+
+61:
+ Compiling and loading
+ (DEFUN FAIL (X) (THROW 'FAIL-TAG X))
+ (FAIL 12)
+ then requesting a BACKTRACE at the debugger prompt gives no information
+ about where in the user program the problem occurred.
+
+62:
+ The compiler is supposed to do type inference well enough that
+ the declaration in
+ (TYPECASE X
+ ((SIMPLE-ARRAY SINGLE-FLOAT)
+ (LOCALLY
+ (DECLARE (TYPE (SIMPLE-ARRAY SINGLE-FLOAT) X))
+ ..))
+ ..)
+ is redundant. However, as reported by Juan Jose Garcia Ripoll for
+ CMU CL, it sometimes doesn't. Adding declarations is a pretty good
+ workaround for the problem for now, but can't be done by the TYPECASE
+ macros themselves, since it's too hard for the macro to detect
+ assignments to the variable within the clause.
+ Note: The compiler *is* smart enough to do the type inference in
+ many cases. This case, derived from a couple of MACROEXPAND-1
+ calls on Ripoll's original test case,
+ (DEFUN NEGMAT (A)
+ (DECLARE (OPTIMIZE SPEED (SAFETY 0)))
+ (COND ((TYPEP A '(SIMPLE-ARRAY SINGLE-FLOAT)) NIL
+ (LET ((LENGTH (ARRAY-TOTAL-SIZE A)))
+ (LET ((I 0) (G2554 LENGTH))
+ (DECLARE (TYPE REAL G2554) (TYPE REAL I))
+ (TAGBODY
+ SB-LOOP::NEXT-LOOP
+ (WHEN (>= I G2554) (GO SB-LOOP::END-LOOP))
+ (SETF (ROW-MAJOR-AREF A I) (- (ROW-MAJOR-AREF A I)))
+ (GO SB-LOOP::NEXT-LOOP)
+ SB-LOOP::END-LOOP))))))
+ demonstrates the problem; but the problem goes away if the TAGBODY
+ and GO forms are removed (leaving the SETF in ordinary, non-looping
+ code), or if the TAGBODY and GO forms are retained, but the
+ assigned value becomes 0.0 instead of (- (ROW-MAJOR-AREF A I)).
+
+63:
+ Paul Werkowski wrote on cmucl-imp@cons.org 2000-11-15
+ I am looking into this problem that showed up on the cmucl-help
+ list. It seems to me that the "implementation specific environment
+ hacking functions" found in pcl/walker.lisp are completely messed
+ up. The good thing is that they appear to be barely used within
+ PCL and the munged environment object is passed to cmucl only
+ in calls to macroexpand-1, which is probably why this case fails.
+ SBCL uses essentially the same code, so if the environment hacking
+ is screwed up, it affects us too.
+
+64:
+ Using the pretty-printer from the command prompt gives funny
+ results, apparently because the pretty-printer doesn't know
+ about user's command input, including the user's carriage return
+ that the user, and therefore the pretty-printer thinks that
+ the new output block should start indented 2 or more characters
+ rightward of the correct location.
+
+66:
+ ANSI specifies that the RESULT-TYPE argument of CONCATENATE must be
+ a subtype of SEQUENCE, but CONCATENATE doesn't check this properly:
+ (CONCATENATE 'SIMPLE-ARRAY #(1 2) '(3)) => #(1 2 3)
+ This also leads to funny behavior when derived type specifiers
+ are used, as originally reported by Milan Zamazal for CMU CL (on the
+ Debian bugs mailing list (?) 2000-02-27), then reported by Martin
+ Atzmueller for SBCL (2000-10-01 on sbcl-devel@lists.sourceforge.net):
+ (DEFTYPE FOO () 'SIMPLE-ARRAY)
+ (CONCATENATE 'FOO #(1 2) '(3))
+ => #<ARRAY-TYPE SIMPLE-ARRAY> is a bad type specifier for
+ sequence functions.
+ The derived type specifier FOO should act the same way as the
+ built-in type SIMPLE-ARRAY here, but it doesn't. That problem
+ doesn't seem to exist for sequence types:
+ (DEFTYPE BAR () 'SIMPLE-VECTOR)
+ (CONCATENATE 'BAR #(1 2) '(3)) => #(1 2 3)
+ See also bug #46a./b., and discussion and patch sbcl-devel and
+ cmucl-imp 2002-07
+
+67:
+ As reported by Winton Davies on a CMU CL mailing list 2000-01-10,
+ and reported for SBCL by Martin Atzmueller 2000-10-20: (TRACE GETHASH)
+ crashes SBCL. In general tracing anything which is used in the
+ implementation of TRACE is likely to have the same problem.
+
+72:
+ (DECLAIM (OPTIMIZE ..)) doesn't work properly inside LOCALLY forms.
+
+75:
+ As reported by Martin Atzmueller on sbcl-devel 26 Dec 2000,
+ ANSI says that WITH-OUTPUT-TO-STRING should have a keyword
+ :ELEMENT-TYPE, but in sbcl-0.6.9 this is not defined for
+ WITH-OUTPUT-TO-STRING.
+
+78:
+ ANSI says in one place that type declarations can be abbreviated even
+ when the type name is not a symbol, e.g.
+ (DECLAIM ((VECTOR T) *FOOVECTOR*))
+ SBCL doesn't support this. But ANSI says in another place that this
+ isn't allowed. So it's not clear this is a bug after all. (See the
+ e-mail on cmucl-help@cons.org on 2001-01-16 and 2001-01-17 from WHN
+ and Pierre Mai.)
+
+79:
+ as pointed out by Dan Barlow on sbcl-devel 2000-07-02:
+ The PICK-TEMPORARY-FILE-NAME utility used by LOAD-FOREIGN uses
+ an easily guessable temporary filename in a way which might open
+ applications using LOAD-FOREIGN to hijacking by malicious users
+ on the same machine. Incantations for doing this safely are
+ floating around the net in various "how to write secure programs
+ despite Unix" documents, and it would be good to (1) fix this in
+ LOAD-FOREIGN, and (2) hunt for any other code which uses temporary
+ files and make it share the same new safe logic.
+
+82:
+ Functions are assigned names based on the context in which they're
+ defined. This is less than ideal for the functions which are
+ used to implement CLOS methods. E.g. the output of
+ (DESCRIBE 'PRINT-OBJECT) lists functions like
+ #<FUNCTION "DEF!STRUCT (TRACE-INFO (:MAKE-LOAD-FORM-FUN SB-KERNEL:JUST-DUMP-IT-NORMALLY) (:PRINT-OBJECT #))" {1020E49}>
+ and
+ #<FUNCTION "MACROLET ((FORCE-DELAYED-DEF!METHODS NIL #))" {1242871}>
+ It would be better if these functions' names always identified
+ them as methods, and identified their generic functions and
+ specializers.
+
+83:
+ RANDOM-INTEGER-EXTRA-BITS=10 may not be large enough for the RANDOM
+ RNG to be high quality near RANDOM-FIXNUM-MAX; it looks as though
+ the mean of the distribution can be systematically O(0.1%) wrong.
+ Just increasing R-I-E-B is probably not a good solution, since
+ it would decrease efficiency more than is probably necessary. Perhaps
+ using some sort of accept/reject method would be better.
+
+85:
+ Internally the compiler sometimes evaluates
+ (sb-kernel:type/= (specifier-type '*) (specifier-type t))
+ (I stumbled across this when I added an
+ (assert (not (eq type1 *wild-type*)))
+ in the NAMED :SIMPLE-= type method.) '* isn't really a type, and
+ in a type context should probably be translated to T, and so it's
+ probably wrong to ask whether it's equal to the T type and then (using
+ the EQ type comparison in the NAMED :SIMPLE-= type method) return NIL.
+ (I haven't tried to investigate this bug enough to guess whether
+ there might be any user-level symptoms.)
+
+94a:
+ Inconsistencies between derived and declared VALUES return types for
+ DEFUN aren't checked very well. E.g. the logic which successfully
+ catches problems like
+ (declaim (ftype (function (fixnum) float) foo))
+ (defun foo (x)
+ (declare (type integer x))
+ (values x)) ; wrong return type, detected, gives warning, good!
+ fails to catch
+ (declaim (ftype (function (t) (values t t)) bar))
+ (defun bar (x)
+ (values x)) ; wrong number of return values, no warning, bad!
+ The cause of this is seems to be that (1) the internal function
+ VALUES-TYPES-EQUAL-OR-INTERSECT used to make the check handles its
+ arguments symmetrically, and (2) when the type checking code was
+ written back when when SBCL's code was still CMU CL, the intent
+ was that this case
+ (declaim (ftype (function (t) t) bar))
+ (defun bar (x)
+ (values x x)) ; wrong number of return values; should give warning?
+ not be warned for, because a two-valued return value is considered
+ to be compatible with callers who expects a single value to be
+ returned. That intent is probably not appropriate for modern ANSI
+ Common Lisp, but fixing this might be complicated because of other
+ divergences between auld-style and new-style handling of
+ multiple-VALUES types. (Some issues related to this were discussed
+ on cmucl-imp at some length sometime in 2000.)
+
+95:
+ The facility for dumping a running Lisp image to disk gets confused
+ when run without the PURIFY option, and creates an unnecessarily large
+ core file (apparently representing memory usage up to the previous
+ high-water mark). Moreover, when the file is loaded, it confuses the
+ GC, so that thereafter memory usage can never be reduced below that
+ level.
+
+98:
+ In sbcl-0.6.11.41 (and in all earlier SBCL, and in CMU
+ CL), out-of-line structure slot setters are horribly inefficient
+ whenever the type of the slot is declared, because out-of-line
+ structure slot setters are implemented as closures to save space,
+ so the compiler doesn't compile the type test into code, but
+ instead just saves the type in a lexical closure and interprets it
+ at runtime.
+ A proper solution involves deciding whether it's really worth
+ saving space by implementing structure slot accessors as closures.
+ (If it's not worth it, the problem vanishes automatically. If it
+ is worth it, there are hacks we could use to force type tests to
+ be compiled anyway, and even shared. E.g. we could implement
+ an EQUAL hash table mapping from types to compiled type tests,
+ and save the appropriate compiled type test as part of each lexical
+ closure; or we could make the lexical closures be placeholders
+ which overwrite their old definition as a lexical closure with
+ a new compiled definition the first time that they're called.)
+ As a workaround for the problem, #'(SETF FOO) expressions can
+ be replaced with (EFFICIENT-SETF-FUNCTION FOO), where
+(defmacro efficient-setf-function (place-function-name)
+ (or #+sbcl (and (sb-impl::info :function :accessor-for place-function-name)
+ ;; a workaround for the problem, encouraging the
+ ;; inline expansion of the structure accessor, so
+ ;; that the compiler can optimize its type test
+ (let ((new-value (gensym "NEW-VALUE-"))
+ (structure-value (gensym "STRUCTURE-VALUE-")))
+ `(lambda (,new-value ,structure-value)
+ (setf (,place-function-name ,structure-value)
+ ,new-value))))
+ ;; no problem, can just use the ordinary expansion
+ `(function (setf ,place-function-name))))
+
+100:
+ There's apparently a bug in CEILING optimization which caused
+ Douglas Crosher to patch the CMU CL version. Martin Atzmueller
+ applied the patches to SBCL and they didn't seem to cause problems
+ (as reported sbcl-devel 2001-05-04). However, since the patches
+ modify nontrivial code which was apparently written incorrectly
+ the first time around, until regression tests are written I'm not
+ comfortable merging the patches in the CVS version of SBCL.
+
+104:
+ (DESCRIBE 'SB-ALIEN:DEF-ALIEN-TYPE) reports the macro argument list
+ incorrectly:
+ DEF-ALIEN-TYPE is
+ an external symbol
+ in #<PACKAGE "SB-ALIEN">.
+ Macro-function: #<FUNCTION "DEF!MACRO DEF-ALIEN-TYPE" {19F4A39}>
+ Macro arguments: (#:whole-470 #:environment-471)
+ On Sat, May 26, 2001 09:45:57 AM CDT it was compiled from:
+ /usr/stuff/sbcl/src/code/host-alieneval.lisp
+ Created: Monday, March 12, 2001 07:47:43 AM CST
+
+108:
+ (TIME (ROOM T)) reports more than 200 Mbytes consed even for
+ a clean, just-started SBCL system. And it seems to be right:
+ (ROOM T) can bring a small computer to its knees for a *long*
+ time trying to GC afterwards. Surely there's some more economical
+ way to implement (ROOM T).
+
+110:
+ reported by Martin Atzmueller 2001-06-25; originally from CMU CL bugs
+ collection:
+ ;;; The compiler is flushing the argument type test, and the default
+ ;;; case in the cond, so that calling with say a fixnum 0 causes a
+ ;;; SIGBUS.
+ (declaim (optimize (safety 2) (speed 3)))
+ (defun tst (x)
+ (declare (type (or string stream) x))
+ (cond ((typep x 'string) 'string)
+ ((typep x 'stream) 'stream)
+ (t
+ 'none)))
+ The symptom in sbcl-0.6.12.42 on OpenBSD is actually (TST 0)=>STREAM
+ (not the SIGBUS reported in the comment) but that's broken too;
+ type declarations are supposed to be treated as assertions unless
+ SAFETY 0, so we should be getting a TYPE-ERROR.
+
+113:
+ reported by Martin Atzmueller 2001-06-25; originally from CMU CL bugs
+ collection:
+ (in-package :cl-user)
+ ;;; From: David Gadbois <gadbois@cyc.com>
+ ;;;
+ ;;; Logical pathnames aren't externalizable.
+ ;;; Test case:
+ (let ((tempfile "/tmp/test.lisp"))
+ (setf (logical-pathname-translations "XXX")
+ '(("XXX:**;*.*" "/tmp/**/*.*")))
+ (with-open-file (out tempfile :direction :output)
+ (write-string "(defvar *path* #P\"XXX:XXX;FOO.LISP\")" out))
+ (compile-file tempfile))
+ The error message in sbcl-0.6.12.42 is
+ ; caught ERROR:
+ ; (while making load form for #<SB-IMPL::LOGICAL-HOST "XXX">)
+ ; A logical host can't be dumped as a constant: #<SB-IMPL::LOGICAL-HOST "XXX">
+
+115:
+ reported by Martin Atzmueller 2001-06-25; originally from CMU CL bugs
+ collection:
+ (in-package :cl-user)
+ ;;; The following invokes a compiler error.
+ (declaim (optimize (speed 2) (debug 3)))
+ (defun tst ()
+ (flet ((m1 ()
+ (unwind-protect nil)))
+ (if (catch nil)
+ (m1)
+ (m1))))
+ The error message in sbcl-0.6.12.42 is
+ internal error, failed AVER:
+ "(COMMON-LISP:EQ (SB!C::TN-ENVIRONMENT SB!C:TN) SB!C::TN-ENV)"
+
+117:
+ When the compiler inline expands functions, it may be that different
+ kinds of return values are generated from different code branches.
+ E.g. an inline expansion of POSITION generates integer results
+ from one branch, and NIL results from another. When that inline
+ expansion is used in a context where only one of those results
+ is acceptable, e.g.
+ (defun foo (x)
+ (aref *a1* (position x *a2*)))
+ and the compiler can't prove that the unacceptable branch is
+ never taken, then bogus type mismatch warnings can be generated.
+ If you need to suppress the type mismatch warnings, you can
+ suppress the inline expansion,
+ (defun foo (x)
+ #+sbcl (declare (notinline position)) ; to suppress bug 117 bogowarnings
+ (aref *a1* (position x *a2*)))
+ or, sometimes, suppress them by declaring the result to be of an
+ appropriate type,
+ (defun foo (x)
+ (aref *a1* (the integer (position x *a2*))))
+
+ This is not a new compiler problem in 0.7.0, but the new compiler
+ transforms for FIND, POSITION, FIND-IF, and POSITION-IF make it
+ more conspicuous. If you don't need performance from these functions,
+ and the bogus warnings are a nuisance for you, you can return to
+ your pre-0.7.0 state of grace with
+ #+sbcl (declaim (notinline find position find-if position-if)) ; bug 117..
+
+118:
+ as reported by Eric Marsden on cmucl-imp@cons.org 2001-08-14:
+ (= (FLOAT 1 DOUBLE-FLOAT-EPSILON)
+ (+ (FLOAT 1 DOUBLE-FLOAT-EPSILON) DOUBLE-FLOAT-EPSILON)) => T
+ when of course it should be NIL. (He says it only fails for X86,
+ not SPARC; dunno about Alpha.)
+
+ Also, "the same problem exists for LONG-FLOAT-EPSILON,
+ DOUBLE-FLOAT-NEGATIVE-EPSILON, LONG-FLOAT-NEGATIVE-EPSILON (though
+ for the -negative- the + is replaced by a - in the test)."
+
+ Raymond Toy comments that this is tricky on the X86 since its FPU
+ uses 80-bit precision internally.
+
+120b:
+ Even in sbcl-0.pre7.x, which is supposed to be free of the old
+ non-ANSI behavior of treating the function return type inferred
+ from the current function definition as a declaration of the
+ return type from any function of that name, the return type of NIL
+ is attached to FOO in 120a above, and used to optimize code which
+ calls FOO.
+
+122:
+ There was some sort of screwup in handling of
+ (IF (NOT (IGNORE-ERRORS ..))). E.g.
+ (defun foo1i ()
+ (if (not (ignore-errors
+ (make-pathname :host "foo" :directory "!bla" :name "bar")))
+ (print "ok")
+ (error "notunlessnot")))
+ The (NOT (IGNORE-ERRORS ..)) form evaluates to T, so this should be
+ printing "ok", but instead it's going to the ERROR. This problem
+ seems to've been introduced by MNA's HANDLER-CASE patch (sbcl-devel
+ 2001-07-17) and as a workaround (put in sbcl-0.pre7.14.flaky4.12)
+ I reverted back to the old weird HANDLER-CASE code. However, I
+ think the problem looks like a compiler bug in handling RETURN-FROM,
+ so I left the MNA-patched code in HANDLER-CASE (suppressed with
+ #+NIL) and I'd like to go back to see whether this really is
+ a compiler bug before I delete this BUGS entry.
+
+124:
+ As of version 0.pre7.14, SBCL's implementation of MACROLET makes
+ the entire lexical environment at the point of MACROLET available
+ in the bodies of the macroexpander functions. In particular, it
+ allows the function bodies (which run at compile time) to try to
+ access lexical variables (which are only defined at runtime).
+ It doesn't even issue a warning, which is bad.
+
+ The SBCL behavior arguably conforms to the ANSI spec (since the
+ spec says that the behavior is undefined, ergo anything conforms).
+ However, it would be better to issue a compile-time error.
+ Unfortunately I (WHN) don't see any simple way to detect this
+ condition in order to issue such an error, so for the meantime
+ SBCL just does this weird broken "conforming" thing.
+
+ The ANSI standard says, in the definition of the special operator
+ MACROLET,
+ The macro-expansion functions defined by MACROLET are defined
+ in the lexical environment in which the MACROLET form appears.
+ Declarations and MACROLET and SYMBOL-MACROLET definitions affect
+ the local macro definitions in a MACROLET, but the consequences
+ are undefined if the local macro definitions reference any
+ local variable or function bindings that are visible in that
+ lexical environment.
+ Then it seems to contradict itself by giving the example
+ (defun foo (x flag)
+ (macrolet ((fudge (z)
+ ;The parameters x and flag are not accessible
+ ; at this point; a reference to flag would be to
+ ; the global variable of that name.
+ ` (if flag (* ,z ,z) ,z)))
+ ;The parameters x and flag are accessible here.
+ (+ x
+ (fudge x)
+ (fudge (+ x 1)))))
+ The comment "a reference to flag would be to the global variable
+ of the same name" sounds like good behavior for the system to have.
+ but actual specification quoted above says that the actual behavior
+ is undefined.
+
+125:
+ (as reported by Gabe Garza on cmucl-help 2001-09-21)
+ (defvar *tmp* 3)
+ (defun test-pred (x y)
+ (eq x y))
+ (defun test-case ()
+ (let* ((x *tmp*)
+ (func (lambda () x)))
+ (print (eq func func))
+ (print (test-pred func func))
+ (delete func (list func))))
+ Now calling (TEST-CASE) gives output
+ NIL
+ NIL
+ (#<FUNCTION {500A9EF9}>)
+ Evidently Python thinks of the lambda as a code transformation so
+ much that it forgets that it's also an object.
+
+127:
+ The DEFSTRUCT section of the ANSI spec, in the :CONC-NAME section,
+ specifies a precedence rule for name collisions between slot accessors of
+ structure classes related by inheritance. As of 0.7.0, SBCL still
+ doesn't follow it.
+
+129:
+ insufficient syntax checking in MACROLET:
+ (defun foo (x)
+ (macrolet ((defmacro bar (z) `(+ z z)))
+ (bar x)))
+ shouldn't compile without error (because of the extra DEFMACRO symbol).
+
+131:
+ As of sbcl-0.pre7.86.flaky7.3, the cross-compiler, and probably
+ the CL:COMPILE function (which is based on the same %COMPILE
+ mechanism) get confused by
+(defun sxhash (x)
+ (labels ((sxhash-number (x)
+ (etypecase x
+ (fixnum (sxhash x)) ; through DEFTRANSFORM
+ (integer (sb!bignum:sxhash-bignum x))
+ (single-float (sxhash x)) ; through DEFTRANSFORM
+ (double-float (sxhash x)) ; through DEFTRANSFORM
+ #!+long-float (long-float (error "stub: no LONG-FLOAT"))
+ (ratio (let ((result 127810327))
+ (declare (type fixnum result))
+ (mixf result (sxhash-number (numerator x)))
+ (mixf result (sxhash-number (denominator x)))
+ result))
+ (complex (let ((result 535698211))
+ (declare (type fixnum result))
+ (mixf result (sxhash-number (realpart x)))
+ (mixf result (sxhash-number (imagpart x)))
+ result))))
+ (sxhash-recurse (x &optional (depthoid +max-hash-depthoid+))
+ (declare (type index depthoid))
+ (typecase x
+ (list
+ (if (plusp depthoid)
+ (mix (sxhash-recurse (car x) (1- depthoid))
+ (sxhash-recurse (cdr x) (1- depthoid)))
+ 261835505))
+ (instance
+ (if (typep x 'structure-object)
+ (logxor 422371266
+ (sxhash ; through DEFTRANSFORM
+ (class-name (layout-class (%instance-layout x)))))
+ 309518995))
+ (symbol (sxhash x)) ; through DEFTRANSFORM
+ (number (sxhash-number x))
+ (array
+ (typecase x
+ (simple-string (sxhash x)) ; through DEFTRANSFORM
+ (string (%sxhash-substring x))
+ (bit-vector (let ((result 410823708))
+ (declare (type fixnum result))
+ (dotimes (i (min depthoid (length x)))
+ (mixf result (aref x i)))
+ result))
+ (t (logxor 191020317 (sxhash (array-rank x))))))
+ (character
+ (logxor 72185131
+ (sxhash (char-code x)))) ; through DEFTRANSFORM
+ (t 42))))
+ (sxhash-recurse x)))
+ complaining "function called with two arguments, but wants exactly
+ one" about SXHASH-RECURSE. (This might not be strictly a new bug,
+ since IIRC post-fork CMU CL has also had problems with &OPTIONAL
+ arguments in FLET/LABELS: it might be an old Python bug which is
+ only exercised by the new arrangement of the SBCL compiler.)
+
+135:
+ Ideally, uninterning a symbol would allow it, and its associated
+ FDEFINITION and PROCLAIM data, to be reclaimed by the GC. However,
+ at least as of sbcl-0.7.0, this isn't the case. Information about
+ FDEFINITIONs and PROCLAIMed properties is stored in globaldb.lisp
+ essentially in ordinary (non-weak) hash tables keyed by symbols.
+ Thus, once a system has an entry in this system, it tends to live
+ forever, even when it is uninterned and all other references to it
+ are lost.
+
+136:
+ (reported by Arnaud Rouanet on cmucl-imp 2001-12-18)
+ (defmethod foo ((x integer))
+ x)
+ (defmethod foo :around ((x integer))
+ (let ((x (1+ x)))
+ (call-next-method)))
+ Now (FOO 3) should return 3, but instead it returns 4.
+
+140:
+ (reported by Alexey Dejneka sbcl-devel 2002-01-03)
+
+ SUBTYPEP does not work well with redefined classes:
+ ---
+ * (defclass a () ())
+ #<STANDARD-CLASS A>
+ * (defclass b () ())
+ #<STANDARD-CLASS B>
+ * (subtypep 'b 'a)
+ NIL
+ T
+ * (defclass b (a) ())
+ #<STANDARD-CLASS B>
+ * (subtypep 'b 'a)
+ T
+ T
+ * (defclass b () ())
+ #<STANDARD-CLASS B>
+
+ ;;; And now...
+ * (subtypep 'b 'a)
+ T
+ T
+
+ This bug was fixed in sbcl-0.7.4.1 by invalidating the PCL wrapper
+ class upon redefinition. Unfortunately, doing so causes bug #176 to
+ appear. Pending further investication, one or other of these bugs
+ might be present at any given time.
+
+141:
+ Pretty-printing nested backquotes doesn't work right, as
+ reported by Alexey Dejneka sbcl-devel 2002-01-13:
+ * '``(FOO ,@',@S)
+ ``(FOO SB-IMPL::BACKQ-COMMA-AT S)
+ * (lisp-implementation-version)
+ "0.pre7.129"
+
+142:
+ (as reported by Lynn Quam on cmucl-imp ca. 2002-01-16)
+ %NATURALIZE-C-STRING conses a lot, like 16 bytes per byte
+ of the naturalized string. We could probably port the patches
+ from the cmucl-imp mailing list.
+
+143:
+ (reported by Jesse Bouwman 2001-10-24 through the unfortunately
+ prominent SourceForge web/db bug tracking system, which is
+ unfortunately not a reliable way to get a timely response from
+ the SBCL maintainers)
+ In the course of trying to build a test case for an
+ application error, I encountered this behavior:
+ If you start up sbcl, and then lay on CTRL-C for a
+ minute or two, the lisp process will eventually say:
+ %PRIMITIVE HALT called; the party is over.
+ and throw you into the monitor. If I start up lisp,
+ attach to the process with strace, and then do the same
+ (abusive) thing, I get instead:
+ access failure in heap page not marked as write-protected
+ and the monitor again. I don't know enough to have the
+ faintest idea of what is going on here.
+ This is with sbcl 6.12, uname -a reports:
+ Linux prep 2.2.19 #4 SMP Tue Apr 24 13:59:52 CDT 2001 i686 unknown
+ I (WHN) have verified that the same thing occurs on sbcl-0.pre7.141
+ under OpenBSD 2.9 on my X86 laptop. Do be patient when you try it:
+ it took more than two minutes (but less than five) for me.
+
+144:
+ (This was once known as IR1-4, but it lived on even after the
+ IR1 interpreter went to the big bit bucket in the sky.)
+ The system accepts DECLAIM in most places where DECLARE would be
+ accepted, without even issuing a warning. ANSI allows this, but since
+ it's fairly easy to mistype DECLAIM instead of DECLARE, and the
+ meaning is rather different, and it's unlikely that the user
+ has a good reason for doing DECLAIM not at top level, it would be
+ good to issue a STYLE-WARNING when this happens. A possible
+ fix would be to issue STYLE-WARNINGs for DECLAIMs not at top level,
+ or perhaps to issue STYLE-WARNINGs for any EVAL-WHEN not at top level.
+ [This is considered an IR1-interpreter-related bug because until
+ EVAL-WHEN is rewritten, which won't happen until after the IR1
+ interpreter is gone, the system's notion of what's a top-level form
+ and what's not will remain too confused to fix this problem.]
+
+145:
+ ANSI allows types `(COMPLEX ,FOO) to use very hairy values for
+ FOO, e.g. (COMPLEX (AND REAL (SATISFIES ODDP))). The old CMU CL
+ COMPLEX implementation didn't deal with this, and hasn't been
+ upgraded to do so. (This doesn't seem to be a high priority
+ conformance problem, since seems hard to construct useful code
+ where it matters.)
+
+146:
+ Floating point errors are reported poorly. E.g. on x86 OpenBSD
+ with sbcl-0.7.1,
+ * (expt 2.0 12777)
+ debugger invoked on condition of type SB-KERNEL:FLOATING-POINT-EXCEPTION:
+ An arithmetic error SB-KERNEL:FLOATING-POINT-EXCEPTION was signalled.
+ No traps are enabled? How can this be?
+ It should be possible to be much more specific (overflow, division
+ by zero, etc.) and of course the "How can this be?" should be fixable.
+
+ See also bugs #45.c and #183
+
+148:
+ In sbcl-0.7.1.3 on x86, COMPILE-FILE on the file
+ (in-package :cl-user)
+ (defvar *thing*)
+ (defvar *zoom*)
+ (defstruct foo bar bletch)
+ (defun %zeep ()
+ (labels ((kidify1 (kid)
+ )
+ (kid-frob (kid)
+ (if *thing*
+ (setf sweptm
+ (m+ (frobnicate kid)
+ sweptm))
+ (kidify1 kid))))
+ (declare (inline kid-frob))
+ (map nil
+ #'kid-frob
+ (the simple-vector (foo-bar perd)))))
+ fails with
+ debugger invoked on condition of type TYPE-ERROR:
+ The value NIL is not of type SB-C::NODE.
+ The location of this failure has moved around as various related
+ issues were cleaned up. As of sbcl-0.7.1.9, it occurs in
+ NODE-BLOCK called by LAMBDA-COMPONENT called by IR2-CONVERT-CLOSURE.
+
+153:
+ (essentially the same problem as a CMU CL bug reported by Martin
+ Cracauer on cmucl-imp 2002-02-19)
+ There is a hole in structure slot type checking. Compiling and LOADing
+ (declaim (optimize safety))
+ (defstruct foo
+ (bla 0 :type fixnum))
+ (defun f ()
+ (let ((foo (make-foo)))
+ (setf (foo-bla foo) '(1 . 1))
+ (format t "Is ~a of type ~a a cons? => ~a~%"
+ (foo-bla foo)
+ (type-of (foo-bla foo))
+ (consp (foo-bla foo)))))
+ (f)
+ should signal an error, but in sbcl-0.7.1.21 instead gives the output
+ Is (1 . 1) of type CONS a cons? => NIL
+ without signalling an error.
+
+157:
+ Functions SUBTYPEP, TYPEP, UPGRADED-ARRAY-ELEMENT-TYPE, and
+ UPGRADED-COMPLEX-PART-TYPE should have an optional environment argument.
+ (reported by Alexey Dejneka sbcl-devel 2002-04-12)
+
+162:
+ (reported by Robert E. Brown 2002-04-16)
+ When a function is called with too few arguments, causing the
+ debugger to be entered, the uninitialized slots in the bad call frame
+ seem to cause GCish problems, being interpreted as tagged data even
+ though they're not. In particular, executing ROOM in the
+ debugger at that point causes AVER failures:
+ * (machine-type)
+ "X86"
+ * (lisp-implementation-version)
+ "0.7.2.12"
+ * (typep 10)
+ ...
+ 0] (room)
+ ...
+ failed AVER: "(SAP= CURRENT END)"
+ (Christophe Rhodes reports that this doesn't occur on the SPARC, which
+ isn't too surprising since there are many differences in stack
+ implementation and GC conservatism between the X86 and other ports.)
+
+166:
+ Compiling
+ (in-package :cl-user)
+ (defstruct uustk)
+ (defmethod permanentize ((uustk uustk))
+ (flet ((frob (hash-table test-for-deletion)
+ )
+ (obj-entry.stale? (oe)
+ (destructuring-bind (key . datum) oe
+ (declare (type simple-vector key))
+ (deny0 (void? datum))
+ (some #'stale? key))))
+ (declare (inline frob obj-entry.stale?))
+ (frob (uustk.args-hash->obj-alist uustk)
+ #'obj-entry.stale?)
+ (frob (uustk.hash->memoized-objs-list uustk)
+ #'objs.stale?))
+ (call-next-method))
+ in sbcl-0.7.3.11 causes an assertion failure,
+ failed AVER:
+ "(NOT
+(AND (NULL (BLOCK-SUCC B))
+ (NOT (BLOCK-DELETE-P B))
+ (NOT (EQ B (COMPONENT-HEAD #)))))"
+
+167:
+ In sbcl-0.7.3.11, compiling the (illegal) code
+ (in-package :cl-user)
+ (defmethod prove ((uustk uustk))
+ (zap ((frob () nil))
+ (frob)))
+ gives the (not terribly clear) error message
+ ; caught ERROR:
+ ; (during macroexpansion of (DEFMETHOD PROVE ...))
+ ; can't get template for (FROB NIL NIL)
+ The problem seems to be that the code walker used by the DEFMETHOD
+ macro is unhappy with the illegal syntax in the method body, and
+ is giving an unclear error message.
+
+168:
+ (reported by Dan Barlow on sbcl-devel 2002-05-10)
+ In sbcl-0.7.3.12, doing
+ (defstruct foo bar baz)
+ (compile nil (lambda (x) (or x (foo-baz x))))
+ gives an error
+ debugger invoked on condition of type SB-INT:BUG:
+ full call to SB-KERNEL:%INSTANCE-REF
+ This is probably a bug in SBCL itself. [...]
+ Since this is a reasonable user error, it shouldn't be reported as
+ an SBCL bug.
+
+171:
+ (reported by Pierre Mai while investigating bug 47):
+ (DEFCLASS FOO () ((A :SILLY T)))
+ signals a SIMPLE-ERROR, not a PROGRAM-ERROR.
+
+172:
+ sbcl's treatment of at least macro lambda lists is too permissive;
+ e.g., in sbcl-0.7.3.7:
+ (defmacro foo (&rest rest bar) `(,bar ,rest))
+ (macroexpand '(foo quux zot)) -> (QUUX (QUUX ZOT))
+ whereas section 3.4.4 of the CLHS doesn't allow required parameters
+ to come after the rest argument.
+
+173:
+ The compiler sometimes tries to constant-fold expressions before
+ it checks to see whether they can be reached. This can lead to
+ bogus warnings about errors in the constant folding, e.g. in code
+ like
+ (WHEN X
+ (WRITE-STRING (> X 0) "+" "0"))
+ compiled in a context where the compiler can prove that X is NIL,
+ and the compiler complains that (> X 0) causes a type error because
+ NIL isn't a valid argument to #'>. Until sbcl-0.7.4.10 or so this
+ caused a full WARNING, which made the bug really annoying because then
+ COMPILE and COMPILE-FILE returned FAILURE-P=T for perfectly legal
+ code. Since then the warning has been downgraded to STYLE-WARNING,
+ so it's still a bug but at least it's a little less annoying.
+
+174:
+ The error message from attempting to use a #\Return format
+ directive:
+ (format nil "~^M") ; replace "^M" with a literal #\Return
+ debugger invoked on condition of type SB-FORMAT::FORMAT-ERROR:
+ error in format: unknown format directive
+ ~
+ ^
+ is not terribly helpful; this is more noticeable than parallel cases
+ with e.g. #\Backspace because of the differing newline conventions
+ on various operating systems. (reported by Harald Hanche-Olsen on
+ cmucl-help 2002-05-31)
+
+176:
+ reported by Alexey Dejneka 08 Jun 2002 in sbcl-devel:
+ Playing with McCLIM, I've received an error "Unbound variable WRAPPER
+ in SB-PCL::CHECK-WRAPPER-VALIDITY".
+ (defun check-wrapper-validity (instance)
+ (let* ((owrapper (wrapper-of instance)))
+ (if (not (invalid-wrapper-p owrapper))
+ owrapper
+ (let* ((state (wrapper-state wrapper)) ; !!!
+ ...
+ I've tried to replace it with OWRAPPER, but now OBSOLETE-INSTANCE-TRAP
+ breaks with "NIL is not of type SB-KERNEL:LAYOUT".
+ SBCL 0.7.4.13.
+ partial fix: The undefined variable WRAPPER resulted from an error
+ in recent refactoring, as can be seen by comparing to the code in e.g.
+ sbcl-0.7.2. Replacing WRAPPER with OWRAPPER (done by WHN in sbcl-0.7.4.22)
+ should bring the code back to its behavior as of sbcl-0.7.2, but
+ that still leaves the OBSOLETE-INSTANCE-TRAP bug. An example of
+ input which triggers that bug is
+ (dotimes (i 20)
+ (let ((lastname (intern (format nil "C~D" (1- i))))
+ (name (intern (format nil "C~D" i))))
+ (eval `(defclass ,name
+ (,@(if (= i 0) nil (list lastname)))
+ ()))
+ (eval `(defmethod initialize-instance :after ((x ,name) &rest any)
+ (declare (ignore any))))))
+ (defclass b () ())
+ (defclass c0 (b) ())
+ (make-instance 'c19)
+
+ See also bug #140.
+
+178: "AVER failure compiling confused THEs in FUNCALL"
+ In sbcl-0.7.4.24, compiling
+ (defun bug178 (x)
+ (funcall (the function (the standard-object x))))
+ gives
+ failed AVER:
+ "(AND (EQ (IR2-CONTINUATION-PRIMITIVE-TYPE 2CONT) FUNCTION-PTYPE) (EQ CHECK T))"
+ This variant compiles OK, though:
+ (defun bug178alternative (x)
+ (funcall (the nil x)))
+
+181: "bad type specifier drops compiler into debugger"
+ Compiling
+ (in-package :cl-user)
+ (defun bar (x)
+ (declare (type 0 x))
+ (cons x x))
+ signals
+ bad thing to be a type specifier: 0
+ which seems fine, but also enters the debugger (instead of having
+ the compiler handle the error, convert it into a COMPILER-ERROR, and
+ continue compiling) which seems wrong.
+
+183: "IEEE floating point issues"
+ Even where floating point handling is being dealt with relatively
+ well (as of sbcl-0.7.5, on sparc/sunos and alpha; see bug #146), the
+ accrued-exceptions and current-exceptions part of the fp control
+ word don't seem to bear much relation to reality. E.g. on
+ SPARC/SunOS:
+ * (/ 1.0 0.0)
+
+ debugger invoked on condition of type DIVISION-BY-ZERO:
+ arithmetic error DIVISION-BY-ZERO signalled
+ 0] (sb-vm::get-floating-point-modes)
+
+ (:TRAPS (:OVERFLOW :INVALID :DIVIDE-BY-ZERO)
+ :ROUNDING-MODE :NEAREST
+ :CURRENT-EXCEPTIONS NIL
+ :ACCRUED-EXCEPTIONS (:INEXACT)
+ :FAST-MODE NIL)
+ 0] abort
+ * (sb-vm::get-floating-point-modes)
+ (:TRAPS (:OVERFLOW :INVALID :DIVIDE-BY-ZERO)
+ :ROUNDING-MODE :NEAREST
+ :CURRENT-EXCEPTIONS (:INEXACT)
+ :ACCRUED-EXCEPTIONS (:INEXACT)
+ :FAST-MODE NIL)
+
+185: "top-level forms at the REPL"
+ * (locally (defstruct foo (a 0 :type fixnum)))
+ gives an error:
+ ; caught ERROR:
+ ; (in macroexpansion of (SB-KERNEL::%DELAYED-GET-COMPILER-LAYOUT BAR))
+ however, compiling and loading the same expression in a file works
+ as expected.
+
+187: "type inference confusion around DEFTRANSFORM time"
+ (reported even more verbosely on sbcl-devel 2002-06-28 as "strange
+ bug in DEFTRANSFORM")
+ After the file below is compiled and loaded in sbcl-0.7.5, executing
+ (TCX (MAKE-ARRAY 4 :FILL-POINTER 2) 0)
+ at the REPL returns an adjustable vector, which is wrong. Presumably
+ somehow the DERIVE-TYPE information for the output values of %WAD is
+ being mispropagated as a type constraint on the input values of %WAD,
+ and so causing the type test to be optimized away. It's unclear how
+ hand-expanding the DEFTRANSFORM would change this, but it suggests
+ the DEFTRANSFORM machinery (or at least the way DEFTRANSFORMs are
+ invoked at a particular phase) is involved.
+ (cl:in-package :sb-c)
+ (eval-when (:compile-toplevel)
+ ;;; standin for %DATA-VECTOR-AND-INDEX
+ (defknown %dvai (array index)
+ (values t t)
+ (foldable flushable))
+ (deftransform %dvai ((array index)
+ (vector t)
+ *
+ :important t)
+ (let* ((atype (continuation-type array))
+ (eltype (array-type-specialized-element-type atype)))
+ (when (eq eltype *wild-type*)
+ (give-up-ir1-transform
+ "specialized array element type not known at compile-time"))
+ (when (not (array-type-complexp atype))
+ (give-up-ir1-transform "SIMPLE array!"))
+ `(if (array-header-p array)
+ (%wad array index nil)
+ (values array index))))
+ ;;; standin for %WITH-ARRAY-DATA
+ (defknown %wad (array index (or index null))
+ (values (simple-array * (*)) index index index)
+ (foldable flushable))
+ ;;; (Commenting out this optimizer causes the bug to go away.)
+ (defoptimizer (%wad derive-type) ((array start end))
+ (let ((atype (continuation-type array)))
+ (when (array-type-p atype)
+ (values-specifier-type
+ `(values (simple-array ,(type-specifier
+ (array-type-specialized-element-type atype))
+ (*))
+ index index index)))))
+ ) ; EVAL-WHEN
+ (defun %wad (array start end)
+ (format t "~&in %WAD~%")
+ (%with-array-data array start end))
+ (cl:in-package :cl-user)
+ (defun tcx (v i)
+ (declare (type (vector t) v))
+ (declare (notinline sb-kernel::%with-array-data))
+ ;; (Hand-expending DEFTRANSFORM %DVAI here also causes the bug to
+ ;; go away.)
+ (sb-c::%dvai v i))
+
+188: "compiler performance fiasco involving type inference and UNION-TYPE"
+ (In sbcl-0.7.6.10, DEFTRANSFORM CONCATENATE was commented out until this
+ bug could be fixed properly, so you won't see the bug unless you restore
+ the DEFTRANSFORM by hand.) In sbcl-0.7.5.11 on a 700 MHz Pentium III,
+ (time (compile
+ nil
+ '(lambda ()
+ (declare (optimize (safety 3)))
+ (declare (optimize (compilation-speed 2)))
+ (declare (optimize (speed 1) (debug 1) (space 1)))
+ (let ((fn "if-this-file-exists-the-universe-is-strange"))
+ (load fn :if-does-not-exist nil)
+ (load (concatenate 'string fn ".lisp") :if-does-not-exist nil)
+ (load (concatenate 'string fn ".fasl") :if-does-not-exist nil)
+ (load (concatenate 'string fn ".misc-garbage")
+ :if-does-not-exist nil)))))
+ reports
+ 134.552 seconds of real time
+ 133.35156 seconds of user run time
+ 0.03125 seconds of system run time
+ [Run times include 2.787 seconds GC run time.]
+ 0 page faults and
+ 246883368 bytes consed.
+ BACKTRACE from Ctrl-C in the compilation shows that the compiler is
+ thinking about type relationships involving types like
+ #<UNION-TYPE
+ (OR (INTEGER 576 576)
+ (INTEGER 1192 1192)
+ (INTEGER 2536 2536)
+ (INTEGER 1816 1816)
+ (INTEGER 2752 2752)
+ (INTEGER 1600 1600)
+ (INTEGER 2640 2640)
+ (INTEGER 1808 1808)
+ (INTEGER 1296 1296)
+ ...)>)[:EXTERNAL]
+
+190: "PPC/Linux pipe? buffer? bug"
+ In sbcl-0.7.6, the run-program.test.sh test script sometimes hangs
+ on the PPC/Linux platform, waiting for a zombie env process. This
+ is a classic symptom of buffer filling and deadlock, but it seems
+ only sporadically reproducible.
+
+191: "Miscellaneous PCL deficiencies"
+ (reported by Alexey Dejneka sbcl-devel 2002-08-04)
+ a. DEFCLASS does not inform the compiler about generated
+ functions. Compiling a file with
+ (DEFCLASS A-CLASS ()
+ ((A-CLASS-X)))
+ (DEFUN A-CLASS-X (A)
+ (WITH-SLOTS (A-CLASS-X) A
+ A-CLASS-X))
+ results in a STYLE-WARNING:
+ undefined-function
+ SB-SLOT-ACCESSOR-NAME::|COMMON-LISP-USER A-CLASS-X slot READER|
+
+ APD's fix for this was checked in to sbcl-0.7.6.20, but Pierre
+ Mai points out that the declamation of functions is in fact
+ incorrect in some cases (most notably for structure
+ classes). This means that at present erroneous attempts to use
+ WITH-SLOTS and the like on classes with metaclass STRUCTURE-CLASS
+ won't get the corresponding STYLE-WARNING.
+ c. the examples in CLHS 7.6.5.1 (regarding generic function lambda
+ lists and &KEY arguments) do not signal errors when they should.
+
+192: "Python treats free type declarations as promises."
+ a. original report by Alexey Dejneka (on sbcl-devel 2002-08-26):
+ (declaim (optimize (speed 0) (safety 3)))
+ (defun f (x)
+ (declare (real x))
+ (+ x
+ (locally (declare (single-float x))
+ (sin x))))
+ Now (F NIL) correctly gives a type error, but (F 100) gives
+ a segmentation violation.
+ b. same fundamental problem in a different way, easy to stumble
+ across if you mistype and declare the wrong index in
+ (DOTIMES (I ...) (DOTIMES (J ...) (DECLARE ...) ...)):
+ (declaim (optimize (speed 1) (safety 3)))
+ (defun trust-assertion (i)
+ (dotimes (j i)
+ (declare (type (mod 4) i)) ; when commented out, behavior changes!
+ (unless (< i 5)
+ (print j))))
+ (trust-assertion 6) ; prints nothing unless DECLARE is commented out
+
+193: "unhelpful CLOS error reporting when the primary method is missing"
+ In sbcl-0.7.7, when
+ (defmethod foo :before ((x t)) (print x))
+ is the only method defined on FOO, the error reporting when e.g.
+ (foo 12)
+ is relatively unhelpful:
+ There is no primary method for the generic function
+ #<STANDARD-GENERIC-FUNCTION FOO (1)>.
+ with the offending argument nowhere visible in the backtrace. This
+ continues even if there *are* primary methods, just not for the
+ specified arg type, e.g.
+ (defmethod foo ((x character)) (print x))
+ (defmethod foo ((x string)) (print x))
+ (defmethod foo ((x pathname)) ...)
+ In that case it could be very helpful to know what argument value is
+ falling through the cracks of the defined primary methods, but the
+ error message stays the same (even BACKTRACE doesn't tell you what the
+ bad argument value is).
+
+194: "no error from (THE REAL '(1 2 3)) in some cases"
+ In sbcl-0.7.7.9,
+ (multiple-value-prog1 (progn (the real '(1 2 3))))
+ returns (1 2 3) instead of signalling an error. Also in sbcl-0.7.7.9,
+ a more complicated instance of this bug kept
+ (IGNORE-ERRORS (MIN '(1 2 3))) from returning NIL as it should when
+ the MIN source transform expanded to (THE REAL '(1 2 3)), because
+ (IGNORE-ERRORS (THE REAL '(1 2 3))) returns (1 2 3).
+ Alexey Dejneka pointed out that
+ (IGNORE-ERRORS (IDENTITY (THE REAL '(1 2 3)))) works as it should.
+ (IGNORE-ERRORS (VALUES (THE REAL '(1 2 3)))) also works as it should.
+ Perhaps this is another case of VALUES type intersections behaving
+ in non-useful ways?
+ When I (WHN) tried to use the VALUES trick to work around this bug
+ in the MIN source transform, it didn't work for
+ (assert (null (ignore-errors (min 1 #(1 2 3)))))
+ Hand-expanding the source transform, I get
+ (assert (null (ignore-errors
+ (let ((arg1 1)
+ (arg2 (identity (the real #(1 2 3)))))
+ (if (< arg1 arg2) arg1 arg2)))))
+ which fails (i.e. the assertion fails, because the IGNORE-ERRORS
+ doesn't report MIN signalling a type error). At the REPL
+ (null (ignore-errors
+ (let ((arg1 1)
+ (arg2 (identity (the real #(1 2 3)))))
+ (if (< arg1 arg2) arg1 arg2))))
+ => T
+ but when this expression is used as the body of (DEFUN FOO () ...)
+ then (FOO)=>NIL.
+
+195: "confusing reporting of not-a-REAL TYPE-ERRORs from THE REAL"
+ In sbcl-0.7.7.10, (THE REAL #(1 2 3)) signals a type error which
+ prints as "This is not a (OR SINGLE-FLOAT DOUBLE-FLOAT RATIONAL)".
+ The (OR SINGLE-FLOAT DOUBLE-FLOAT RATIONAL) representation of
+ REAL is unnecessarily confusing, especially since it relies on
+ internal implementation knowledge that even with SHORT-FLOAT
+ and LONG-FLOAT left out of the union, this type is equal to REAL.
+ So it'd be better just to say "This is not a REAL".
+
+DEFUNCT CATEGORIES OF BUGS
+ IR1-#:
+ These labels were used for bugs related to the old IR1 interpreter.
+ The # values reached 6 before the category was closed down.