other reasons, e.g. because they were moved elsewhere).
-KNOWN BUGS OF NO SPECIAL CLASS:
-
2:
DEFSTRUCT almost certainly should overwrite the old LAYOUT information
instead of just punting when a contradictory structure definition
program, even if you know or guess enough about the internals of
SBCL to wager that this (undefined in ANSI) operation would be safe.
-3:
+3: "type checking of structure slots"
+ a:
ANSI specifies that a type mismatch in a structure slot
initialization value should not cause a warning.
WORKAROUND:
Such code should compile without complaint and work correctly either
on SBCL or on any other completely compliant Common Lisp system.
-6:
- bogus warnings about undefined functions for magic functions like
- SB!C::%%DEFUN and SB!C::%DEFCONSTANT when cross-compiling files
- like src/code/float.lisp. Fixing this will probably require
- straightening out enough bootstrap consistency issues that
- the cross-compiler can run with *TYPE-SYSTEM-INITIALIZED*.
- Instead, the cross-compiler runs in a slightly flaky state
- which is sane enough to compile SBCL itself, but which is
- also unstable in several ways, including its inability
- to really grok function declarations.
-
- As of sbcl-0.7.5, sbcl's cross-compiler does run with
- *TYPE-SYSTEM-INITIALIZED*; however, this bug remains.
-
-7:
- The "compiling top-level form:" output ought to be condensed.
- Perhaps any number of such consecutive lines ought to turn into a
- single "compiling top-level forms:" line.
-
-10:
- The way that the compiler munges types with arguments together
- with types with no arguments (in e.g. TYPE-EXPAND) leads to
- weirdness visible to the user:
- (DEFTYPE FOO () 'FIXNUM)
- (TYPEP 11 'FOO) => T
- (TYPEP 11 '(FOO)) => T, which seems weird
- (TYPEP 11 'FIXNUM) => T
- (TYPEP 11 '(FIXNUM)) signals an error, as it should
- The situation is complicated by the presence of Common Lisp types
- like UNSIGNED-BYTE (which can either be used in list form or alone)
- so I'm not 100% sure that the behavior above is actually illegal.
- But I'm 90+% sure, and the following related behavior,
- (TYPEP 11 'AND) => T
- treating the bare symbol AND as equivalent to '(AND), is specifically
- forbidden (by the ANSI specification of the AND type).
-
-11:
- It would be nice if the
- caught ERROR:
- (during macroexpansion)
- said what macroexpansion was at fault, e.g.
- caught ERROR:
- (during macroexpansion of IN-PACKAGE,
- during macroexpansion of DEFFOO)
-
-15:
- (SUBTYPEP '(FUNCTION (T BOOLEAN) NIL)
- '(FUNCTION (FIXNUM FIXNUM) NIL)) => T, T
- (Also, when this is fixed, we can enable the code in PROCLAIM which
- checks for incompatible FTYPE redeclarations.)
-
-19:
- (I *think* this is a bug. It certainly seems like strange behavior. But
- the ANSI spec is scary, dark, and deep.. -- WHN)
- (FORMAT NIL "~,1G" 1.4) => "1. "
- (FORMAT NIL "~3,1G" 1.4) => "1. "
-
-20:
- from Marco Antoniotti on cmucl-imp mailing list 1 Mar 2000:
- (defclass ccc () ())
- (setf (find-class 'ccc1) (find-class 'ccc))
- (defmethod zut ((c ccc1)) 123)
- In sbcl-0.7.1.13, this gives an error,
- There is no class named CCC1.
- DTC's recommended workaround from the mailing list 3 Mar 2000:
- (setf (pcl::find-class 'ccc1) (pcl::find-class 'ccc))
-
-27:
- Sometimes (SB-EXT:QUIT) fails with
- Argh! maximum interrupt nesting depth (4096) exceeded, exiting
- Process inferior-lisp exited abnormally with code 1
- I haven't noticed a repeatable case of this yet.
-
-32:
- The printer doesn't report closures very well. This is true in
- CMU CL 18b as well:
- (PRINT #'CLASS-NAME)
- gives
- #<Closure Over Function "DEFUN STRUCTURE-SLOT-ACCESSOR" {134D1A1}>
- It would be nice to make closures have a settable name slot,
- and make things like DEFSTRUCT and FLET, which create closures,
- set helpful values into this slot.
-
33:
And as long as we're wishing, it would be awfully nice if INSPECT could
also report on closures, telling about the values of the bound variables.
+ Currently INSPECT and DESCRIBE do show the values, but showing the
+ names of the bindings would be even nicer.
+
35:
The compiler assumes that any time a function of declared FTYPE
doesn't signal an error, its arguments were of the declared type.
(FOO 1.5)
will cause the INTEGERP case to be selected, giving bogus output a la
exactly 2.5
- (or (FOO 1000.5), "exactly 1001.5")
This violates the "declarations are assertions" principle.
According to the ANSI spec, in the section "System Class FUNCTION",
this is a case of "lying to the compiler", but the lying is done
(Also, verify that the compiler handles declared function
return types as assertions.)
-41:
- TYPEP of VALUES types is sometimes implemented very inefficiently, e.g. in
- (DEFTYPE INDEXOID () '(INTEGER 0 1000))
- (DEFUN FOO (X)
- (DECLARE (TYPE INDEXOID X))
- (THE (VALUES INDEXOID)
- (VALUES X)))
- where the implementation of the type check in function FOO
- includes a full call to %TYPEP. There are also some fundamental problems
- with the interpretation of VALUES types (inherited from CMU CL, and
- from the ANSI CL standard) as discussed on the cmucl-imp@cons.org
- mailing list, e.g. in Robert Maclachlan's post of 21 Jun 2000.
-
42:
The definitions of SIGCONTEXT-FLOAT-REGISTER and
%SET-SIGCONTEXT-FLOAT-REGISTER in x86-vm.lisp say they're not
so they could be supported after all. Very likely
SIGCONTEXT-FLOATING-POINT-MODES could now be supported, too.
-43:
- (as discussed by Douglas Crosher on the cmucl-imp mailing list ca.
- Aug. 10, 2000): CMUCL currently interprets 'member as '(member); same
- issue with 'union, 'and, 'or etc. So even though according to the
- ANSI spec, bare 'MEMBER, 'AND, and 'OR are not legal types, CMUCL
- (and now SBCL) interpret them as legal types.
-
-45:
- a slew of floating-point-related errors reported by Peter Van Eynde
- on July 25, 2000:
- b: SBCL's value for LEAST-POSITIVE-SHORT-FLOAT is bogus, and
- should probably be 1.4012985e-45. In SBCL,
- (/ LEAST-POSITIVE-SHORT-FLOAT 2) returns a number smaller
- than LEAST-POSITIVE-SHORT-FLOAT. Similar problems
- exist for LEAST-NEGATIVE-SHORT-FLOAT, LEAST-POSITIVE-LONG-FLOAT,
- and LEAST-NEGATIVE-LONG-FLOAT.
- c: Many expressions generate floating infinity on x86/Linux:
- (/ 1 0.0)
- (/ 1 0.0d0)
- (EXPT 10.0 1000)
- (EXPT 10.0d0 1000)
- PVE's regression tests want them to raise errors. sbcl-0.7.0.5
- on x86/Linux generates the infinities instead. That might or
- might not be conforming behavior, but it's also inconsistent,
- which is almost certainly wrong. (Inconsistency: (/ 1 0.0)
- should give the same result as (/ 1.0 0.0), but instead (/ 1 0.0)
- generates SINGLE-FLOAT-POSITIVE-INFINITY and (/ 1.0 0.0)
- signals an error.
- d: (in section12.erg) various forms a la
- (FLOAT 1 DOUBLE-FLOAT-EPSILON)
- don't give the right behavior.
-
-46:
- type safety errors reported by Peter Van Eynde July 25, 2000:
- c: (COERCE 'AND 'FUNCTION) returns something related to
- (MACRO-FUNCTION 'AND), but ANSI says it should raise an error.
- h: (MAKE-CONCATENATED-STREAM (MAKE-STRING-OUTPUT-STREAM))
- should signal TYPE-ERROR.
- i: MAKE-TWO-WAY-STREAM doesn't check that its arguments can
- be used for input and output as needed. It should fail with
- TYPE-ERROR when handed e.g. the results of
- MAKE-STRING-INPUT-STREAM or MAKE-STRING-OUTPUT-STREAM in
- the inappropriate positions, but doesn't.
- k: READ-BYTE is supposed to signal TYPE-ERROR when its argument is
- not a binary input stream, but instead cheerfully reads from
- character streams, e.g. (MAKE-STRING-INPUT-STREAM "abc").
-
-47:
- DEFCLASS bugs reported by Peter Van Eynde July 25, 2000:
- d: (DEFGENERIC IF (X)) should signal a PROGRAM-ERROR, but instead
- causes a COMPILER-ERROR.
-
-48:
- SYMBOL-MACROLET bugs reported by Peter Van Eynde July 25, 2000:
- c: SYMBOL-MACROLET should signal PROGRAM-ERROR if something
- it binds is declared SPECIAL inside.
-
-51:
- miscellaneous errors reported by Peter Van Eynde July 25, 2000:
- a: (PROGN
- (DEFGENERIC FOO02 (X))
- (DEFMETHOD FOO02 ((X NUMBER)) T)
- (LET ((M (FIND-METHOD (FUNCTION FOO02)
- NIL
- (LIST (FIND-CLASS (QUOTE NUMBER))))))
- (REMOVE-METHOD (FUNCTION FOO02) M)
- (DEFGENERIC FOO03 (X))
- (ADD-METHOD (FUNCTION FOO03) M)))
- should give an error, but SBCL allows it.
-
-52:
- It has been reported (e.g. by Peter Van Eynde) that there are
- several metaobject protocol "errors". (In order to fix them, we might
- need to document exactly what metaobject protocol specification
- we're following -- the current code is just inherited from PCL.)
-
-54:
- The implementation of #'+ returns its single argument without
- type checking, e.g. (+ "illegal") => "illegal".
-
-60:
- The debugger LIST-LOCATIONS command doesn't work properly.
-
61:
Compiling and loading
(DEFUN FAIL (X) (THROW 'FAIL-TAG X))
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.
+ (this is apparently mostly fixed on the SPARC, PPC, and x86 architectures:
+ while giving the backtrace the non-x86 systems complains about "unknown
+ source location: using block start", but apart from that the
+ backtrace seems reasonable. On x86 this is masked by bug 353. See
+ tests/debug.impure.lisp for a test case)
64:
Using the pretty-printer from the command prompt gives funny
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.
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.
+ (Actually this has changed changed since, and types as above are
+ now supported. This may be a bug.)
83:
RANDOM-INTEGER-EXTRA-BITS=10 may not be large enough for the RANDOM
(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.
+ In fact, the type system is likely to depend on this inequality not
+ holding... * is not equivalent to T in many cases, such as
+ (VECTOR *) /= (VECTOR T).
98:
In sbcl-0.6.11.41 (and in all earlier SBCL, and in CMU
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
+ To exercise the problem, compile and load
+ (cl:in-package :cl-user)
+ (defstruct foo
+ (bar (error "missing") :type bar))
+ (defvar *foo*)
+ (defun wastrel1 (x)
+ (loop (setf (foo-bar *foo*) x)))
+ (defstruct bar)
+ (defvar *bar* (make-bar))
+ (defvar *foo* (make-foo :bar *bar*))
+ (defvar *setf-foo-bar* #'(setf foo-bar))
+ (defun wastrel2 (x)
+ (loop (funcall *setf-foo-bar* x *foo*)))
+ then run (WASTREL1 *BAR*) or (WASTREL2 *BAR*), hit Ctrl-C, and
+ use BACKTRACE, to see it's spending all essentially all its time
+ in %TYPEP and VALUES-SPECIFIER-TYPE and so forth.
+ One possible solution would be simply to give up on
+ representing structure slot accessors as functions, and represent
+ them as macroexpansions instead. This can be inconvenient for users,
+ but it's not clear that it's worse than trying to help by expanding
+ into a horribly inefficient implementation.
+ 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)
+ (or #+sbcl (and (sb-int: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
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.
-
-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)"
+ ROOM issues:
+
+ a) ROOM works by walking over the heap linearly, instead of
+ following the object graph. Hence, it report garbage objects that
+ are unreachable. (Maybe this is a feature and not a bug?)
+
+ b) ROOM uses MAP-ALLOCATED-OBJECTS to walk the heap, which doesn't
+ check all pointers as well as it should, and can hence become
+ confused, leading to aver failures. As of 1.0.13.21 these (the
+ SAP= aver in particular) should be mostly under control, but push
+ ROOM hard enough and it still might croak.
117:
When the compiler inline expands functions, it may be that different
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.
+ (see also bug 279)
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
+ 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.
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.
+ lexical environment.
Then it seems to contradict itself by giving the example
(defun foo (x flag)
(macrolet ((fudge (z)
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).
+ (Since 0.7.8.23 macroexpanders are defined in a restricted version
+ of the lexical environment, containing no lexical variables and
+ functions, which seems to conform to ANSI and CLtL2, but signalling
+ a STYLE-WARNING for references to variables similar to locals might
+ be a good thing.)
135:
Ideally, uninterning a symbol would allow it, and its associated
- FDEFINITION and PROCLAIM data, to be reclaimed by the GC. However,
+ 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.]
+ are lost.
145:
+ a.
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
conformance problem, since seems hard to construct useful code
where it matters.)
+ [ partially fixed by CSR in 0.8.17.17 because of a PFD ansi-tests
+ report that (COMPLEX RATIO) was failing; still failing on types of
+ the form (AND NUMBER (SATISFIES REALP) (SATISFIES ZEROP)). ]
+
+ b. (fixed in 0.8.3.43)
+
146:
Floating point errors are reported poorly. E.g. on x86 OpenBSD
with sbcl-0.7.1,
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
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.
-
-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.
+ (Can't reproduce on x86 linux as of 1.0.20.23 - MGL)
+
+ This is probably the same bug as 216
173:
The compiler sometimes tries to constant-fold expressions before
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.
-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)))
-
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 (: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.
+ (declare (optimize (safety 3)))
+ (declare (optimize (compilation-speed 2)))
+ (declare (optimize (speed 1) (debug 1) (space 1)))
+ (let ((start 4))
+ (declare (type (integer 0) start))
+ (print (incf start 22))
+ (print (incf start 26))
+ (print (incf start 28)))
+ (let ((start 6))
+ (declare (type (integer 0) start))
+ (print (incf start 22))
+ (print (incf start 26)))
+ (let ((start 10))
+ (declare (type (integer 0) start))
+ (print (incf start 22))
+ (print (incf start 26))))))
+
+ [ Update: 1.0.14.36 improved this quite a bit (20-25%) by
+ eliminating useless work from PROPAGATE-FROM-SETS -- but as alluded
+ below, maybe we should be smarter about when to decide a derived
+ type is "good enough". ]
+
+ This example could be solved with clever enough constraint
+ propagation or with SSA, but consider
+
+ (let ((x 0))
+ (loop (incf x 2)))
+
+ The careful type of X is {2k} :-(. Is it really important to be
+ able to work with unions of many intervals?
191: "Miscellaneous PCL deficiencies"
(reported by Alexey Dejneka sbcl-devel 2002-08-04)
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."
- b. What seemed like the same fundamental problem as bug 192a, but
- was not fixed by the same (APD "more strict type checking
- sbcl-devel 2002-08-97) patch:
- (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"
- fixed parts:
- a. In sbcl-0.7.7.9,
- (multiple-value-prog1 (progn (the real '(1 2 3))))
- returns (1 2 3) instead of signalling an error. This was fixed by
- APD's "more strict type checking patch", but although the fixed
- code (in sbcl-0.7.7.19) works (signals TYPE-ERROR) interactively,
- it's difficult to write a regression test for it, because
- (IGNORE-ERRORS (MULTIPLE-VALUE-PROG1 (PROGN (THE REAL '(1 2 3)))))
- still returns (1 2 3).
- still-broken parts:
- b. (IGNORE-ERRORS (MULTIPLE-VALUE-PROG1 (PROGN (THE REAL '(1 2 3)))))
- returns (1 2 3). (As above, this shows up when writing regression
- tests for fixed-ness of part a.)
- c. Also in sbcl-0.7.7.9, (IGNORE-ERRORS (THE REAL '(1 2 3))) => (1 2 3).
- d. At the REPL,
- (null (ignore-errors
- (let ((arg1 1)
- (arg2 (identity (the real #(1 2 3)))))
- (if (< arg1 arg2) arg1 arg2))))
- => T
- but putting the same expression inside (DEFUN FOO () ...),
- (FOO) => NIL.
- notes:
- * Actually this entry is probably multiple bugs, as
- Alexey Dejneka commented on sbcl-devel 2002-09-03:)
- I don't think that placing these two bugs in one entry is
- a good idea: they have different explanations. The second
- (min 1 nil) is caused by flushing of unused code--IDENTITY
- can do nothing with it. So it is really bug 122. The first
- (min nil) is due to M-V-PROG1: substituting a continuation
- for the result, it forgets about type assertion. The purpose
- of IDENTITY is to save the restricted continuation from
- inaccurate transformations.
- * Alexey Dejneka pointed out that
- (IGNORE-ERRORS (IDENTITY (THE REAL '(1 2 3))))
- works as it should. Also
- (IGNORE-ERRORS (VALUES (THE REAL '(1 2 3))))
- works as it should. Perhaps this is another case of VALUES type
- intersections behaving in non-useful ways?
-
-199: "hairy FUNCTION types confuse the compiler"
- (reported by APD sbcl-devel 2002-09-15)
- (DEFUN MUR (F)
- (EQ NIL (FUNCALL F)))
-
- (DEFUN FOO (F X)
- (DECLARE (TYPE (AND FUNCTION (SATISFIES MUR)) F))
- (FUNCALL F X))
-
- fails to compile, printing
- failed AVER:
- "(AND (EQ (IR2-CONTINUATION-PRIMITIVE-TYPE 2CONT) FUNCTION-PTYPE) (EQ CHECK T))"
-
- APD further reports that this bug is not present in CMUCL.
-
-201: "Incautious type inference from compound CONS types"
- (reported by APD sbcl-devel 2002-09-17)
+
+ [much later, in 2006-08] in fact it's no longer erroneous to use
+ WITH-SLOTS on structure-classes. However, including :METACLASS
+ STRUCTURE-CLASS in the class definition gives a whole bunch of
+ function redefinition warnings, so we're still not good to close
+ this bug...
+
+ c. (fixed in 0.8.4.23)
+
+201: "Incautious type inference from compound types"
+ a. (reported by APD sbcl-devel 2002-09-17)
(DEFUN FOO (X)
(LET ((Y (CAR (THE (CONS INTEGER *) X))))
(SETF (CAR X) NIL)
(FOO ' (1 . 2)) => "NIL IS INTEGER, Y = 1"
-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.
+ b.
+ * (defun foo (x)
+ (declare (type (array * (4 4)) x))
+ (let ((y x))
+ (setq x (make-array '(4 4)))
+ (adjust-array y '(3 5))
+ (= (array-dimension y 0) (eval `(array-dimension ,y 0)))))
+ FOO
+ * (foo (make-array '(4 4) :adjustable t))
+ NIL
+
+205: "environment issues in cross compiler"
+ (These bugs have no impact on user code, but should be fixed or
+ documented.)
+ a. Macroexpanders introduced with MACROLET are defined in the null
+ lexical environment.
+ b. The body of (EVAL-WHEN (:COMPILE-TOPLEVEL) ...) is evaluated in
+ the null lexical environment.
+ c. The cross-compiler cannot inline functions defined in a non-null
+ lexical environment.
+
+207: "poorly distributed SXHASH results for compound data"
+ SBCL's SXHASH could probably try a little harder. ANSI: "the
+ intent is that an implementation should make a good-faith
+ effort to produce hash-codes that are well distributed
+ within the range of non-negative fixnums". But
+ (let ((hits (make-hash-table)))
+ (dotimes (i 16)
+ (dotimes (j 16)
+ (let* ((ij (cons i j))
+ (newlist (push ij (gethash (sxhash ij) hits))))
+ (when (cdr newlist)
+ (format t "~&collision: ~S~%" newlist))))))
+ reports lots of collisions in sbcl-0.7.8. A stronger MIX function
+ would be an obvious way of fix. Maybe it would be acceptably efficient
+ to redo MIX using a lookup into a 256-entry s-box containing
+ 29-bit pseudorandom numbers?
+
+211: "keywords processing"
+ a. :ALLOW-OTHER-KEYS T should allow a function to receive an odd
+ number of keyword arguments.
+
+212: "Sequence functions and circular arguments"
+ COERCE, MERGE and CONCATENATE go into an infinite loop when given
+ circular arguments; it would be good for the user if they could be
+ given an error instead (ANSI 17.1.1 allows this behaviour on the part
+ of the implementation, as conforming code cannot give non-proper
+ sequences to these functions. MAP also has this problem (and
+ solution), though arguably the convenience of being able to do
+ (MAP 'LIST '+ FOO '#1=(1 . #1#))
+ might be classed as more important (though signalling an error when
+ all of the arguments are circular is probably desireable).
+
+213: "Sequence functions and type checking"
+ b. MAP, when given a type argument that is SUBTYPEP LIST, does not
+ check that it will return a sequence of the given type. Fixing
+ it along the same lines as the others (cf. work done around
+ sbcl-0.7.8.45) is possible, but doing so efficiently didn't look
+ entirely straightforward.
+ c. All of these functions will silently accept a type of the form
+ (CONS INTEGER *)
+ whether or not the return value is of this type. This is
+ probably permitted by ANSI (see "Exceptional Situations" under
+ ANSI MAKE-SEQUENCE), but the DERIVE-TYPE mechanism does not
+ know about this escape clause, so code of the form
+ (INTEGERP (CAR (MAKE-SEQUENCE '(CONS INTEGER *) 2)))
+ can erroneously return T.
+
+215: ":TEST-NOT handling by functions"
+
+ We should verify that our handling of :TEST-NOT and :TEST is consistent
+ for all functions that accept them: that is, signal an error if both
+ are specified.
+
+ Similarly, a compile-time full warning for calls with both would be good.
+
+ We might also consider a compile-time style warning for :TEST-NOT.
+
+216: "debugger confused by frames with invalid number of arguments"
+ In sbcl-0.7.8.51, executing e.g. (VECTOR-PUSH-EXTEND T), BACKTRACE, Q
+ leaves the system confused, enough so that (QUIT) no longer works.
+ It's as though the process of working with the uninitialized slot in
+ the bad VECTOR-PUSH-EXTEND frame causes GC problems, though that may
+ not be the actual problem. (CMU CL 18c doesn't have problems with this.)
+
+ (Can't reproduce on x86 linux as of 1.0.20.22 - MGL)
+
+ This is probably the same bug as 162
+
+237: "Environment arguments to type functions"
+ a. Functions SUBTYPEP, TYPEP, UPGRADED-ARRAY-ELEMENT-TYPE, and
+ UPGRADED-COMPLEX-PART-TYPE now have an optional environment
+ argument, but they ignore it completely. This is almost
+ certainly not correct.
+ b. Also, the compiler's optimizers for TYPEP have not been informed
+ about the new argument; consequently, they will not transform
+ calls of the form (TYPEP 1 'INTEGER NIL), even though this is
+ just as optimizeable as (TYPEP 1 'INTEGER).
+
+242: "WRITE-SEQUENCE suboptimality"
+ (observed from clx performance)
+ In sbcl-0.7.13, WRITE-SEQUENCE of a sequence of type
+ (SIMPLE-ARRAY (UNSIGNED-BYTE 8) (*)) on a stream with element-type
+ (UNSIGNED-BYTE 8) will write to the stream one byte at a time,
+ rather than writing the sequence in one go, leading to severe
+ performance degradation.
+ As of sbcl-0.9.0.36, this is solved for fd-streams, so is less of a
+ problem in practice. (Fully fixing this would require adding a
+ ansi-stream-n-bout slot and associated methods to write a byte
+ sequence to ansi-stream, similar to the existing ansi-stream-sout
+ slot/functions.)
+
+243: "STYLE-WARNING overenthusiasm for unused variables"
+ (observed from clx compilation)
+ In sbcl-0.7.14, in the presence of the macros
+ (DEFMACRO FOO (X) `(BAR ,X))
+ (DEFMACRO BAR (X) (DECLARE (IGNORABLE X)) 'NIL)
+ somewhat surprising style warnings are emitted for
+ (COMPILE NIL '(LAMBDA (Y) (FOO Y))):
+ ; in: LAMBDA (Y)
+ ; (LAMBDA (Y) (FOO Y))
+ ;
+ ; caught STYLE-WARNING:
+ ; The variable Y is defined but never used.
+
+245: bugs in disassembler
+ b. On X86 operand size prefix is not recognized.
+
+251:
+ (defun foo (&key (a :x))
+ (declare (fixnum a))
+ a)
+
+ does not cause a warning. (BTW: old SBCL issued a warning, but for a
+ function, which was never called!)
+
+256:
+ Compiler does not emit warnings for
+
+ a. (lambda () (svref (make-array 8 :adjustable t) 1))
+
+ b. (fixed at some point before 1.0.4.10)
+
+ c. (lambda (x)
+ (declare (optimize (debug 0)))
+ (declare (type vector x))
+ (list (fill-pointer x)
+ (svref x 1)))
+
+257:
+ Complex array type does not have corresponding type specifier.
+
+ This is a problem because the compiler emits optimization notes when
+ you use a non-simple array, and without a type specifier for hairy
+ array types, there's no good way to tell it you're doing it
+ intentionally so that it should shut up and just compile the code.
+
+ Another problem is confusing error message "asserted type ARRAY
+ conflicts with derived type (VALUES SIMPLE-VECTOR &OPTIONAL)" during
+ compiling (LAMBDA (V) (VALUES (SVREF V 0) (VECTOR-POP V))).
+
+ The last problem is that when type assertions are converted to type
+ checks, types are represented with type specifiers, so we could lose
+ complex attribute. (Now this is probably not important, because
+ currently checks for complex arrays seem to be performed by
+ callees.)
+
+259:
+ (compile nil '(lambda () (aref (make-array 0) 0))) compiles without
+ warning. Analogous cases with the index and length being equal and
+ greater than 0 are warned for; the problem here seems to be that the
+ type required for an array reference of this type is (INTEGER 0 (0))
+ which is canonicalized to NIL.
+
+260:
+ a.
+ (let* ((s (gensym))
+ (t1 (specifier-type s)))
+ (eval `(defstruct ,s))
+ (type= t1 (specifier-type s)))
+ => NIL, NIL
+
+ (fixed in 0.8.1.24)
+
+ b. The same for CSUBTYPEP.
+
+262: "yet another bug in inline expansion of local functions"
+ During inline expansion of a local function Python can try to
+ reference optimized away objects (functions, variables, CTRANs from
+ tags and blocks), which later may lead to problems. Some of the
+ cases are worked around by forbidding expansion in such cases, but
+ the better way would be to reimplement inline expansion by copying
+ IR1 structures.
+
+266:
+ David Lichteblau provided (sbcl-devel 2003-06-01) a patch to fix
+ behaviour of streams with element-type (SIGNED-BYTE 8). The patch
+ looks reasonable, if not obviously correct; however, it caused the
+ PPC/Linux port to segfault during warm-init while loading
+ src/pcl/std-class.fasl. A workaround patch was made, but it would
+ be nice to understand why the first patch caused problems, and to
+ fix the cause if possible.
+
+268: "wrong free declaration scope"
+ The following code must signal type error:
+
+ (locally (declare (optimize (safety 3)))
+ (flet ((foo (x &optional (y (car x)))
+ (declare (optimize (safety 0)))
+ (list x y)))
+ (funcall (eval #'foo) 1)))
+
+270:
+ In the following function constraint propagator optimizes nothing:
+
+ (defun foo (x)
+ (declare (integer x))
+ (declare (optimize speed))
+ (typecase x
+ (fixnum "hala")
+ (fixnum "buba")
+ (bignum "hip")
+ (t "zuz")))
+
+273:
+ Compilation of the following two forms causes "X is unbound" error:
+
+ (symbol-macrolet ((x pi))
+ (macrolet ((foo (y) (+ x y)))
+ (declaim (inline bar))
+ (defun bar (z)
+ (* z (foo 4)))))
+ (defun quux (z)
+ (bar z))
+
+ (See (COERCE (CDR X) 'FUNCTION) in IR1-CONVERT-INLINE-LAMBDA.)
+
+274:
+ CLHS says that type declaration of a symbol macro should not affect
+ its expansion, but in SBCL it does. (If you like magic and want to
+ fix it, don't forget to change all uses of MACROEXPAND to
+ MACROEXPAND*.)
+
+275:
+ The following code (taken from CLOCC) takes a lot of time to compile:
+
+ (defun foo (n)
+ (declare (type (integer 0 #.large-constant) n))
+ (expt 1/10 n))
+
+ (fixed in 0.8.2.51, but a test case would be good)
+
+279: type propagation error -- correctly inferred type goes astray?
+ In sbcl-0.8.3 and sbcl-0.8.1.47, the warning
+ The binding of ABS-FOO is a (VALUES (INTEGER 0 0)
+ &OPTIONAL), not a (INTEGER 1 536870911)
+ is emitted when compiling this file:
+ (declaim (ftype (function ((integer 0 #.most-positive-fixnum))
+ (integer #.most-negative-fixnum 0))
+ foo))
+ (defun foo (x)
+ (- x))
+ (defun bar (x)
+ (let* (;; Uncomment this for a type mismatch warning indicating
+ ;; that the type of (FOO X) is correctly understood.
+ #+nil (fs-foo (float-sign (foo x)))
+ ;; Uncomment this for a type mismatch warning
+ ;; indicating that the type of (ABS (FOO X)) is
+ ;; correctly understood.
+ #+nil (fs-abs-foo (float-sign (abs (foo x))))
+ ;; something wrong with this one though
+ (abs-foo (abs (foo x))))
+ (declare (type (integer 1 100) abs-foo))
+ (print abs-foo)))
+
+ (see also bug 117)
+
+283: Thread safety: libc functions
+ There are places that we call unsafe-for-threading libc functions
+ that we should find alternatives for, or put locks around. Known or
+ strongly suspected problems, as of 1.0.3.13: please update this
+ bug instead of creating new ones
+
+284: Thread safety: special variables
+ There are lots of special variables in SBCL, and I feel sure that at
+ least some of them are indicative of potentially thread-unsafe
+ parts of the system. See doc/internals/notes/threading-specials
+
+286: "recursive known functions"
+ Self-call recognition conflicts with known function
+ recognition. Currently cross compiler and target COMPILE do not
+ recognize recursion, and in target compiler it can be disabled. We
+ can always disable it for known functions with RECURSIVE attribute,
+ but there remains a possibility of a function with a
+ (tail)-recursive simplification pass and transforms/VOPs for base
+ cases.
+
+288: fundamental cross-compilation issues (from old UGLINESS file)
+ Using host floating point numbers to represent target floating point
+ numbers, or host characters to represent target characters, is
+ theoretically shaky. (The characters are OK as long as the characters
+ are in the ANSI-guaranteed character set, though, so they aren't a
+ real problem as long as the sources don't need anything but that;
+ the floats are a real problem.)
+
+289: "type checking and source-transforms"
+ a.
+ (block nil (let () (funcall #'+ (eval 'nil) (eval '1) (return :good))))
+ signals type error.
+
+ Our policy is to check argument types at the moment of a call. It
+ disagrees with ANSI, which says that type assertions are put
+ immediately onto argument expressions, but is easier to implement in
+ IR1 and is more compatible to type inference, inline expansion,
+ etc. IR1-transforms automatically keep this policy, but source
+ transforms for associative functions (such as +), being applied
+ during IR1-convertion, do not. It may be tolerable for direct calls
+ (+ x y z), but for (FUNCALL #'+ x y z) it is non-conformant.
+
+ b. Another aspect of this problem is efficiency. [x y + z +]
+ requires less registers than [x y z + +]. This transformation is
+ currently performed with source transforms, but it would be good to
+ also perform it in IR1 optimization phase.
+
+290: Alpha floating point and denormalized traps
+ In SBCL 0.8.3.6x on the alpha, we work around what appears to be a
+ hardware or kernel deficiency: the status of the enable/disable
+ denormalized-float traps bit seems to be ambiguous; by the time we
+ get to os_restore_fp_control after a trap, denormalized traps seem
+ to be enabled. Since we don't want a trap every time someone uses a
+ denormalized float, in general, we mask out that bit when we restore
+ the control word; however, this clobbers any change the user might
+ have made.
+
+297:
+ LOOP with non-constant arithmetic step clauses suffers from overzealous
+ type constraint: code of the form
+ (loop for d of-type double-float from 0d0 to 10d0 by x collect d)
+ compiles to a type restriction on X of (AND DOUBLE-FLOAT (REAL
+ (0))). However, an integral value of X should be legal, because
+ successive adds of integers to double-floats produces double-floats,
+ so none of the type restrictions in the code is violated.
+
+300: (reported by Peter Graves) Function PEEK-CHAR checks PEEK-TYPE
+ argument type only after having read a character. This is caused
+ with EXPLICIT-CHECK attribute in DEFKNOWN. The similar problem
+ exists with =, /=, <, >, <=, >=. They were fixed, but it is probably
+ less error prone to have EXPLICIT-CHECK be a local declaration,
+ being put into the definition, instead of an attribute being kept in
+ a separate file; maybe also put it into SB-EXT?
+
+301: ARRAY-SIMPLE-=-TYPE-METHOD breaks on corner cases which can arise
+ in NOTE-ASSUMED-TYPES
+ In sbcl-0.8.7.32, compiling the file
+ (defun foo (x y)
+ (declare (type integer x))
+ (declare (type (vector (or hash-table bit)) y))
+ (bletch 2 y))
+ (defun bar (x y)
+ (declare (type integer x))
+ (declare (type (simple-array base (2)) y))
+ (bletch 1 y))
+ gives the error
+ failed AVER: "(NOT (AND (NOT EQUALP) CERTAINP))"
+
+303: "nonlinear LVARs" (aka MISC.293)
+ (defun buu (x)
+ (multiple-value-call #'list
+ (block foo
+ (multiple-value-prog1
+ (eval '(values :a :b :c))
+ (catch 'bar
+ (if (> x 0)
+ (return-from foo
+ (eval `(if (> ,x 1)
+ 1
+ (throw 'bar (values 3 4)))))))))))
+
+ (BUU 1) returns garbage.
+
+ The problem is that both EVALs sequentially write to the same LVAR.
+
+306: "Imprecise unions of array types"
+
+ a. fixed in SBCL 0.9.15.48
+
+ b.(subtypep
+ 'array
+ `(or
+ ,@(loop for x across sb-vm:*specialized-array-element-type-properties*
+ collect `(array ,(sb-vm:saetp-specifier x)))))
+ => NIL, T (when it should be T, T)
+
+309: "Dubious values for implementation limits"
+ (reported by Bruno Haible sbcl-devel "Incorrect value of
+ multiple-values-limit" 2004-04-19)
+ (values-list (make-list 1000000)), on x86/linux, signals a stack
+ exhaustion condition, despite MULTIPLE-VALUES-LIMIT being
+ significantly larger than 1000000. There are probably similar
+ dubious values for CALL-ARGUMENTS-LIMIT (see cmucl-help/cmucl-imp
+ around the same time regarding a call to LIST on sparc with 1000
+ arguments) and other implementation limit constants.
+
+314: "LOOP :INITIALLY clauses and scope of initializers"
+ reported by Bruno Haible sbcl-devel "various SBCL bugs" from CLISP
+ test suite, originally by Thomas F. Burdick.
+ ;; <http://www.lisp.org/HyperSpec/Body/sec_6-1-7-2.html>
+ ;; According to the HyperSpec 6.1.2.1.4, in for-as-equals-then, var is
+ ;; initialized to the result of evaluating form1. 6.1.7.2 says that
+ ;; initially clauses are evaluated in the loop prologue, which precedes all
+ ;; loop code except for the initial settings provided by with, for, or as.
+ (loop :for x = 0 :then (1+ x)
+ :for y = (1+ x) :then (ash y 1)
+ :for z :across #(1 3 9 27 81 243)
+ :for w = (+ x y z)
+ :initially (assert (zerop x)) :initially (assert (= 2 w))
+ :until (>= w 100) :collect w)
+ Expected: (2 6 15 38)
+ Got: ERROR
+
+318: "stack overflow in compiler warning with redefined class"
+ reported by Bruno Haible sbcl-devel "various SBCL bugs" from CLISP
+ test suite.
+ (defstruct foo a)
+ (setf (find-class 'foo) nil)
+ (defstruct foo slot-1)
+ This used to give a stack overflow from within the printer, which has
+ been fixed as of 0.8.16.11. Current result:
+ ; caught ERROR:
+ ; can't compile TYPEP of anonymous or undefined class:
+ ; #<SB-KERNEL:STRUCTURE-CLASSOID FOO>
+ ...
+ debugger invoked on a TYPE-ERROR in thread 19973:
+ The value NIL is not of type FUNCTION.
+
+ CSR notes: it's not really clear what it should give: is (SETF FIND-CLASS)
+ meant to be enough to delete structure classes from the system?
+
+319: "backquote with comma inside array"
+ reported by Bruno Haible sbcl-devel "various SBCL bugs" from CLISP
+ test suite.
+ (read-from-string "`#1A(1 2 ,(+ 2 2) 4)")
+ gives
+ #(1 2 ((SB-IMPL::|,|) + 2 2) 4)
+ which probably isn't intentional.
+
+324: "STREAMs and :ELEMENT-TYPE with large bytesize"
+ In theory, (open foo :element-type '(unsigned-byte <x>)) should work
+ for all positive integral <x>. At present, it only works for <x> up
+ to about 1024 (and similarly for signed-byte), so
+ (open "/dev/zero" :element-type '(unsigned-byte 1025))
+ gives an error in sbcl-0.8.10.
+
+325: "CLOSE :ABORT T on superseding streams"
+ Closing a stream opened with :IF-EXISTS :SUPERSEDE with :ABORT T leaves no
+ file on disk, even if one existed before opening.
+
+ The illegality of this is not crystal clear, as the ANSI dictionary
+ entry for CLOSE says that when :ABORT is T superseded files are not
+ superseded (ie. the original should be restored), whereas the OPEN
+ entry says about :IF-EXISTS :SUPERSEDE "If possible, the
+ implementation should not destroy the old file until the new stream
+ is closed." -- implying that even though undesirable, early deletion
+ is legal. Restoring the original would none the less be the polite
+ thing to do.
+
+326: "*PRINT-CIRCLE* crosstalk between streams"
+ In sbcl-0.8.10.48 it's possible for *PRINT-CIRCLE* references to be
+ mixed between streams when output operations are intermingled closely
+ enough (as by doing output on S2 from within (PRINT-OBJECT X S1) in the
+ test case below), so that e.g. the references #2# appears on a stream
+ with no preceding #2= on that stream to define it (because the #2= was
+ sent to another stream).
+ (cl:in-package :cl-user)
+ (defstruct foo index)
+ (defparameter *foo* (make-foo :index 4))
+ (defstruct bar)
+ (defparameter *bar* (make-bar))
+ (defparameter *tangle* (list *foo* *bar* *foo*))
+ (defmethod print-object ((foo foo) stream)
+ (let ((index (foo-index foo)))
+ (format *trace-output*
+ "~&-$- emitting FOO ~D, ambient *BAR*=~S~%"
+ index *bar*)
+ (format stream "[FOO ~D]" index))
+ foo)
+ (let ((tsos (make-string-output-stream))
+ (ssos (make-string-output-stream)))
+ (let ((*print-circle* t)
+ (*trace-output* tsos)
+ (*standard-output* ssos))
+ (prin1 *tangle* *standard-output*))
+ (let ((string (get-output-stream-string ssos)))
+ (unless (string= string "(#1=[FOO 4] #S(BAR) #1#)")
+ ;; In sbcl-0.8.10.48 STRING was "(#1=[FOO 4] #2# #1#)".:-(
+ (error "oops: ~S" string)))))
+ It might be straightforward to fix this by turning the
+ *CIRCULARITY-HASH-TABLE* and *CIRCULARITY-COUNTER* variables into
+ per-stream slots, but (1) it would probably be sort of messy faking
+ up the special variable binding semantics using UNWIND-PROTECT and
+ (2) it might be sort of a pain to test that no other bugs had been
+ introduced.
+
+328: "Profiling generic functions", transplanted from #241
+ (from tonyms on #lisp IRC 2003-02-25)
+ In sbcl-0.7.12.55, typing
+ (defclass foo () ((bar :accessor foo-bar)))
+ (profile foo-bar)
+ (unintern 'foo-bar)
+ (defclass foo () ((bar :accessor foo-bar)))
+ gives the error message
+ "#:FOO-BAR already names an ordinary function or a macro."
+
+ Problem: when a generic function is profiled, it appears as an ordinary
+ function to PCL. (Remembering the uninterned accessor is OK, as the
+ redefinition must be able to remove old accessors from their generic
+ functions.)
+
+329: "Sequential class redefinition"
+ reported by Bruno Haible:
+ (defclass reactor () ((max-temp :initform 10000000)))
+ (defvar *r1* (make-instance 'reactor))
+ (defvar *r2* (make-instance 'reactor))
+ (slot-value *r1* 'max-temp)
+ (slot-value *r2* 'max-temp)
+ (defclass reactor () ((uptime :initform 0)))
+ (slot-value *r1* 'uptime)
+ (defclass reactor () ((uptime :initform 0) (max-temp :initform 10000)))
+ (slot-value *r1* 'max-temp) ; => 10000
+ (slot-value *r2* 'max-temp) ; => 10000000 oops...
+
+ Possible solution:
+ The method effective when the wrapper is obsoleted can be saved
+ in the wrapper, and then to update the instance just run through
+ all the old wrappers in order from oldest to newest.
+
+336: "slot-definitions must retain the generic functions of accessors"
+ reported by Tony Martinez:
+ (defclass foo () ((bar :reader foo-bar)))
+ (defun foo-bar (x) x)
+ (defclass foo () ((bar :reader get-bar))) ; => error, should work
+
+ Note: just punting the accessor removal if the fdefinition
+ is not a generic function is not enough:
+
+ (defclass foo () ((bar :reader foo-bar)))
+ (defvar *reader* #'foo-bar)
+ (defun foo-bar (x) x)
+ (defclass foo () ((bar :initform 'ok :reader get-bar)))
+ (funcall *reader* (make-instance 'foo)) ; should be an error, since
+ ; the method must be removed
+ ; by the class redefinition
+
+ Fixing this should also fix a subset of #328 -- update the
+ description with a new test-case then.
+
+339: "DEFINE-METHOD-COMBINATION bugs"
+ (reported by Bruno Haible via the clisp test suite)
+
+ a. Syntax checking laxity (should produce errors):
+ i. (define-method-combination foo :documentation :operator)
+ ii. (define-method-combination foo :documentation nil)
+ iii. (define-method-combination foo nil)
+ iv. (define-method-combination foo nil nil
+ (:arguments order &aux &key))
+ v. (define-method-combination foo nil nil (:arguments &whole))
+ vi. (define-method-combination foo nil nil (:generic-function))
+ vii. (define-method-combination foo nil nil (:generic-function bar baz))
+ viii. (define-method-combination foo nil nil (:generic-function (bar)))
+ ix. (define-method-combination foo nil ((3)))
+ x. (define-method-combination foo nil ((a)))
+
+ b. define-method-combination arguments lambda list badness
+ i. &aux args are currently unsupported;
+ ii. default values of &optional and &key arguments are ignored;
+ iii. supplied-p variables for &optional and &key arguments are not
+ bound.
+
+ c. (fixed in sbcl-0.9.15.15)
+
+344: more (?) ROOM T problems (possibly part of bug 108)
+ In sbcl-0.8.12.51, and off and on leading up to it, the
+ SB!VM:MEMORY-USAGE operations in ROOM T caused
+ unhandled condition (of type SB-INT:BUG):
+ failed AVER: "(SAP= CURRENT END)"
+ Several clever people have taken a shot at this without fixing
+ it; this time around (before sbcl-0.8.13 release) I (WHN) just
+ commented out the SB!VM:MEMORY-USAGE calls until someone figures
+ out how to make them work reliably with the rest of the GC.
+
+ (Note: there's at least one dubious thing in room.lisp: see the
+ comment in VALID-OBJ)
+
+346: alpha backtrace
+ In sbcl-0.8.13, all backtraces from errors caused by internal errors
+ on the alpha seem to have a "bogus stack frame".
+
+349: PPRINT-INDENT rounding implementation decisions
+ At present, pprint-indent (and indeed the whole pretty printer)
+ more-or-less assumes that it's using a monospace font. That's
+ probably not too silly an assumption, but one piece of information
+ the current implementation loses is from requests to indent by a
+ non-integral amount. As of sbcl-0.8.15.9, the system silently
+ truncates the indentation to an integer at the point of request, but
+ maybe the non-integral value should be propagated through the
+ pprinter and only truncated at output? (So that indenting by 1/2
+ then 3/2 would indent by two spaces, not one?)
+
+352: forward-referenced-class trouble
+ reported by Bruno Haible on sbcl-devel
+ (defclass c (a) ())
+ (setf (class-name (find-class 'a)) 'b)
+ (defclass a () (x))
+ (defclass b () (y))
+ (make-instance 'c)
+ Expected: an instance of c, with a slot named x
+ Got: debugger invoked on a SIMPLE-ERROR in thread 78906:
+ While computing the class precedence list of the class named C.
+ The class named B is a forward referenced class.
+ The class named B is a direct superclass of the class named C.
+
+ [ Is this actually a bug? DEFCLASS only replaces an existing class
+ when the class name is the proper name of that class, and in the
+ above code the class found by (FIND-CLASS 'A) does not have a
+ proper name. CSR, 2006-08-07 ]
+
+353: debugger suboptimalities on x86
+ On x86 backtraces for undefined functions start with a bogus stack
+ frame, and backtraces for throws to unknown catch tags with a "no
+ debug information" frame. These are both due to CODE-COMPONENT-FROM-BITS
+ (used on non-x86 platforms) being a more complete solution then what
+ is done on x86.
+
+ On x86/linux large portions of tests/debug.impure.lisp have been commented
+ out as failures. The probable culprit for these problems is in x86-call-context
+ (things work fine on x86/freebsd).
+
+ More generally, the debugger internals suffer from excessive x86/non-x86
+ conditionalization and OAOOMization: refactoring the common parts would
+ be good.
+
+356: PCL corruption
+ (reported by Bruno Haible)
+ After the "layout depth conflict" error, the CLOS is left in a state where
+ it's not possible to define new standard-class subclasses any more.
+ Test case:
+ (defclass prioritized-dispatcher ()
+ ((dependents :type list :initform nil)))
+ (defmethod sb-pcl:validate-superclass ((c1 sb-pcl:funcallable-standard-class)
+ (c2 (eql (find-class 'prioritized-dispatcher))))
+ t)
+ (defclass prioritized-generic-function (prioritized-dispatcher standard-generic-function)
+ ()
+ (:metaclass sb-pcl:funcallable-standard-class))
+ ;; ERROR, Quit the debugger with ABORT
+ (defclass typechecking-reader-class (standard-class)
+ ())
+ Expected: #<STANDARD-CLASS TYPECHECKING-READER-CLASS>
+ Got: ERROR "The assertion SB-PCL::WRAPPERS failed."
+
+ [ This test case does not cause the error any more. However,
+ similar problems can be observed with
+
+ (defclass foo (standard-class) ()
+ (:metaclass sb-mop:funcallable-standard-class))
+ (sb-mop:finalize-inheritance (find-class 'foo))
+ ;; ERROR, ABORT
+ (defclass bar (standard-class) ())
+ (make-instance 'bar)
+ ]
+
+359: wrong default value for ensure-generic-function's :generic-function-class argument
+ (reported by Bruno Haible)
+ ANSI CL is silent on this, but the MOP's specification of ENSURE-GENERIC-FUNCTION says:
+ "The remaining arguments are the complete set of keyword arguments
+ received by ENSURE-GENERIC-FUNCTION."
+ and the spec of ENSURE-GENERIC-FUNCTION-USING-CLASS:
+ ":GENERIC-FUNCTION-CLASS - a class metaobject or a class name. If it is not
+ supplied, it defaults to the class named STANDARD-GENERIC-FUNCTION."
+ This is not the case in SBCL. Test case:
+ (defclass my-generic-function (standard-generic-function)
+ ()
+ (:metaclass sb-pcl:funcallable-standard-class))
+ (setf (fdefinition 'foo1)
+ (make-instance 'my-generic-function :name 'foo1))
+ (ensure-generic-function 'foo1
+ :generic-function-class (find-class 'standard-generic-function))
+ (class-of #'foo1)
+ ; => #<SB-MOP:FUNCALLABLE-STANDARD-CLASS STANDARD-GENERIC-FUNCTION>
+ (setf (fdefinition 'foo2)
+ (make-instance 'my-generic-function :name 'foo2))
+ (ensure-generic-function 'foo2)
+ (class-of #'foo2)
+ Expected: #<SB-MOP:FUNCALLABLE-STANDARD-CLASS STANDARD-GENERIC-FUNCTION>
+ Got: #<SB-MOP:FUNCALLABLE-STANDARD-CLASS MY-GENERIC-FUNCTION>
+
+362: missing error when a slot-definition is created without a name
+ (reported by Bruno Haible)
+ The MOP says about slot-definition initialization:
+ "The :NAME argument is a slot name. An ERROR is SIGNALled if this argument
+ is not a symbol which can be used as a variable name. An ERROR is SIGNALled
+ if this argument is not supplied."
+ Test case:
+ (make-instance (find-class 'sb-pcl:standard-direct-slot-definition))
+ Expected: ERROR
+ Got: #<SB-MOP:STANDARD-DIRECT-SLOT-DEFINITION NIL>
+
+363: missing error when a slot-definition is created with a wrong documentation object
+ (reported by Bruno Haible)
+ The MOP says about slot-definition initialization:
+ "The :DOCUMENTATION argument is a STRING or NIL. An ERROR is SIGNALled
+ if it is not. This argument default to NIL during initialization."
+ Test case:
+ (make-instance (find-class 'sb-pcl:standard-direct-slot-definition)
+ :name 'foo
+ :documentation 'not-a-string)
+ Expected: ERROR
+ Got: #<SB-MOP:STANDARD-DIRECT-SLOT-DEFINITION FOO>
+
+370: reader misbehaviour on large-exponent floats
+ (read-from-string "1.0s1000000000000000000000000000000000000000")
+ causes the reader to attempt to create a very large bignum (which it
+ will then attempt to coerce to a rational). While this isn't
+ completely wrong, it is probably not ideal -- checking the floating
+ point control word state and then returning the relevant float
+ (most-positive-short-float or short-float-infinity) or signalling an
+ error immediately would seem to make more sense.
+
+372: floating-point overflow not signalled on ppc/darwin
+ The following assertions in float.pure.lisp fail on ppc/darwin
+ (Mac OS X version 10.3.7):
+ (assert (raises-error? (scale-float 1.0 most-positive-fixnum)
+ floating-point-overflow))
+ (assert (raises-error? (scale-float 1.0d0 (1+ most-positive-fixnum))
+ floating-point-overflow)))
+ as the SCALE-FLOAT just returns
+ #.SB-EXT:SINGLE/DOUBLE-FLOAT-POSITIVE-INFINITY. These tests have been
+ disabled on Darwin for now.
+
+377: Memory fault error reporting
+ On those architectures where :C-STACK-IS-CONTROL-STACK is in
+ *FEATURES*, we handle SIG_MEMORY_FAULT (SEGV or BUS) on an altstack,
+ so we cannot handle the signal directly (as in interrupt_handle_now())
+ in the case when the signal comes from some external agent (the user
+ using kill(1), or a fault in some foreign code, for instance). As
+ of sbcl-0.8.20.20, this is fixed by calling
+ arrange_return_to_lisp_function() to a new error-signalling
+ function, but as a result the error reporting is poor: we cannot
+ even tell the user at which address the fault occurred. We should
+ arrange such that arguments can be passed to the function called from
+ arrange_return_to_lisp_function(), but this looked hard to do in
+ general without suffering from memory leaks.
+
+379: TRACE :ENCAPSULATE NIL broken on ppc/darwin
+ See commented-out test-case in debug.impure.lisp.
+
+382: externalization unexpectedly changes array simplicity
+ COMPILE-FILE and LOAD
+ (defun foo ()
+ (let ((x #.(make-array 4 :fill-pointer 0)))
+ (values (eval `(typep ',x 'simple-array))
+ (typep x 'simple-array))))
+ then (FOO) => T, NIL.
+
+ Similar problems exist with SIMPLE-ARRAY-P, ARRAY-HEADER accessors
+ and all array dimension functions.
+
+383: ASH'ing non-constant zeros
+ Compiling
+ (lambda (b)
+ (declare (type (integer -2 14) b))
+ (declare (ignorable b))
+ (ash (imagpart b) 57))
+ on PPC (and other platforms, presumably) gives an error during the
+ emission of FASH-ASH-LEFT/FIXNUM=>FIXNUM as the assembler attempts to
+ stuff a too-large constant into the immediate field of a PPC
+ instruction. Either the VOP should be fixed or the compiler should be
+ taught how to transform this case away, paying particular attention
+ to side-effects that might occur in the arguments to ASH.
+
+384: Compiler runaway on very large character types
+
+ (compile nil '(lambda (x)
+ (declare (type (member #\a 1) x))
+ (the (member 1 nil) x)))
+
+ The types apparently normalize into a very large type, and the compiler
+ gets lost in REMOVE-DUPLICATES. Perhaps the latter should use
+ a better algorithm (one based on hash tables, say) on very long lists
+ when :TEST has its default value?
+
+ A simpler example:
+
+ (compile nil '(lambda (x) (the (not (eql #\a)) x)))
+
+ (partially fixed in 0.9.3.1, but a better representation for these
+ types is needed.)
+
+385:
+ (format nil "~4,1F" 0.001) => "0.00" (should be " 0.0");
+ (format nil "~4,1@F" 0.001) => "+.00" (should be "+0.0").
+ (format nil "~E" 0.01) => "10.e-3" (should be "1.e-2");
+ (format nil "~G" 0.01) => "10.e-3" (should be "1.e-2");
+
+386: SunOS/x86 stack exhaustion handling broken
+ According to <http://alfa.s145.xrea.com/sbcl/solaris-x86.html>, the
+ stack exhaustion checking (implemented with a write-protected guard
+ page) does not work on SunOS/x86.
+
+388:
+ (found by Dmitry Bogomolov)
+
+ (defclass foo () ((x :type (unsigned-byte 8))))
+ (defclass bar () ((x :type symbol)))
+ (defclass baz (foo bar) ())
+
+ causes error
+
+ SB-PCL::SPECIALIZER-APPLICABLE-USING-TYPE-P cannot handle the second argument
+ (UNSIGNED-BYTE 8).
+
+ [ Can't trigger this any more, as of 2006-08-07 ]
+
+389:
+ (reported several times on sbcl-devel, by Rick Taube, Brian Rowe and
+ others)
+
+ ROUND-NUMERIC-BOUND assumes that float types always have a FORMAT
+ specifying whether they're SINGLE or DOUBLE. This is true for types
+ computed by the type system itself, but the compiler type derivation
+ short-circuits this and constructs non-canonical types. A temporary
+ fix was made to ROUND-NUMERIC-BOUND for the sbcl-0.9.6 release, but
+ the right fix is to remove the abstraction violation in the
+ compiler's type deriver.
+
+393: Wrong error from methodless generic function
+ (DEFGENERIC FOO (X))
+ (FOO 1 2)
+ gives NO-APPLICABLE-METHOD rather than an argument count error.
+
+396: block-compilation bug
+ (let ((x 1))
+ (dotimes (y 10)
+ (let ((y y))
+ (when (funcall (eval #'(lambda (x) (eql x 2))) y)
+ (defun foo (z)
+ (incf x (incf y z))))))
+ (defun bar (z)
+ (foo z)
+ (values x)))
+ (bar 1) => 11, should be 4.
+
+397: SLEEP accuracy
+ The more interrupts arrive the less accurate SLEEP's timing gets.
+ (time (sb-thread:terminate-thread
+ (prog1 (sb-thread:make-thread (lambda ()
+ (loop
+ (princ #\!)
+ (force-output)
+ (sb-ext:gc))))
+ (sleep 1))))
+
+398: GC-unsafe SB-ALIEN string deporting
+ Translating a Lisp string to an alien string by taking a SAP to it
+ as done by the :DEPORT-GEN methods for C-STRING and UTF8-STRING
+ is not safe, since the Lisp string can move. For example the
+ following code will fail quickly on both cheneygc and pre-0.9.8.19
+ GENCGC:
+
+ (setf (bytes-consed-between-gcs) 4096)
+ (define-alien-routine "strcmp" int (s1 c-string) (s2 c-string))
+
+ (loop
+ (let ((string "hello, world"))
+ (assert (zerop (strcmp string string)))))
+
+ (This will appear to work on post-0.9.8.19 GENCGC, since
+ the GC no longer zeroes memory immediately after releasing
+ it after a minor GC. Either enabling the READ_PROTECT_FREE_PAGES
+ #define in gencgc.c or modifying the example so that a major
+ GC will occasionally be triggered would unmask the bug.)
+
+ On cheneygc the only solution would seem to be allocating some alien
+ memory, copying the data over, and arranging that it's freed once we
+ return. For GENCGC we could instead try to arrange that the string
+ from which the SAP is taken is always pinned.
+
+ For some more details see comments for (define-alien-type-method
+ (c-string :deport-gen) ...) in host-c-call.lisp.
+
+403: FORMAT/PPRINT-LOGICAL-BLOCK of CONDITIONs ignoring *PRINT-CIRCLE*
+ In sbcl-0.9.13.34,
+ (defparameter *c*
+ (make-condition 'simple-error
+ :format-control "ow... ~S"
+ :format-arguments '(#1=(#1#))))
+ (setf *print-circle* t *print-level* 4)
+ (format nil "~@<~A~:@>" *c*)
+ gives
+ "ow... (((#)))"
+ where I (WHN) believe the correct result is "ow... #1=(#1#)",
+ like the result from (PRINC-TO-STRING *C*). The question of
+ what the correct result is is complicated by the hairy text in
+ the Hyperspec "22.3.5.2 Tilde Less-Than-Sign: Logical Block",
+ Other than the difference in its argument, ~@<...~:> is
+ exactly the same as ~<...~:> except that circularity detection
+ is not applied if ~@<...~:> is encountered at top level in a
+ format string.
+ But because the odd behavior happens even without the at-sign,
+ (format nil "~<~A~:@>" (list *c*)) ; => "ow... (((#)))"
+ and because something seemingly similar can happen even in
+ PPRINT-LOGICAL-BLOCK invoked directly without FORMAT,
+ (pprint-logical-block (*standard-output* '(some nonempty list))
+ (format *standard-output* "~A" '#1=(#1#)))
+ (which prints "(((#)))" to *STANDARD-OUTPUT*), I don't think
+ that the 22.3.5.2 trickiness is fundamental to the problem.
+
+ My guess is that the problem is related to the logic around the MODE
+ argument to CHECK-FOR-CIRCULARITY, but I haven't reverse-engineered
+ enough of the intended meaning of the different MODE values to be
+ confident of this.
+
+404: nonstandard DWIMness in LOOP with unportably-ordered clauses
+ In sbcl-0.9.13, the code
+ (loop with stack = (make-array 2 :fill-pointer 2 :initial-element t)
+ for length = (length stack)
+ while (plusp length)
+ for element = (vector-pop stack)
+ collect element)
+ compiles without error or warning and returns (T T). Unfortunately,
+ it is inconsistent with the ANSI definition of the LOOP macro,
+ because it mixes up VARIABLE-CLAUSEs with MAIN-CLAUSEs. Furthermore,
+ SBCL's interpretation of the intended meaning is only one possible,
+ unportable interpretation of the noncompliant code; in CLISP 2.33.2,
+ the code compiles with a warning
+ LOOP: FOR clauses should occur before the loop's main body
+ and then fails at runtime with
+ VECTOR-POP: #() has length zero
+ perhaps because CLISP has shuffled the clauses into an
+ ANSI-compliant order before proceeding.
+
+406: functional has external references -- failed aver
+ Given the following food in a single file
+ (eval-when (:compile-toplevel :load-toplevel :execute)
+ (defstruct foo3))
+ (defstruct bar
+ (foo #.(make-foo3)))
+ as of 0.9.18.11 the file compiler breaks on it:
+ failed AVER: "(NOT (FUNCTIONAL-HAS-EXTERNAL-REFERENCES-P CLAMBDA))"
+ Defining the missing MAKE-LOAD-FORM method makes the error go away.
+
+407: misoptimization of loop, COERCE 'FLOAT, and HANDLER-CASE for bignums
+ (reported by Ariel Badichi on sbcl-devel 2007-01-09)
+ 407a: In sbcl-1.0.1 on Linux x86,
+ (defun foo ()
+ (loop for n from (expt 2 1024) do
+ (handler-case
+ (coerce n 'single-float)
+ (simple-type-error ()
+ (format t "Got here.~%")
+ (return-from foo)))))
+ (foo)
+ causes an infinite loop, where handling the error would be expected.
+ 407b: In sbcl-1.0.1 on Linux x86,
+ (defun bar ()
+ (loop for n from (expt 2 1024) do
+ (handler-case
+ (format t "~E~%" (coerce n 'single-float))
+ (simple-type-error ()
+ (format t "Got here.~%")
+ (return-from bar)))))
+ fails to compile, with
+ Too large to be represented as a SINGLE-FLOAT: ...
+ from
+ 0: ((LABELS SB-BIGNUM::CHECK-EXPONENT) ...)
+ 1: ((LABELS SB-BIGNUM::FLOAT-FROM-BITS) ...)
+ 2: (SB-KERNEL:%SINGLE-FLOAT ...)
+ 3: (SB-C::BOUND-FUNC ...)
+ 4: (SB-C::%SINGLE-FLOAT-DERIVE-TYPE-AUX ...)
+
+ These are now fixed, but (COERCE HUGE 'SINGLE-FLOAT) still signals a
+ type-error at runtime. The question is, should it instead signal a
+ floating-point overflow, or return an infinity?
+
+408: SUBTYPEP confusion re. OR of SATISFIES of not-yet-defined predicate
+ As reported by Levente M\'{e}sz\'{a}ros sbcl-devel 2006-02-20,
+ (aver (equal (multiple-value-list
+ (subtypep '(or (satisfies x) string)
+ '(or (satisfies x) integer)))
+ '(nil nil)))
+ fails. Also, beneath that failure lurks another failure,
+ (aver (equal (multiple-value-list
+ (subtypep 'string
+ '(or (satisfies x) integer)))
+ '(nil nil)))
+ Having looked at this for an hour or so in sbcl-1.0.2, and
+ specifically having looked at the output from
+ laptop$ sbcl
+ * (let ((x 'string)
+ (y '(or (satisfies x) integer)))
+ (trace sb-kernel::union-complex-subtypep-arg2
+ sb-kernel::invoke-complex-subtypep-arg1-method
+ sb-kernel::type-union
+ sb-kernel::type-intersection
+ sb-kernel::type=)
+ (subtypep x y))
+ my (WHN) impression is that the problem is that the semantics of TYPE=
+ are wrong for what the UNION-COMPLEX-SUBTYPEP-ARG2 code is trying
+ to use it for. The comments on the definition of TYPE= probably
+ date back to CMU CL and seem to define it as a confusing thing:
+ its primary value is something like "certainly equal," and its
+ secondary value is something like "certain about that certainty."
+ I'm left uncertain how to fix UNION-COMPLEX-SUBTYPEP-ARG2 without
+ reducing its generality by removing the TYPE= cleverness. Possibly
+ the tempting TYPE/= relative defined next to it might be a
+ suitable replacement for the purpose. Probably, though, it would
+ be best to start by reverse engineering exactly what TYPE= and
+ TYPE/= do, and writing an explanation which is so clear that one
+ can see immediately what it's supposed to mean in odd cases like
+ (TYPE= '(SATISFIES X) 'INTEGER) when X isn't defined yet.
+
+409: MORE TYPE SYSTEM PROBLEMS
+ Found while investigating an optimization failure for extended
+ sequences. The extended sequence type implementation was altered to
+ work around the problem, but the fundamental problem remains, to wit:
+ (sb-kernel:type= (sb-kernel:specifier-type '(or float ratio))
+ (sb-kernel:specifier-type 'single-float))
+ returns NIL, NIL on sbcl-1.0.3.
+ (probably related to bug #408)
+
+410: read circularities and type declarations
+ Consider the definition
+ (defstruct foo (a 0 :type (not symbol)))
+ followed by
+ (setf *print-circle* t) ; just in case
+ (read-from-string "#1=#s(foo :a #1#)")
+ This gives a type error (#:G1 is not a (NOT SYMBOL)) because of the
+ implementation of read circularity, using a symbol as a marker for
+ the previously-referenced object.
+
+416: backtrace confusion
+
+ (defun foo (x)
+ (let ((v "foo"))
+ (flet ((bar (z)
+ (oops v z)
+ (oops z v)))
+ (bar x)
+ (bar v))))
+ (foo 13)
+
+ gives the correct error, but the backtrace shows
+ 1: (SB-KERNEL:FDEFINITION-OBJECT 13 NIL)
+ as the second frame.
+
+418: SUBSEQ on lists doesn't support bignum indexes
+
+ LIST-SUBSEQ* now has all the works necessary to support bignum indexes,
+ but it needs to be verified that changing the DEFKNOWN doesn't kill
+ performance elsewhere.
+
+ Other generic sequence functions have this problem as well.
+
+419: stack-allocated indirect closure variables are not popped
+
+ (defun bug419 (x)
+ (multiple-value-call #'list
+ (eval '(values 1 2 3))
+ (let ((x x))
+ (declare (sb-int:truly-dynamic-extent x))
+ (flet ((mget (y)
+ (+ x y))
+ (mset (z)
+ (incf x z)))
+ (declare (dynamic-extent #'mget #'mset))
+ ((lambda (f g) (eval `(progn ,f ,g (values 4 5 6)))) #'mget #'mset)))))
+
+ (ASSERT (EQUAL (BUG419 42) '(1 2 3 4 5 6))) => failure
+
+ Note: as of SBCL 1.0.16.29 this bug no longer affects user code, as
+ SB-INT:TRULY-DYNAMIC-EXTENT needs to be used instead of
+ DYNAMIC-EXTENT for this to happen. Proper fix for this bug requires
+ (Nikodemus thinks) storing the relevant LAMBDA-VARs in a
+ :DYNAMIC-EXTENT cleanup, and teaching stack analysis how to deal
+ with them.
+
+421: READ-CHAR-NO-HANG misbehaviour on Windows Console:
+
+ It seems that on Windows READ-CHAR-NO-HANG hangs if the user
+ has pressed a key, but not yet enter (ie. SYSREAD-MAY-BLOCK-P
+ seems to lie if the OS is buffering input for us on Console.)
+
+ reported by Elliot Slaughter on sbcl-devel 2008/1/10.
+
+422: out-of-extent return not checked in safe code
+
+ (declaim (optimize safety))
+ (funcall (catch 't (block nil (throw 't (lambda () (return))))))
+
+behaves ...erratically. Reported by Kevin Reid on sbcl-devel
+2007-07-06. (We don't _have_ to check things like this, but we
+generally try to check returns in safe code, so we should here too.)
+
+424: toplevel closures and *CHECK-CONSISTENCY*
+
+ The following breaks under COMPILE-FILE if *CHECK-CONSISTENCY* is true.
+
+ (let ((exported-symbols-alist
+ (loop for symbol being the external-symbols of :cl
+ collect (cons symbol
+ (concatenate 'string
+ "#"
+ (string-downcase symbol))))))
+ (defun hyperdoc-lookup (symbol)
+ (cdr (assoc symbol exported-symbols-alist))))
+
+ (Test-case adapted from CL-PPCRE.)
+
+428: TIMER SCHEDULE-STRESS and PARALLEL-UNSCHEDULE in
+ timer.impure.lisp fails
+
+ Failure modes vary. Core problem seems to be (?) recursive entry to
+ RUN-EXPIRED-TIMERS.
+
+429: compiler hangs
+
+ Compiling a file with this contents makes the compiler loop in
+ ORDER-UVL-SETS:
+
+ (declaim (inline storage))
+ (defun storage (x)
+ (the (simple-array flt (*)) (unknown x)))
+
+ (defun test1 (lumps &key cg)
+ (let ((nodes (map 'list (lambda (lump) (storage lump))
+ lumps)))
+ (setf (aref nodes 0) 2)
+ (assert (every #'~= (apply #'concatenate 'list nodes) '(2 3 6 9)))))
+
+431: alien strucure redefinition doesn't work as expected
+ fixed in 1.0.21.29