instead.
368 e: FILE-LENGTH is supposed to signal a type error when its
369 argument is not a stream associated with a file, but doesn't.
370 f: (FLOAT-RADIX 2/3) should signal an error instead of
372 g: (LOAD "*.lsp") should signal FILE-ERROR.
373 h: (MAKE-CONCATENATED-STREAM (MAKE-STRING-OUTPUT-STREAM))
374 should signal TYPE-ERROR.
375 i: MAKE-TWO-WAY-STREAM doesn't check that its arguments can
376 be used for input and output as needed. It should fail with
377 TYPE-ERROR when handed e.g. the results of
378 MAKE-STRING-INPUT-STREAM or MAKE-STRING-OUTPUT-STREAM in
379 the inappropriate positions, but doesn't.
380 j: (PARSE-NAMESTRING (COERCE (LIST #\f #\o #\o (CODE-CHAR 0) #\4 #\8)
382 should probably signal an error instead of making a pathname with
384 k: READ-BYTE is supposed to signal TYPE-ERROR when its argument is
385 not a binary input stream, but instead cheerfully reads from
386 character streams, e.g. (MAKE-STRING-INPUT-STREAM "abc").
389 DEFCLASS bugs reported by Peter Van Eynde July 25, 2000:
390 a: (DEFCLASS FOO () (A B A)) should signal a PROGRAM-ERROR, and
392 b: (DEFCLASS FOO () (A B A) (:DEFAULT-INITARGS X A X B)) should
393 signal a PROGRAM-ERROR, and doesn't.
394 c: (DEFCLASS FOO07 NIL ((A :ALLOCATION :CLASS :ALLOCATION :CLASS))),
395 and other DEFCLASS forms with duplicate specifications in their
396 slots, should signal a PROGRAM-ERROR, and doesn't.
397 d: (DEFGENERIC IF (X)) should signal a PROGRAM-ERROR, but instead
398 causes a COMPILER-ERROR.
401 SYMBOL-MACROLET bugs reported by Peter Van Eynde July 25, 2000:
402 a: (SYMBOL-MACROLET ((T TRUE)) ..) should probably signal
403 PROGRAM-ERROR, but SBCL accepts it instead.
404 b: SYMBOL-MACROLET should refuse to bind something which is
405 declared as a global variable, signalling PROGRAM-ERROR.
406 c: SYMBOL-MACROLET should signal PROGRAM-ERROR if something
407 it binds is declared SPECIAL inside.
410 LOOP bugs reported by Peter Van Eynde July 25, 2000:
411 a: (LOOP WITH (A B) DO (PRINT 1)) is a syntax error according to
412 the definition of WITH clauses given in the ANSI spec, but
413 compiles and runs happily in SBCL.
414 b: a messy one involving package iteration:
415 interpreted Form: (LET ((PACKAGE (MAKE-PACKAGE "LOOP-TEST"))) (INTERN "blah" PACKAGE) (LET ((BLAH2 (INTERN "blah2" PACKAGE))) (EXPORT BLAH2 PACKAGE)) (LIST (SORT (LOOP FOR SYM BEING EACH PRESENT-SYMBOL OF PACKAGE FOR SYM-NAME = (SYMBOL-NAME SYM) COLLECT SYM-NAME) (FUNCTION STRING<)) (SORT (LOOP FOR SYM BEING EACH EXTERNAL-SYMBOL OF PACKAGE FOR SYM-NAME = (SYMBOL-NAME SYM) COLLECT SYM-NAME) (FUNCTION STRING<))))
416 Should be: (("blah" "blah2") ("blah2"))
417 SBCL: (("blah") ("blah2"))
418 * (LET ((X 1)) (LOOP FOR I BY (INCF X) FROM X TO 10 COLLECT I))
419 doesn't work -- SBCL's LOOP says BY isn't allowed in a FOR clause.
422 type system errors reported by Peter Van Eynde July 25, 2000:
423 a: (SUBTYPEP 'BIGNUM 'INTEGER) => NIL, NIL
424 but should be (VALUES T T) instead.
425 b: (SUBTYPEP 'EXTENDED-CHAR 'CHARACTER) => NIL, NIL
426 but should be (VALUES T T) instead.
427 c: (SUBTYPEP '(INTEGER (0) (0)) 'NIL) dies with nested errors.
428 d: In general, the system doesn't like '(INTEGER (0) (0)) -- it
429 blows up at the level of SPECIFIER-TYPE with
430 "Lower bound (0) is greater than upper bound (0)." Probably
431 SPECIFIER-TYPE should return NIL instead.
432 e: (TYPEP 0 '(COMPLEX (EQL 0)) fails with
433 "Component type for Complex is not numeric: (EQL 0)."
434 This might be easy to fix; the type system already knows
435 that (SUBTYPEP '(EQL 0) 'NUMBER) is true.
436 f: The type system doesn't know about the condition system,
437 so that e.g. (TYPEP 'SIMPLE-ERROR 'ERROR)=>NIL.
438 g: The type system isn't all that smart about relationships
439 between hairy types, as shown in the type.erg test results,
440 e.g. (SUBTYPEP 'CONS '(NOT ATOM)) => NIL, NIL.
443 miscellaneous errors reported by Peter Van Eynde July 25, 2000:
445 (DEFGENERIC FOO02 (X))
446 (DEFMETHOD FOO02 ((X NUMBER)) T)
447 (LET ((M (FIND-METHOD (FUNCTION FOO02)
449 (LIST (FIND-CLASS (QUOTE NUMBER))))))
450 (REMOVE-METHOD (FUNCTION FOO02) M)
451 (DEFGENERIC FOO03 (X))
452 (ADD-METHOD (FUNCTION FOO03) M)))
453 should give an error, but SBCL allows it.
454 b: READ should probably return READER-ERROR, not the bare
455 arithmetic error, when input a la "1/0" or "1e1000" causes
459 It has been reported (e.g. by Peter Van Eynde) that there are
460 several metaobject protocol "errors". (In order to fix them, we might
461 need to document exactly what metaobject protocol specification
462 we're following -- the current code is just inherited from PCL.)
465 another error from Peter Van Eynde 5 September 2000:
466 (FORMAT NIL "~F" "FOO") should work, but instead reports an error.
467 PVE submitted a patch to deal with this bug, but it exposes other
468 comparably serious bugs, so I didn't apply it. It looks as though
469 the FORMAT code needs a fair amount of rewriting in order to comply
470 with the various details of the ANSI spec.
473 The implementation of #'+ returns its single argument without
474 type checking, e.g. (+ "illegal") => "illegal".
477 In sbcl-0.6.7, there is no doc string for CL:PUSH, probably
478 because it's defined with the DEFMACRO-MUNDANELY macro and something
479 is wrong with doc string setting in that macro.
482 Attempting to use COMPILE on something defined by DEFMACRO fails:
483 (DEFMACRO FOO (X) (CONS X X))
485 Error in function C::GET-LAMBDA-TO-COMPILE:
486 #<Closure Over Function "DEFUN (SETF MACRO-FUNCTION)" {480E21B1}> was defined in a non-null environment.
489 (SUBTYPEP '(AND ZILCH INTEGER) 'ZILCH) => NIL, NIL
490 Note: I looked into fixing this in 0.6.11.15, but gave up. The
491 problem seems to be that there are two relevant type methods for
492 the subtypep operation, HAIRY :COMPLEX-SUBTYPEP-ARG2 and
493 INTERSECTION :COMPLEX-SUBTYPEP-ARG1, and only the first is
494 called. This could be fixed, but type dispatch is messy and
495 confusing enough already, I don't want to complicate it further.
496 Perhaps someday we can make CLOS cross-compiled (instead of compiled
497 after bootstrapping) so that we don't need to have the type system
498 available before CLOS, and then we can rewrite the type methods to
499 CLOS methods, and then expressing the solutions to stuff like this
500 should become much more straightforward. -- WHN 2001-03-14
503 CL:*DEFAULT-PATHNAME-DEFAULTS* doesn't behave as ANSI suggests (reflecting
504 current working directory). And there's no supported way to update
505 or query the current working directory (a la Unix "chdir" and "pwd"),
506 which is functionality that ILISP needs (and currently gets with low-level
510 The debugger LIST-LOCATIONS command doesn't work properly.
513 Compiling and loading
514 (DEFUN FAIL (X) (THROW 'FAIL-TAG X))
516 then requesting a BACKTRACE at the debugger prompt gives no information
517 about where in the user program the problem occurred.
520 The compiler is supposed to do type inference well enough that
523 ((SIMPLE-ARRAY SINGLE-FLOAT)
525 (DECLARE (TYPE (SIMPLE-ARRAY SINGLE-FLOAT) X))
528 is redundant. However, as reported by Juan Jose Garcia Ripoll for
529 CMU CL, it sometimes doesn't. Adding declarations is a pretty good
530 workaround for the problem for now, but can't be done by the TYPECASE
531 macros themselves, since it's too hard for the macro to detect
532 assignments to the variable within the clause.
533 Note: The compiler *is* smart enough to do the type inference in
534 many cases. This case, derived from a couple of MACROEXPAND-1
535 calls on Ripoll's original test case,
537 (DECLARE (OPTIMIZE SPEED (SAFETY 0)))
538 (COND ((TYPEP A '(SIMPLE-ARRAY SINGLE-FLOAT)) NIL
539 (LET ((LENGTH (ARRAY-TOTAL-SIZE A)))
540 (LET ((I 0) (G2554 LENGTH))
541 (DECLARE (TYPE REAL G2554) (TYPE REAL I))
544 (WHEN (>= I G2554) (GO SB-LOOP::END-LOOP))
545 (SETF (ROW-MAJOR-AREF A I) (- (ROW-MAJOR-AREF A I)))
546 (GO SB-LOOP::NEXT-LOOP)
547 SB-LOOP::END-LOOP))))))
548 demonstrates the problem; but the problem goes away if the TAGBODY
549 and GO forms are removed (leaving the SETF in ordinary, non-looping
550 code), or if the TAGBODY and GO forms are retained, but the
551 assigned value becomes 0.0 instead of (- (ROW-MAJOR-AREF A I)).
554 Paul Werkowski wrote on cmucl-imp@cons.org 2000-11-15
555 I am looking into this problem that showed up on the cmucl-help
556 list. It seems to me that the "implementation specific environment
557 hacking functions" found in pcl/walker.lisp are completely messed
558 up. The good thing is that they appear to be barely used within
559 PCL and the munged environment object is passed to cmucl only
560 in calls to macroexpand-1, which is probably why this case fails.
561 SBCL uses essentially the same code, so if the environment hacking
562 is screwed up, it affects us too.
565 Using the pretty-printer from the command prompt gives funny
566 results, apparently because the pretty-printer doesn't know
567 about user's command input, including the user's carriage return
568 that the user, and therefore the pretty-printer thinks that
569 the new output block should start indented 2 or more characters
570 rightward of the correct location.
573 (probably related to bug #70)
574 As reported by Carl Witty on submit@bugs.debian.org 1999-05-08,
576 (in-package "CL-USER")
577 (defun equal-terms (termx termy)
579 ((alpha-equal-bound-term-lists (listx listy)
580 (or (and (null listx) (null listy))
582 (let ((bindings-x (bindings-of-bound-term (car listx)))
583 (bindings-y (bindings-of-bound-term (car listy))))
584 (if (and (null bindings-x) (null bindings-y))
585 (alpha-equal-terms (term-of-bound-term (car listx))
586 (term-of-bound-term (car listy)))
587 (and (= (length bindings-x) (length bindings-y))
589 (enter-binding-pairs (bindings-of-bound-term (car listx))
590 (bindings-of-bound-term (car listy)))
591 (alpha-equal-terms (term-of-bound-term (car listx))
592 (term-of-bound-term (car listy)))
593 (exit-binding-pairs (bindings-of-bound-term (car listx))
594 (bindings-of-bound-term (car listy)))))))
595 (alpha-equal-bound-term-lists (cdr listx) (cdr listy)))))
597 (alpha-equal-terms (termx termy)
598 (if (and (variable-p termx)
600 (equal-bindings (id-of-variable-term termx)
601 (id-of-variable-term termy))
602 (and (equal-operators-p (operator-of-term termx) (operator-of-term termy))
603 (alpha-equal-bound-term-lists (bound-terms-of-term termx)
604 (bound-terms-of-term termy))))))
608 (with-variable-invocation (alpha-equal-terms termx termy))))))
609 causes an assertion failure
610 The assertion (EQ (C::LAMBDA-TAIL-SET C::CALLER)
611 (C::LAMBDA-TAIL-SET (C::LAMBDA-HOME C::CALLEE))) failed.
613 Bob Rogers reports (1999-07-28 on cmucl-imp@cons.org) a smaller test
614 case with the same problem:
615 (defun parse-fssp-alignment ()
616 ;; Given an FSSP alignment file named by the argument . . .
617 (labels ((get-fssp-char ()
621 ;; Stub body, enough to tickle the bug.
622 (list (read-fssp-char)
626 ANSI specifies that the RESULT-TYPE argument of CONCATENATE must be
627 a subtype of SEQUENCE, but CONCATENATE doesn't check this properly:
628 (CONCATENATE 'SIMPLE-ARRAY #(1 2) '(3)) => #(1 2 3)
629 This also leads to funny behavior when derived type specifiers
630 are used, as originally reported by Milan Zamazal for CMU CL (on the
631 Debian bugs mailing list (?) 2000-02-27), then reported by Martin
632 Atzmueller for SBCL (2000-10-01 on sbcl-devel@lists.sourceforge.net):
633 (DEFTYPE FOO () 'SIMPLE-ARRAY)
634 (CONCATENATE 'FOO #(1 2) '(3))
635 => #<ARRAY-TYPE SIMPLE-ARRAY> is a bad type specifier for
637 The derived type specifier FOO should act the same way as the
638 built-in type SIMPLE-ARRAY here, but it doesn't. That problem
639 doesn't seem to exist for sequence types:
640 (DEFTYPE BAR () 'SIMPLE-VECTOR)
641 (CONCATENATE 'BAR #(1 2) '(3)) => #(1 2 3)
644 As reported by Winton Davies on a CMU CL mailing list 2000-01-10,
645 and reported for SBCL by Martin Atzmueller 2000-10-20: (TRACE GETHASH)
646 crashes SBCL. In general tracing anything which is used in the
647 implementation of TRACE is likely to have the same problem.
650 As reported by Daniel Solaz on cmucl-help@cons.org 2000-11-23,
651 SXHASH returns the same value for all non-STRUCTURE-OBJECT instances,
652 notably including all PCL instances. There's a limit to how much
653 SXHASH can do to return unique values for instances, but at least
654 it should probably look at the class name, the way that it does
655 for STRUCTURE-OBJECTs.
658 As reported by Martin Atzmueller on the sbcl-devel list 2000-11-22,
659 > There remains one issue, that is a bug in SBCL:
660 > According to my interpretation of the spec, the ":" and "@" modifiers
661 > should appear _after_ the comma-seperated arguments.
662 > Well, SBCL (and CMUCL for that matter) accept
663 > (ASSERT (STRING= (FORMAT NIL "~:8D" 1) " 1"))
664 > where the correct way (IMHO) should be
665 > (ASSERT (STRING= (FORMAT NIL "~8:D" 1) " 1"))
666 Probably SBCL should stop accepting the "~:8D"-style format arguments,
667 or at least issue a warning.
670 (probably related to bug #65)
671 The compiler doesn't like &OPTIONAL arguments in LABELS and FLET
673 (DEFUN FIND-BEFORE (ITEM SEQUENCE &KEY (TEST #'EQL))
674 (LABELS ((FIND-ITEM (OBJ SEQ TEST &OPTIONAL (VAL NIL))
675 (LET ((ITEM (FIRST SEQ)))
678 ((FUNCALL TEST OBJ ITEM)
681 (FIND-ITEM OBJ (REST SEQ) TEST (NCONC VAL `(,ITEM))))))))
682 (FIND-ITEM ITEM SEQUENCE TEST)))
683 from David Young's bug report on cmucl-help@cons.org 30 Nov 2000
684 causes sbcl-0.6.9 to fail with
685 error in function SB-KERNEL:ASSERT-ERROR:
686 The assertion (EQ (SB-C::LAMBDA-TAIL-SET SB-C::CALLER)
687 (SB-C::LAMBDA-TAIL-SET
688 (SB-C::LAMBDA-HOME SB-C::CALLEE))) failed.
691 (DECLAIM (OPTIMIZE ..)) doesn't work. E.g. even after
692 (DECLAIM (OPTIMIZE (SPEED 3))), things are still optimized with
693 the previous SPEED policy. This bug will probably get fixed in
694 0.6.9.x in a general cleanup of optimization policy.
697 (DECLAIM (OPTIMIZE ..)) doesn't work properly inside LOCALLY forms.
700 As noted in the ANSI specification for COERCE, (COERCE 3 'COMPLEX)
701 gives a result which isn't COMPLEX. The result type optimizer
702 for COERCE doesn't know this, perhaps because it was written before
703 ANSI threw this curveball: the optimizer thinks that COERCE always
704 returns a result of the specified type. Thus while the interpreted
706 (DEFUN TRICKY (X) (TYPEP (COERCE X 'COMPLEX) 'COMPLEX))
707 returns the correct result,
709 the compiled function
715 As reported by Martin Atzmueller on sbcl-devel 26 Dec 2000,
716 ANSI says that WITH-OUTPUT-TO-STRING should have a keyword
717 :ELEMENT-TYPE, but in sbcl-0.6.9 this is not defined for
718 WITH-OUTPUT-TO-STRING.
721 ANSI says in one place that type declarations can be abbreviated even
722 when the type name is not a symbol, e.g.
723 (DECLAIM ((VECTOR T) *FOOVECTOR*))
724 SBCL doesn't support this. But ANSI says in another place that this
725 isn't allowed. So it's not clear this is a bug after all. (See the
726 e-mail on cmucl-help@cons.org on 2001-01-16 and 2001-01-17 from WHN
730 as pointed out by Dan Barlow on sbcl-devel 2000-07-02:
731 The PICK-TEMPORARY-FILE-NAME utility used by LOAD-FOREIGN uses
732 an easily guessable temporary filename in a way which might open
733 applications using LOAD-FOREIGN to hijacking by malicious users
734 on the same machine. Incantations for doing this safely are
735 floating around the net in various "how to write secure programs
736 despite Unix" documents, and it would be good to (1) fix this in
737 LOAD-FOREIGN, and (2) hunt for any other code which uses temporary
738 files and make it share the same new safe logic.
741 (fixed early Feb 2001 by MNA)
744 As reported by wbuss@TELDA.NET (Wolfhard Buss) on cmucl-help
747 (loop with (a . b) of-type float = '(0.0 . 1.0)
748 and (c . d) of-type float = '(2.0 . 3.0)
749 return (list a b c d))
750 should evaluate to (0.0 1.0 2.0 3.0). cmucl-18c disagrees and
751 invokes the debugger: "B is not of type list".
752 SBCL does the same thing.
755 Functions are assigned names based on the context in which they're
756 defined. This is less than ideal for the functions which are
757 used to implement CLOS methods. E.g. the output of
758 (DESCRIBE 'PRINT-OBJECT) lists functions like
759 #<FUNCTION "DEF!STRUCT (TRACE-INFO (:MAKE-LOAD-FORM-FUN SB-KERNEL:JUST-DUMP-IT-NORMALLY) (:PRINT-OBJECT #))" {1020E49}>
761 #<FUNCTION "MACROLET ((FORCE-DELAYED-DEF!METHODS NIL #))" {1242871}>
762 It would be better if these functions' names always identified
763 them as methods, and identified their generic functions and
767 RANDOM-INTEGER-EXTRA-BITS=10 may not be large enough for the RANDOM
768 RNG to be high quality near RANDOM-FIXNUM-MAX; it looks as though
769 the mean of the distribution can be systematically O(0.1%) wrong.
770 Just increasing R-I-E-B is probably not a good solution, since
771 it would decrease efficiency more than is probably necessary. Perhaps
772 using some sort of accept/reject method would be better.
775 (SUBTYPEP '(SATISFIES SOME-UNDEFINED-FUN) NIL)=>NIL,T (should be NIL,NIL)
778 Internally the compiler sometimes evaluates
779 (sb-kernel:type/= (specifier-type '*) (specifier-type t))
780 (I stumbled across this when I added an
781 (assert (not (eq type1 *wild-type*)))
782 in the NAMED :SIMPLE-= type method.) '* isn't really a type, and
783 in a type context should probably be translated to T, and so it's
784 probably to ask whether it's equal to the T type and then (using the
785 EQ type comparison in the NAMED :SIMPLE-= type method) return NIL.
786 (I haven't tried to investigate this bug enough to guess whether
787 there might be any user-level symptoms.)
790 a latent cross-compilation/bootstrapping bug: The cross-compilation
791 host's CL:CHAR-CODE-LIMIT is used in target code in readtable.lisp
792 and possibly elsewhere. Instead, we should use the target system's
793 CHAR-CODE-LIMIT. This will probably cause problems if we try to
794 bootstrap on a system which uses a different value of CHAR-CODE-LIMIT
798 (subtypep '(or (integer -1 1)
802 (integer -1 1))) => NIL,T
803 An analogous problem with SINGLE-FLOAT and REAL types was fixed in
804 sbcl-0.6.11.22, but some peculiarites of the RATIO type make it
805 awkward to generalize the fix to INTEGER and RATIONAL. It's not
806 clear what's the best fix. (See the "bug in type handling" discussion
807 on cmucl-imp ca. 2001-03-22 and ca. 2001-02-12.)
810 In sbcl-0.6.11.26, (COMPILE 'IN-HOST-COMPILATION-MODE) in
811 src/cold/shared.lisp doesn't correctly translate the
813 (defun in-host-compilation-mode (fn)
814 (let ((*features* (cons :sb-xc-host *features*))
815 ;; the CROSS-FLOAT-INFINITY-KLUDGE, as documented in
816 ;; base-target-features.lisp-expr:
817 (*shebang-features* (set-difference *shebang-features*
818 '(:sb-propagate-float-type
819 :sb-propagate-fun-type))))
820 (with-additional-nickname ("SB-XC" "SB!XC")
822 No error is reported by the compiler, but when the function is executed,
824 TYPE-ERROR in SB-KERNEL::OBJECT-NOT-TYPE-ERROR-HANDLER:
825 (:LINUX :X86 :IEEE-FLOATING-POINT :SB-CONSTRAIN-FLOAT-TYPE :SB-TEST
826 :SB-INTERPRETER :SB-DOC :UNIX ...) is not of type SYMBOL.
829 Inconsistencies between derived and declared VALUES return types for
830 DEFUN aren't checked very well. E.g. the logic which successfully
831 catches problems like
832 (declaim (ftype (function (fixnum) float) foo))
834 (declare (type integer x))
835 (values x)) ; wrong return type, detected, gives warning, good!
837 (declaim (ftype (function (t) (values t t)) bar))
839 (values x)) ; wrong number of return values, no warning, bad!
840 The cause of this is seems to be that (1) the internal function
841 VALUES-TYPES-EQUAL-OR-INTERSECT used to make the check handles its
842 arguments symmetrically, and (2) when the type checking code was
843 written back when when SBCL's code was still CMU CL, the intent
845 (declaim (ftype (function (t) t) bar))
847 (values x x)) ; wrong number of return values; should give warning?
848 not be warned for, because a two-valued return value is considered
849 to be compatible with callers who expects a single value to be
850 returned. That intent is probably not appropriate for modern ANSI
851 Common Lisp, but fixing this might be complicated because of other
852 divergences between auld-style and new-style handling of
853 multiple-VALUES types. (Some issues related to this were discussed
854 on cmucl-imp at some length sometime in 2000.)
857 The facility for dumping a running Lisp image to disk gets confused
858 when run without the PURIFY option, and creates an unnecessarily large
859 core file (apparently representing memory usage up to the previous
860 high-water mark). Moreover, when the file is loaded, it confuses the
861 GC, so that thereafter memory usage can never be reduced below that
865 The TRACE facility can't be used on some kinds of functions.
866 (Basically, the breakpoint facility was incompletely implemented
867 in the X86 port of CMU CL, and hasn't been fixed in SBCL.)
870 In sbcl-0.6.11.41 (and in all earlier SBCL, and in CMU
871 CL), out-of-line structure slot setters are horribly inefficient
872 whenever the type of the slot is declared, because out-of-line
873 structure slot setters are implemented as closures to save space,
874 so the compiler doesn't compile the type test into code, but
875 instead just saves the type in a lexical closure and interprets it
877 A proper solution involves deciding whether it's really worth
878 saving space by implementing structure slot accessors as closures.
879 (If it's not worth it, the problem vanishes automatically. If it
880 is worth it, there are hacks we could use to force type tests to
881 be compiled anyway, and even shared. E.g. we could implement
882 an EQUAL hash table mapping from types to compiled type tests,
883 and save the appropriate compiled type test as part of each lexical
884 closure; or we could make the lexical closures be placeholders
885 which overwrite their old definition as a lexical closure with
886 a new compiled definition the first time that they're called.)
887 As a workaround for the problem, #'(SETF FOO) expressions can
888 be replaced with (EFFICIENT-SETF-FUNCTION FOO), where
889 (defmacro efficient-setf-function (place-function-name)
890 (or #+sbcl (and (sb-impl::info :function :accessor-for place-function-name)
891 ;; a workaround for the problem, encouraging the
892 ;; inline expansion of the structure accessor, so
893 ;; that the compiler can optimize its type test
894 (let ((new-value (gensym "NEW-VALUE-"))
895 (structure-value (gensym "STRUCTURE-VALUE-")))
896 `(lambda (,new-value ,structure-value)
897 (setf (,place-function-name ,structure-value)
899 ;; no problem, can just use the ordinary expansion
900 `(function (setf ,place-function-name))))
903 DESCRIBE interacts poorly with *PRINT-CIRCLE*, e.g. the output from
904 (let ((*print-circle* t)) (describe (make-hash-table)))
906 #<HASH-TABLE :TEST EQL :COUNT 0 {90BBFC5}> is an . (EQL)
908 Its REHASH-SIZE is 1.5. Its REHASH-THRESHOLD is . (1.0)
909 It holds 0 key/value pairs.
910 where the ". (EQL)" and ". (1.0)" substrings are screwups.
911 (This is likely a pretty-printer problem which happens to
912 be exercised by DESCRIBE, not actually a DESCRIBE problem.)
915 There's apparently a bug in CEILING optimization which caused
916 Douglas Crosher to patch the CMU CL version. Martin Atzmueller
917 applied the patches to SBCL and they didn't seem to cause problems
918 (as reported sbcl-devel 2001-05-04). However, since the patches
919 modify nontrivial code which was apparently written incorrectly
920 the first time around, until regression tests are written I'm not
921 comfortable merging the patches in the CVS version of SBCL.
924 KNOWN BUGS RELATED TO THE IR1 INTERPRETER
926 (Note: At some point, the pure interpreter (actually a semi-pure
927 interpreter aka "the IR1 interpreter") will probably go away, replaced
929 (DEFUN EVAL (X) (FUNCALL (COMPILE NIL (LAMBDA ..)))))
930 and at that time these bugs should either go away automatically or
931 become more tractable to fix. Until then, they'll probably remain,
932 since some of them aren't considered urgent, and the rest are too hard
933 to fix as long as so many special cases remain. After the IR1
934 interpreter goes away is also the preferred time to start
935 systematically exterminating cases where debugging functionality
936 (backtrace, breakpoint, etc.) breaks down, since getting rid of the
937 IR1 interpreter will reduce the number of special cases we need to
941 The FUNCTION special operator doesn't check properly whether its
942 argument is a function name. E.g. (FUNCTION (X Y)) returns a value
943 instead of failing with an error. (Later attempting to funcall the
944 value does cause an error.)
947 COMPILED-FUNCTION-P bogusly reports T for interpreted functions:
948 * (DEFUN FOO (X) (- 12 X))
950 * (COMPILED-FUNCTION-P #'FOO)
955 (DEFVAR *SUPPRESS-P* T)
956 (EVAL '(UNLESS *SUPPRESS-P*
957 (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
958 (FORMAT T "surprise!"))))
959 prints "surprise!". Probably the entire EVAL-WHEN mechanism ought to be
960 rewritten from scratch to conform to the ANSI definition, abandoning
961 the *ALREADY-EVALED-THIS* hack which is used in sbcl-0.6.8.9 (and
962 in the original CMU CL source, too). This should be easier to do --
963 though still nontrivial -- once the various IR1 interpreter special
967 EVAL-WHEN's idea of what's a toplevel form is even more screwed up
968 than the example in IR1-3 would suggest, since COMPILE-FILE and
969 COMPILE both print both "right now!" messages when compiling the
973 (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
974 (PRINT "yes! right now!"))
977 (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
978 (PRINT "no! right now!"))
980 and while EVAL doesn't print the "right now!" messages, the first
981 FUNCALL on the value returned by EVAL causes both of them to be printed.
984 The system accepts DECLAIM in most places where DECLARE would be
985 accepted, without even issuing a warning. ANSI allows this, but since
986 it's fairly easy to mistype DECLAIM instead of DECLARE, and the
987 meaning is rather different, and it's unlikely that the user
988 has a good reason for doing DECLAIM not at top level, it would be
989 good to issue a STYLE-WARNING when this happens. A possible
990 fix would be to issue STYLE-WARNINGs for DECLAIMs not at top level,
991 or perhaps to issue STYLE-WARNINGs for any EVAL-WHEN not at top level.
992 [This is considered an IR1-interpreter-related bug because until
993 EVAL-WHEN is rewritten, which won't happen until after the IR1
994 interpreter is gone, the system's notion of what's a top-level form
995 and what's not will remain too confused to fix this problem.]