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:
believers in ANSI compatibility and all, (1) there's no obvious
simple way to do it (short of disabling all warnings for type
mismatches everywhere), and (2) there's a good portable
- workaround. ANSI justifies this specification by saying
+ workaround, and (3) by their own reasoning, it looks as though
+ ANSI may have gotten it wrong. ANSI justifies this specification
+ by saying
The restriction against issuing a warning for type mismatches
between a slot-initform and the corresponding slot's :TYPE
option is necessary because a slot-initform must be specified
in order to specify slot options; in some cases, no suitable
default may exist.
- In SBCL, as in CMU CL (or, for that matter, any compiler which
- really understands Common Lisp types) a suitable default does
- exist, in all cases, because the compiler understands the concept
- of functions which never return (i.e. has return type NIL, e.g.
- ERROR). Thus, as a portable workaround, you can use a call to
- some known-never-to-return function as the default. E.g.
+ However, in SBCL (as in CMU CL or, for that matter, any compiler
+ which really understands Common Lisp types) a suitable default
+ does exist, in all cases, because the compiler understands the
+ concept of functions which never return (i.e. has return type NIL).
+ Thus, as a portable workaround, you can use a call to some
+ known-never-to-return function as the default. E.g.
(DEFSTRUCT FOO
(BAR (ERROR "missing :BAR argument")
:TYPE SOME-TYPE-TOO-HAIRY-TO-CONSTRUCT-AN-INSTANCE-OF))
or
- (DECLAIM (FTYPE () NIL) MISSING-ARG)
+ (DECLAIM (FTYPE (FUNCTION () NIL) MISSING-ARG))
(DEFUN REQUIRED-ARG () ; workaround for SBCL non-ANSI slot init typing
(ERROR "missing required argument"))
(DEFSTRUCT FOO
(BAR (REQUIRED-ARG) :TYPE TRICKY-TYPE-OF-SOME-SORT)
(BLETCH (REQUIRED-ARG) :TYPE TRICKY-TYPE-OF-SOME-SORT)
(N-REFS-SO-FAR 0 :TYPE (INTEGER 0)))
- Such code will compile without complaint and work correctly either
- on SBCL or on a 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.
-
-7:
- The "byte compiling top-level form:" output ought to be condensed.
- Perhaps any number of such consecutive lines ought to turn into a
- single "byte compiling top-level forms:" line.
-
-9:
- The handling of IGNORE declarations on lambda list arguments of
- DEFMETHOD is at least weird, and in fact seems broken and useless.
- I should fix up another layer of binding, declared IGNORABLE, for
- typed lambda list arguments.
-
-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 someday perhaps I'll be motivated to look it up..
-
-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)
-
-12:
- The type system doesn't understand the KEYWORD type very well:
- (SUBTYPEP 'KEYWORD 'SYMBOL) => NIL, NIL
- It might be possible to fix this by changing the definition of
- KEYWORD to (AND SYMBOL (SATISFIES KEYWORDP)), but the type system
- would need to be a bit smarter about AND types, too:
- (SUBTYPEP '(AND SYMBOL KEYWORD) 'SYMBOL) => NIL, NIL
- (The type system does know something about AND types already,
- (SUBTYPEP '(AND INTEGER FLOAT) 'NUMBER) => T, T
- (SUBTYPEP '(AND INTEGER FIXNUM) 'NUMBER) =>T, T
- so likely this is a small patch.)
-
-13:
- Floating point infinities are screwed up. [When I was converting CMU CL
- to SBCL, I was looking for complexity to delete, and I thought it was safe
- to just delete support for floating point infinities. It wasn't: they're
- generated by the floating point hardware even when we remove support
- for them in software. -- WHN] Support for them should be restored.
-
-14:
- The ANSI syntax for non-STANDARD method combination types in CLOS is
- (DEFGENERIC FOO (X) (:METHOD-COMBINATION PROGN))
- (DEFMETHOD FOO PROGN ((X BAR)) (PRINT 'NUMBER))
- If you mess this up, omitting the PROGN qualifier in in DEFMETHOD,
- (DEFGENERIC FOO (X) (:METHOD-COMBINATION PROGN))
- (DEFMETHOD FOO ((X BAR)) (PRINT 'NUMBER))
- the error mesage is not easy to understand:
- INVALID-METHOD-ERROR was called outside the dynamic scope
- of a method combination function (inside the body of
- DEFINE-METHOD-COMBINATION or a method on the generic
- function COMPUTE-EFFECTIVE-METHOD).
- It would be better if it were more informative, a la
- The method combination type for this method (STANDARD) does
- not match the method combination type for the generic function
- (PROGN).
- Also, after you make the mistake of omitting the PROGN qualifier
- on a DEFMETHOD, doing a new DEFMETHOD with the correct qualifier
- no longer works:
- (DEFMETHOD FOO PROGN ((X BAR)) (PRINT 'NUMBER))
- gives
- INVALID-METHOD-ERROR was called outside the dynamic scope
- of a method combination function (inside the body of
- DEFINE-METHOD-COMBINATION or a method on the generic
- function COMPUTE-EFFECTIVE-METHOD).
- This is not very helpful..
-
-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.)
-
-18:
- from DTC on the CMU CL mailing list 25 Feb 2000:
-;;; Compiler fails when this file is compiled.
-;;;
-;;; Problem shows up in delete-block within ir1util.lisp. The assertion
-;;; (assert (member (functional-kind lambda) '(:let :mv-let :assignment)))
-;;; fails within bind node branch.
-;;;
-;;; Note that if c::*check-consistency* is enabled then an un-reached
-;;; entry is also reported.
-;;;
-(defun foo (val)
- (declare (values nil))
- nil)
-(defun bug (val)
- (multiple-value-call
- #'(lambda (res)
- (block nil
- (tagbody
- loop
- (when res
- (return nil))
- (go loop))))
- (foo val))
- (catch 'ccc1
- (throw 'ccc1
- (block bbbb
- (tagbody
-
- (let ((ttt #'(lambda () (go cccc))))
- (declare (special ttt))
- (return-from bbbb nil))
-
- cccc
- (return-from bbbb nil))))))
-
-19:
- (I *think* this is a bug. It certainly seems like strange behavior. But
- the ANSI spec is scary, dark, and deep..)
- (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)
- DTC's recommended workaround from the mailing list 3 Mar 2000:
- (setf (pcl::find-class 'ccc1) (pcl::find-class 'ccc))
-
-22:
- The ANSI spec, in section "22.3.5.2 Tilde Less-Than-Sign: Logical Block",
- says that an error is signalled if ~W, ~_, ~<...~:>, ~I, or ~:T is used
- inside "~<..~>" (without the colon modifier on the closing syntax).
- However, SBCL doesn't do this:
- * (FORMAT T "~<munge~wegnum~>" 12)
- munge12egnum
- NIL
-
-23:
- When too many files are opened, OPEN will fail with an
- uninformative error message
- error in function OPEN: error opening #P"/tmp/foo.lisp": NIL
- instead of saying that too many files are open.
-
-24:
- Right now, when COMPILE-FILE has a read error, it actually pops
- you into the debugger before giving up on the file. It should
- instead handle the error, perhaps issuing (and handling)
- a secondary error "caught ERROR: unrecoverable error during compilation"
- and then return with FAILURE-P true,
-
-25:
- from CMU CL mailing list 01 May 2000
-
-I realize I can take care of this by doing (proclaim (ignore pcl::.slots1.))
-but seeing as .slots0. is not-exported, shouldn't it be ignored within the
-+expansion
-when not used?
-
-In: DEFMETHOD FOO-BAR-BAZ (RESOURCE-TYPE)
- (DEFMETHOD FOO-BAR-BAZ
- ((SELF RESOURCE-TYPE))
- (SETF (SLOT-VALUE SELF 'NAME) 3))
---> BLOCK MACROLET PCL::FAST-LEXICAL-METHOD-FUNCTIONS
---> PCL::BIND-FAST-LEXICAL-METHOD-MACROS MACROLET
---> PCL::BIND-LEXICAL-METHOD-FUNCTIONS LET PCL::BIND-ARGS LET* PCL::PV-BINDING
---> PCL::PV-BINDING1 PCL::PV-ENV LET
-==>
- (LET ((PCL::.SLOTS0. #))
- (PROGN SELF)
- (BLOCK FOO-BAR-BAZ
- (LET #
- #)))
-Warning: Variable PCL::.SLOTS0. defined but never used.
-
-Compilation unit finished.
- 1 warning
-
-#<Standard-Method FOO-BAR-BAZ (RESOURCE-TYPE) {480918FD}>
-
-26:
- reported by Sam Steingold on the cmucl-imp mailing list 12 May 2000:
-
-Also, there is another bug: `array-displacement' should return an array
-or nil as first value (as per ANSI CL), while CMUCL declares it as
-returning an array as first value always.
-
-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.
-
-29:
- some sort of bug in inlining and RETURN-FROM in sbcl-0.6.5: Compiling
- (DEFUN BAR? (X)
- (OR (NAR? X)
- (BLOCK USED-BY-SOME-Y?
- (FLET ((FROB (STK)
- (DOLIST (Y STK)
- (UNLESS (REJECTED? Y)
- (RETURN-FROM USED-BY-SOME-Y? T)))))
- (DECLARE (INLINE FROB))
- (FROB (RSTK X))
- (FROB (MRSTK X)))
- NIL)))
- gives
- error in function SB-KERNEL:ASSERT-ERROR:
- The assertion (EQ (SB-C::CONTINUATION-KIND SB-C::CONT) :BLOCK-START) failed.
- This is still present in sbcl-0.6.8.
-
-31:
- In some cases the compiler believes type declarations on array
- elements without checking them, e.g.
- (DECLAIM (OPTIMIZE (SAFETY 3) (SPEED 1) (SPACE 1)))
- (DEFSTRUCT FOO A B)
- (DEFUN BAR (X)
- (DECLARE (TYPE (SIMPLE-ARRAY CONS 1) X))
- (WHEN (CONSP (AREF X 0))
- (PRINT (AREF X 0))))
- (BAR (VECTOR (MAKE-FOO :A 11 :B 12)))
- prints
- #S(FOO :A 11 :B 12)
- in SBCL 0.6.5 (and also in CMU CL 18b). This does not happen for
- all cases, e.g. the type assumption *is* checked if the array
- elements are declared to be of some structure type instead of CONS.
-
-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.
+ Such code should compile without complaint and work correctly either
+ on SBCL or on any other completely compliant Common Lisp system.
+
+ b: &AUX argument in a boa-constructor without a default value means
+ "do not initilize this slot" and does not cause type error. But
+ an error may be signalled at read time and it would be good if
+ SBCL did it.
+
+ d: (fixed in 0.8.1.5)
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.
-34:
- WHN test case: Compile this file:
- (eval-when (:compile-toplevel :load-toplevel :execute)
- (defclass a-class () (a)))
- (defconstant +a-constant+ (make-instance 'a-class))
- (defconstant +another-constant+ (vector +a-constant+))
- as reported by Robert Strandh on the CMU CL mailing list 12 Jun 2000:
- $ cat xx.lisp
- (defconstant +a-constant+ (make-instance 'a-class))
- (defconstant +another-constant+ (vector +a-constant+))
- $ lisp
- CMU Common Lisp release x86-linux 2.4.19 8 February 2000 build 456,
- running on
- bobby
- Send bug reports and questions to your local CMU CL maintainer,
- or to pvaneynd@debian.org
- or to cmucl-help@cons.org. (prefered)
- type (help) for help, (quit) to exit, and (demo) to see the demos
- Loaded subsystems:
- Python 1.0, target Intel x86
- CLOS based on PCL version: September 16 92 PCL (f)
- * (defclass a-class () ())
- #<STANDARD-CLASS A-CLASS {48027BD5}>
- * (compile-file "xx.lisp")
- Python version 1.0, VM version Intel x86 on 12 JUN 00 08:12:55 am.
- Compiling:
- /home/strandh/Research/Functional/Common-Lisp/CLIM/Development/McCLIM
- /xx.lisp 12 JUN 00 07:47:14 am
- Compiling Load Time Value of (PCL::GET-MAKE-INSTANCE-FUNCTION-SYMBOL
- '(A-CLASS NIL NIL)):
- Byte Compiling Top-Level Form:
- Error in function C::DUMP-STRUCTURE: Attempt to dump invalid
- structure:
- #<A-CLASS {4803A5B5}>
- How did this happen?
+ 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
E.g. compiling and loading
(DECLAIM (OPTIMIZE (SAFETY 3)))
(DEFUN FACTORIAL (X) (GAMMA (1+ X)))
- (DECLAIM (FTYPE (FUNCTION (UNSIGNED-BYTE) FACTORIAL)))
+ (DEFUN GAMMA (X) X)
+ (DECLAIM (FTYPE (FUNCTION (UNSIGNED-BYTE)) FACTORIAL))
(DEFUN FOO (X)
(COND ((> (FACTORIAL X) 1.0E6)
(FORMAT T "too big~%"))
then executing
(FOO 1.5)
will cause the INTEGERP case to be selected, giving bogus output a la
- exactly 1.33..
+ exactly 2.5
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
that arbitrary functions check their argument types. (It might
make sense to add another flag (CHECKED?) to DEFKNOWN to
identify functions which *do* check their argument types.)
-
-38:
- DEFMETHOD doesn't check the syntax of &REST argument lists properly,
- accepting &REST even when it's not followed by an argument name:
- (DEFMETHOD FOO ((X T) &REST) NIL)
-
-39:
- On the CMU CL mailing list 26 June 2000, Douglas Crosher wrote
-
- Hannu Rummukainen wrote:
- ...
- > There's something weird going on with the compilation of the attached
- > code. Compiling and loading the file in a fresh lisp, then invoking
- > (test-it) gives
- Thanks for the bug report, nice to have this one fixed. It was a bug
- in the x86 backend, the < VOP. A fix has been committed to the main
- source, see the file compiler/x86/float.lisp.
-
- Probably the same bug exists in SBCL.
-
-40:
- TYPEP treats the result of UPGRADED-ARRAY-ELEMENT-TYPE as gospel,
- so that (TYPEP (MAKE-ARRAY 3) '(VECTOR SOMETHING-NOT-DEFINED-YET))
- returns (VALUES T T). Probably it should be an error instead,
- complaining that the type SOMETHING-NOT-DEFINED-YET is not defined.
-
-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.
+ (Also, verify that the compiler handles declared function
+ return types as assertions.)
42:
The definitions of SIGCONTEXT-FLOAT-REGISTER and
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.
-
-44:
- ANSI specifies DEFINE-SYMBOL-MACRO, but it's not defined in SBCL.
- CMU CL added it ca. Aug 13, 2000, after some discussion on the mailing
- list, and it is probably possible to use substantially the same
- patches to add it to SBCL.
-
-45:
- a slew of floating-point-related errors reported by Peter Van Eynde
- on July 25, 2000:
- a: (SQRT -9.0) fails, because SB-KERNEL::COMPLEX-SQRT is undefined.
- Similarly, COMPLEX-ASIN, COMPLEX-ACOS, COMPLEX-ACOSH, and others
- aren't found.
- 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:
- (/ 1 0.0)
- (/ 1 0.0d0)
- (EXPT 10.0 1000)
- (EXPT 10.0d0 1000)
- PVE's regression tests want them to raise errors. SBCL
- generates the infinities instead, which may or may not be
- conforming behavior, but then blow it by being unable to
- output the infinities, since support for infinities is generally
- broken, and in particular SB-IMPL::OUTPUT-FLOAT-INFINITY is
- undefined.
- 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:
- a: (COERCE (QUOTE (A B C)) (QUOTE (VECTOR * 4)))
- => #(A B C)
- In general lengths of array type specifications aren't
- checked by COERCE, so it fails when the spec is
- (VECTOR 4), (STRING 2), (SIMPLE-BIT-VECTOR 3), or whatever.
- b: CONCATENATE has the same problem of not checking the length
- of specified output array types. MAKE-SEQUENCE and MAP and
- MERGE also have the same problem.
- c: (COERCE 'AND 'FUNCTION) returns something related to
- (MACRO-FUNCTION 'AND), but ANSI says it should raise an error.
- d: ELT signals SIMPLE-ERROR if its index argument
- isn't a valid index for its sequence argument, but should
- signal TYPE-ERROR instead.
- e: FILE-LENGTH is supposed to signal a type error when its
- argument is not a stream associated with a file, but doesn't.
- f: (FLOAT-RADIX 2/3) should signal an error instead of
- returning 2.
- g: (LOAD "*.lsp") should signal FILE-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.
- j: (PARSE-NAMESTRING (COERCE (LIST #\f #\o #\o (CODE-CHAR 0) #\4 #\8)
- (QUOTE STRING)))
- should probably signal an error instead of making a pathname with
- a null byte in it.
- 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:
- a: (DEFCLASS FOO () (A B A)) should signal a PROGRAM-ERROR, and
- doesn't.
- b: (DEFCLASS FOO () (A B A) (:DEFAULT-INITARGS X A X B)) should
- signal a PROGRAM-ERROR, and doesn't.
- c: (DEFCLASS FOO07 NIL ((A :ALLOCATION :CLASS :ALLOCATION :CLASS))),
- and other DEFCLASS forms with duplicate specifications in their
- slots, should signal a PROGRAM-ERROR, and doesn't.
- 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:
- a: (SYMBOL-MACROLET ((T TRUE)) ..) should probably signal
- PROGRAM-ERROR, but SBCL accepts it instead.
- b: SYMBOL-MACROLET should refuse to bind something which is
- declared as a global variable, signalling PROGRAM-ERROR.
- c: SYMBOL-MACROLET should signal PROGRAM-ERROR if something
- it binds is declared SPECIAL inside.
-
-49:
- LOOP bugs reported by Peter Van Eynde July 25, 2000:
- a: (LOOP WITH (A B) DO (PRINT 1)) is a syntax error according to
- the definition of WITH clauses given in the ANSI spec, but
- compiles and runs happily in SBCL.
- b: a messy one involving package iteration:
-interpreted Form: (LET ((PACKAGE (MAKE-PACKAGE "LOOP-TEST"))) (INTERN "blah" PACKAGE) (LET ((BLAH2 (INTERN "blah2" PACKAGE))) (EXPORT BLAH2 PACKAGE)) (LIST (SORT (LOOP FOR SYM BEING EACH PRESENT-SYMBOL OF PACKAGE FOR SYM-NAME = (SYMBOL-NAME SYM) COLLECT SYM-NAME) (FUNCTION STRING<)) (SORT (LOOP FOR SYM BEING EACH EXTERNAL-SYMBOL OF PACKAGE FOR SYM-NAME = (SYMBOL-NAME SYM) COLLECT SYM-NAME) (FUNCTION STRING<))))
-Should be: (("blah" "blah2") ("blah2"))
-SBCL: (("blah") ("blah2"))
- * (LET ((X 1)) (LOOP FOR I BY (INCF X) FROM X TO 10 COLLECT I))
- doesn't work -- SBCL's LOOP says BY isn't allowed in a FOR clause.
-
-50:
- type system errors reported by Peter Van Eynde July 25, 2000:
- a: (SUBTYPEP 'BIGNUM 'INTEGER) => NIL, NIL
- but should be (VALUES T T) instead.
- b: (SUBTYPEP 'EXTENDED-CHAR 'CHARACTER) => NIL, NIL
- but should be (VALUES T T) instead.
- c: (SUBTYPEP '(INTEGER (0) (0)) 'NIL) dies with nested errors.
- d: In general, the system doesn't like '(INTEGER (0) (0)) -- it
- blows up at the level of SPECIFIER-TYPE with
- "Lower bound (0) is greater than upper bound (0)." Probably
- SPECIFIER-TYPE should return NIL instead.
- e: (TYPEP 0 '(COMPLEX (EQL 0)) fails with
- "Component type for Complex is not numeric: (EQL 0)."
- This might be easy to fix; the type system already knows
- that (SUBTYPEP '(EQL 0) 'NUMBER) is true.
- f: The type system doesn't know about the condition system,
- so that e.g. (TYPEP 'SIMPLE-ERROR 'ERROR)=>NIL.
- g: The type system isn't all that smart about relationships
- between hairy types, as shown in the type.erg test results,
- e.g. (SUBTYPEP 'CONS '(NOT ATOM)) => NIL, NIL.
-
-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.
- b: READ should probably return READER-ERROR, not the bare
- arithmetic error, when input a la "1/0" or "1e1000" causes
- an arithmetic error.
-
-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.)
-
-53:
- another error from Peter Van Eynde 5 September 2000:
- (FORMAT NIL "~F" "FOO") should work, but instead reports an error.
- PVE submitted a patch to deal with this bug, but it exposes other
- comparably serious bugs, so I didn't apply it. It looks as though
- the FORMAT code needs a fair amount of rewriting in order to comply
- with the various details of the ANSI spec.
-
-54:
- The implementation of #'+ returns its single argument without
- type checking, e.g. (+ "illegal") => "illegal".
-
-55:
- In sbcl-0.6.7, there is no doc string for CL:PUSH, probably
- because it's defined with the DEFMACRO-MUNDANELY macro and something
- is wrong with doc string setting in that macro.
-
-56:
- Attempting to use COMPILE on something defined by DEFMACRO fails:
- (DEFMACRO FOO (X) (CONS X X))
- (COMPILE 'FOO)
-Error in function C::GET-LAMBDA-TO-COMPILE:
- #<Closure Over Function "DEFUN (SETF MACRO-FUNCTION)" {480E21B1}> was defined in a non-null environment.
-
-58:
- (SUBTYPEP '(AND ZILCH INTEGER) 'ZILCH)
- => NIL, NIL
-
-59:
- CL:*DEFAULT-PATHNAME-DEFAULTS* doesn't behave as ANSI suggests (reflecting
- current working directory). And there's no supported way to update
- or query the current working directory (a la Unix "chdir" and "pwd"),
- which is functionality that ILISP needs (and currently gets with low-level
- hacks).
-
-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
the new output block should start indented 2 or more characters
rightward of the correct location.
-65:
- (probably related to bug #70)
- As reported by Carl Witty on submit@bugs.debian.org 1999-05-08,
- compiling this file
-(in-package "CL-USER")
-(defun equal-terms (termx termy)
- (labels
- ((alpha-equal-bound-term-lists (listx listy)
- (or (and (null listx) (null listy))
- (and listx listy
- (let ((bindings-x (bindings-of-bound-term (car listx)))
- (bindings-y (bindings-of-bound-term (car listy))))
- (if (and (null bindings-x) (null bindings-y))
- (alpha-equal-terms (term-of-bound-term (car listx))
- (term-of-bound-term (car listy)))
- (and (= (length bindings-x) (length bindings-y))
- (prog2
- (enter-binding-pairs (bindings-of-bound-term (car listx))
- (bindings-of-bound-term (car listy)))
- (alpha-equal-terms (term-of-bound-term (car listx))
- (term-of-bound-term (car listy)))
- (exit-binding-pairs (bindings-of-bound-term (car listx))
- (bindings-of-bound-term (car listy)))))))
- (alpha-equal-bound-term-lists (cdr listx) (cdr listy)))))
-
- (alpha-equal-terms (termx termy)
- (if (and (variable-p termx)
- (variable-p termy))
- (equal-bindings (id-of-variable-term termx)
- (id-of-variable-term termy))
- (and (equal-operators-p (operator-of-term termx) (operator-of-term termy))
- (alpha-equal-bound-term-lists (bound-terms-of-term termx)
- (bound-terms-of-term termy))))))
-
- (or (eq termx termy)
- (and termx termy
- (with-variable-invocation (alpha-equal-terms termx termy))))))
- causes an assertion failure
- The assertion (EQ (C::LAMBDA-TAIL-SET C::CALLER)
- (C::LAMBDA-TAIL-SET (C::LAMBDA-HOME C::CALLEE))) failed.
-
- Bob Rogers reports (1999-07-28 on cmucl-imp@cons.org) a smaller test
- case with the same problem:
-(defun parse-fssp-alignment ()
- ;; Given an FSSP alignment file named by the argument . . .
- (labels ((get-fssp-char ()
- (get-fssp-char))
- (read-fssp-char ()
- (get-fssp-char)))
- ;; Stub body, enough to tickle the bug.
- (list (read-fssp-char)
- (read-fssp-char))))
-
-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)
-
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.
-68:
- As reported by Daniel Solaz on cmucl-help@cons.org 2000-11-23,
- SXHASH returns the same value for all non-STRUCTURE-OBJECT instances,
- notably including all PCL instances. There's a limit to how much
- SXHASH can do to return unique values for instances, but at least
- it should probably look at the class name, the way that it does
- for STRUCTURE-OBJECTs.
-
-69:
- As reported by Martin Atzmueller on the sbcl-devel list 2000-11-22,
- > There remains one issue, that is a bug in SBCL:
- > According to my interpretation of the spec, the ":" and "@" modifiers
- > should appear _after_ the comma-seperated arguments.
- > Well, SBCL (and CMUCL for that matter) accept
- > (ASSERT (STRING= (FORMAT NIL "~:8D" 1) " 1"))
- > where the correct way (IMHO) should be
- > (ASSERT (STRING= (FORMAT NIL "~8:D" 1) " 1"))
- Probably SBCL should stop accepting the "~:8D"-style format arguments,
- or at least issue a warning.
-
-70:
- (probably related to bug #65)
- The compiler doesn't like &OPTIONAL arguments in LABELS and FLET
- forms. E.g.
- (DEFUN FIND-BEFORE (ITEM SEQUENCE &KEY (TEST #'EQL))
- (LABELS ((FIND-ITEM (OBJ SEQ TEST &OPTIONAL (VAL NIL))
- (LET ((ITEM (FIRST SEQ)))
- (COND ((NULL SEQ)
- (VALUES NIL NIL))
- ((FUNCALL TEST OBJ ITEM)
- (VALUES VAL SEQ))
- (T
- (FIND-ITEM OBJ (REST SEQ) TEST (NCONC VAL `(,ITEM))))))))
- (FIND-ITEM ITEM SEQUENCE TEST)))
- from David Young's bug report on cmucl-help@cons.org 30 Nov 2000
- causes sbcl-0.6.9 to fail with
- error in function SB-KERNEL:ASSERT-ERROR:
- The assertion (EQ (SB-C::LAMBDA-TAIL-SET SB-C::CALLER)
- (SB-C::LAMBDA-TAIL-SET
- (SB-C::LAMBDA-HOME SB-C::CALLEE))) failed.
-
-71:
- (DECLAIM (OPTIMIZE ..)) doesn't work. E.g. even after
- (DECLAIM (OPTIMIZE (SPEED 3))), things are still optimized with
- the previous SPEED policy. This bug will probably get fixed in
- 0.6.9.x in a general cleanup of optimization policy.
-
-72:
- (DECLAIM (OPTIMIZE ..)) doesn't work properly inside LOCALLY forms.
-
-74:
- As noted in the ANSI specification for COERCE, (COERCE 3 'COMPLEX)
- gives a result which isn't COMPLEX. The result type optimizer
- for COERCE doesn't know this, perhaps because it was written before
- ANSI threw this curveball: the optimizer thinks that COERCE always
- returns a result of the specified type. Thus while the interpreted
- function
- (DEFUN TRICKY (X) (TYPEP (COERCE X 'COMPLEX) 'COMPLEX))
- returns the correct result,
- (TRICKY 3) => NIL
- the compiled function
- (COMPILE 'TRICKY)
- does not:
- (TRICKY 3) => T
-
-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.
-
-
-KNOWN BUGS RELATED TO THE IR1 INTERPRETER
-
-(Note: At some point, the pure interpreter (actually a semi-pure
-interpreter aka "the IR1 interpreter") will probably go away, replaced
-by constructs like
- (DEFUN EVAL (X) (FUNCALL (COMPILE NIL (LAMBDA ..)))))
-and at that time these bugs should either go away automatically or
-become more tractable to fix. Until then, they'll probably remain,
-since some of them aren't considered urgent, and the rest are too hard
-to fix as long as so many special cases remain. After the IR1
-interpreter goes away is also the preferred time to start
-systematically exterminating cases where debugging functionality
-(backtrace, breakpoint, etc.) breaks down, since getting rid of the
-IR1 interpreter will reduce the number of special cases we need to
-support.)
-
-IR1-1:
- The FUNCTION special operator doesn't check properly whether its
- argument is a function name. E.g. (FUNCTION (X Y)) returns a value
- instead of failing with an error. (Later attempting to funcall the
- value does cause an error.)
-
-IR1-2:
- COMPILED-FUNCTION-P bogusly reports T for interpreted functions:
- * (DEFUN FOO (X) (- 12 X))
- FOO
- * (COMPILED-FUNCTION-P #'FOO)
- T
-
-IR1-3:
- Executing
- (DEFVAR *SUPPRESS-P* T)
- (EVAL '(UNLESS *SUPPRESS-P*
- (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
- (FORMAT T "surprise!"))))
- prints "surprise!". Probably the entire EVAL-WHEN mechanism ought to be
- rewritten from scratch to conform to the ANSI definition, abandoning
- the *ALREADY-EVALED-THIS* hack which is used in sbcl-0.6.8.9 (and
- in the original CMU CL source, too). This should be easier to do --
- though still nontrivial -- once the various IR1 interpreter special
- cases are gone.
-
-IR1-3a:
- EVAL-WHEN's idea of what's a toplevel form is even more screwed up
- than the example in IR1-3 would suggest, since COMPILE-FILE and
- COMPILE both print both "right now!" messages when compiling the
- following code,
- (LAMBDA (X)
- (COND (X
- (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
- (PRINT "yes! right now!"))
- "yes!")
- (T
- (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
- (PRINT "no! right now!"))
- "no!")))
- and while EVAL doesn't print the "right now!" messages, the first
- FUNCALL on the value returned by EVAL causes both of them to be printed.
-
-IR1-4:
- 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.]
+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.)
+
+ (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
+ 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.)
+
+ 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
+ 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.
+ 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-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
+ (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.
+
+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).
+
+ Daniel Barlow doesn't know what fixed this, but observes that it
+ doesn't seem to be the case in 0.8.7.3 any more. Instead, (ROOM T)
+ in a fresh SBCL causes
+
+ debugger invoked on a SB-INT:BUG in thread 5911:
+ failed AVER: "(SAP= CURRENT END)"
+
+ unless a GC has happened beforehand.
+
+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..
+
+ (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
+ 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.
+
+ (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,
+ 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.
+
+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.
+
+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
+ 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.)
+
+ [ 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,
+ * (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
+
+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.)
+
+ This is probably the same bug as 216
+
+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.
+
+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)
+
+188: "compiler performance fiasco involving type inference and UNION-TYPE"
+ (time (compile
+ nil
+ '(lambda ()
+ (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))))))
+
+ 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)
+ 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.
+
+ [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)
+ (FORMAT NIL "~S IS ~S, Y = ~S"
+ (CAR X)
+ (TYPECASE (CAR X)
+ (INTEGER 'INTEGER)
+ (T '(NOT INTEGER)))
+ Y)))
+
+ (FOO ' (1 . 2)) => "NIL IS INTEGER, Y = 1"
+
+ 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.
+
+206: ":SB-FLUID feature broken"
+ (reported by Antonio Martinez-Shotton sbcl-devel 2002-10-07)
+ Enabling :SB-FLUID in the target-features list in sbcl-0.7.8 breaks
+ the build.
+
+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"
+ a. FIND and POSITION currently signal errors when given non-NIL for
+ both their :TEST and (deprecated) :TEST-NOT arguments, but by
+ ANSI 17.2 "the consequences are unspecified", which by ANSI 1.4.2
+ means that the effect is "unpredictable but harmless". It's not
+ clear what that actually means; it may preclude conforming
+ implementations from signalling errors.
+ b. COUNT, REMOVE and the like give priority to a :TEST-NOT argument
+ when conflict occurs. As a quality of implementation issue, it
+ might be preferable to treat :TEST and :TEST-NOT as being in some
+ sense the same &KEY, and effectively take the first test function in
+ the argument list.
+ c. Again, a quality of implementation issue: it would be good to issue a
+ STYLE-WARNING at compile-time for calls with :TEST-NOT, and a
+ WARNING for calls with both :TEST and :TEST-NOT; possibly this
+ latter should be WARNed about at execute-time too.
+
+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.)
+
+ This is probably the same bug as 162
+
+235: "type system and inline expansion"
+ a.
+ (declaim (ftype (function (cons) number) acc))
+ (declaim (inline acc))
+ (defun acc (c)
+ (the number (car c)))
+
+ (defun foo (x y)
+ (values (locally (declare (optimize (safety 0)))
+ (acc x))
+ (locally (declare (optimize (safety 3)))
+ (acc y))))
+
+ (foo '(nil) '(t)) => NIL, T.
+
+ As of 0.9.15.41 this seems to be due to ACC being inlined only once
+ inside FOO, which results in the second call reusing the FUNCTIONAL
+ resulting from the first -- which doesn't check the type.
+
+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).
+
+238: "REPL compiler overenthusiasm for CLOS code"
+ From the REPL,
+ * (defclass foo () ())
+ * (defmethod bar ((x foo) (foo foo)) (call-next-method))
+ causes approximately 100 lines of code deletion notes. Some
+ discussion on this issue happened under the title 'Three "interesting"
+ bugs in PCL', resulting in a fix for this oververbosity from the
+ compiler proper; however, the problem persists in the interactor
+ because the notion of original source is not preserved: for the
+ compiler, the original source of the above expression is (DEFMETHOD
+ BAR ((X FOO) (FOO FOO)) (CALL-NEXT-METHOD)), while by the time the
+ compiler gets its hands on the code needing compilation from the REPL,
+ it has been macroexpanded several times.
+
+ A symptom of the same underlying problem, reported by Tony Martinez:
+ * (handler-case
+ (with-input-from-string (*query-io* " no")
+ (yes-or-no-p))
+ (simple-type-error () 'error))
+ ; in: LAMBDA NIL
+ ; (SB-KERNEL:FLOAT-WAIT)
+ ;
+ ; note: deleting unreachable code
+ ; compilation unit finished
+ ; printed 1 note
+
+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)
+
+276:
+ b. The same as in a., but using MULTIPLE-VALUE-SETQ instead of SETQ.
+ c. (defvar *faa*)
+ (defmethod faa ((*faa* double-float))
+ (set '*faa* (when (< *faa* 0) (- *faa*)))
+ (1+ *faa*))
+ (faa 1d0) => type error
+
+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 supeseding 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.
+
+332: "fasl stack inconsistency in structure redefinition"
+ (reported by Tim Daly Jr sbcl-devel 2004-05-06)
+ Even though structure redefinition is undefined by the standard, the
+ following behaviour is suboptimal: running
+ (defun stimulate-sbcl ()
+ (let ((filename (format nil "/tmp/~A.lisp" (gensym))))
+ ;;create a file which redefines a structure incompatibly
+ (with-open-file (f filename :direction :output :if-exists :supersede)
+ (print '(defstruct astruct foo) f)
+ (print '(defstruct astruct foo bar) f))
+ ;;compile and load the file, then invoke the continue restart on
+ ;;the structure redefinition error
+ (handler-bind ((error (lambda (c) (continue c))))
+ (load (compile-file filename)))))
+ (stimulate-sbcl)
+ and choosing the CONTINUE restart yields the message
+ debugger invoked on a SB-INT:BUG in thread 27726:
+ fasl stack not empty when it should be
+
+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.
+
+354: XEPs in backtraces
+ Under default compilation policy
+ (defun test ()
+ (throw :unknown t))
+ (test)
+ Has the XEP for TEST in the backtrace, not the TEST frame itself.
+ (sparc and x86 at least)
+
+ Since SBCL 0.8.20.1 this is hidden unless *SHOW-ENTRY-POINT-DETAILS*
+ is true (instead there appear two TEST frames at least on ppc). The
+ underlying cause seems to be that SB-C::TAIL-ANNOTATE will not merge
+ the tail-call for the XEP, since Python has by that time proved that
+ the function can never return; same happens if the function holds an
+ unconditional call to ERROR.
+
+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)
+ ]
+
+357: defstruct inheritance of initforms
+ (reported by Bruno Haible)
+ When defstruct and defclass (with :metaclass structure-class) are mixed,
+ 1. some slot initforms are ignored by the DEFSTRUCT generated constructor
+ function, and
+ 2. all slot initforms are ignored by MAKE-INSTANCE. (This can be arguably
+ OK for initforms that were given in a DEFSTRUCT form, but for those
+ given in a DEFCLASS form, I think it qualifies as a bug.)
+ Test case:
+ (defstruct structure02a
+ slot1
+ (slot2 t)
+ (slot3 (floor pi)))
+ (defclass structure02b (structure02a)
+ ((slot4 :initform -44)
+ (slot5)
+ (slot6 :initform t)
+ (slot7 :initform (floor (* pi pi)))
+ (slot8 :initform 88))
+ (:metaclass structure-class))
+ (defstruct (structure02c (:include structure02b (slot8 -88)))
+ slot9
+ (slot10 t)
+ (slot11 (floor (exp 3))))
+ ;; 1. Form:
+ (let ((a (make-structure02c)))
+ (list (structure02c-slot4 a)
+ (structure02c-slot5 a)
+ (structure02c-slot6 a)
+ (structure02c-slot7 a)))
+ Expected: (-44 nil t 9)
+ Got: (SB-PCL::..SLOT-UNBOUND.. SB-PCL::..SLOT-UNBOUND..
+ SB-PCL::..SLOT-UNBOUND.. SB-PCL::..SLOT-UNBOUND..)
+ ;; 2. Form:
+ (let ((b (make-instance 'structure02c)))
+ (list (structure02c-slot2 b)
+ (structure02c-slot3 b)
+ (structure02c-slot4 b)
+ (structure02c-slot6 b)
+ (structure02c-slot7 b)
+ (structure02c-slot8 b)
+ (structure02c-slot10 b)
+ (structure02c-slot11 b)))
+ Expected: (t 3 -44 t 9 -88 t 20)
+ Got: (0 0 0 0 0 0 0 0)
+
+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>
+
+369: unlike-an-intersection behavior of VALUES-TYPE-INTERSECTION
+ In sbcl-0.8.18.2, the identity $(x \cap y \cap y)=(x \cap y)$
+ does not hold for VALUES-TYPE-INTERSECTION, even for types which
+ can be intersected exactly, so that ASSERTs fail in this test case:
+ (in-package :cl-user)
+ (let ((types (mapcar #'sb-c::values-specifier-type
+ '((values (vector package) &optional)
+ (values (vector package) &rest t)
+ (values (vector hash-table) &rest t)
+ (values (vector hash-table) &optional)
+ (values t &optional)
+ (values t &rest t)
+ (values nil &optional)
+ (values nil &rest t)
+ (values sequence &optional)
+ (values sequence &rest t)
+ (values list &optional)
+ (values list &rest t)))))
+ (dolist (x types)
+ (dolist (y types)
+ (let ((i (sb-c::values-type-intersection x y)))
+ (assert (sb-c::type= i (sb-c::values-type-intersection i x)))
+ (assert (sb-c::type= i (sb-c::values-type-intersection i y)))))))
+
+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.
+
+380: Accessor redefinition fails because of old accessor name
+ When redefining an accessor, SB-PCL::FIX-SLOT-ACCESSORS may try to
+ find the generic function named by the old accessor name using
+ ENSURE-GENERIC-FUNCTION and then remove the old accessor's method in
+ the GF. If the old name does not name a function, or if the old name
+ does not name a generic function, no attempt to find the GF or remove
+ any methods is made.
+
+ However, if an unrelated GF with an incompatible lambda list exists,
+ the class redefinition will fail when SB-PCL::REMOVE-READER-METHOD
+ tries to find and remove a method with an incompatible lambda list
+ from the unrelated generic function.
+
+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").
+
+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.
+
+395: Unicode and streams
+ One of the remaining problems in SBCL's Unicode support is the lack
+ of generality in certain streams.
+ a. FILL-POINTER-STREAMs: SBCL refuses to write (e.g. using FORMAT)
+ to streams made from strings that aren't character strings with
+ fill-pointers:
+ (let ((v (make-array 5 :fill-pointer 0 :element-type 'standard-char)))
+ (format v "foo")
+ v)
+ should return a non-simple base string containing "foo" but
+ instead errors.
+
+ (reported on sbcl-help by "tichy")
+
+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.
+
+402: "DECLAIM DECLARATION does not inform the PCL code-walker"
+ reported by Vincent Arkesteijn:
+
+ (declaim (declaration foo))
+ (defgeneric bar (x))
+ (defmethod bar (x)
+ (declare (foo x))
+ x)
+
+ ==> WARNING: The declaration FOO is not understood by
+ SB-PCL::SPLIT-DECLARATIONS.
+ Please put FOO on one of the lists SB-PCL::*NON-VAR-DECLARATIONS*,
+ SB-PCL::*VAR-DECLARATIONS-WITH-ARG*, or
+ SB-PCL::*VAR-DECLARATIONS-WITHOUT-ARG*.
+ (Assuming it is a variable declaration without argument).
+
+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.
+
+405: a TYPE-ERROR in MERGE-LETS exercised at DEBUG 3
+ In sbcl-0.9.16.21 on linux/86, compiling
+ (declaim (optimize (debug 3)))
+ (defstruct foo bar)
+ (let ()
+ (flet ((i (x) (frob x (foo-bar foo))))
+ (i :five)))
+ causes a TYPE-ERROR
+ The value NIL is not of type SB-C::PHYSENV.
+ in MERGE-LETS.
+
+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 ...)
+
+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.
+
+411: NAN issues on x86-64
+ Test :NAN-COMPARISONS in float.pure.lisp fails on x86-64, and has been
+ disabled on those platforms. Since x86 does not exhibit any problems
+ the problem is probably with the new FP implementation.
+
+413: type-errors in ROOM
+
+ (defvar *a* (make-array (expt 2 27)))
+ (room)
+
+ Causes a type-error on 32bit SBCL, as various byte-counts in ROOM
+ implementation overrun fixnums.
+
+ This was fixed in 1.0.4.89, but the patch was reverted as it caused
+ ROOM to cons sufficiently to make running it in a loop deadly on
+ GENCGC: newly allocated objects survived to generation 1, where next
+ call to ROOM would see them, and allocate even more...
+
+ Reported by Faré Rideau on sbcl-devel.
+
+414: strange DISASSEMBLE warning
+
+ Compiling and disassembling
+
+ (defun disassemble-source-form-bug (x y z)
+ (declare (optimize debug))
+ (list x y z))
+
+ Gives
+
+ WARNING: bogus form-number in form! The source file has probably
+ been changed too much to cope with.
+
+415: Issues creating large arrays on x86-64/Linux and x86/Darwin
+
+ (make-array (1- array-dimension-limit))
+
+ causes a GC invariant violation on x86-64/Linux, and
+ an unhandled SIGILL on x86/Darwin.
+
+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.
+
+
+
+
projects / sbcl.git / blobdiff