+ (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)
+
+280: bogus WARNING about duplicate function definition
+ In sbcl-0.8.3 and sbcl-0.8.1.47, if BS.MIN is defined inline,
+ e.g. by
+ (declaim (inline bs.min))
+ (defun bs.min (bases) nil)
+ before compiling the file below, the compiler warns
+ Duplicate definition for BS.MIN found in one static
+ unit (usually a file).
+ when compiling
+ (declaim (special *minus* *plus* *stagnant*))
+ (defun b.*.min (&optional (x () xp) (y () yp) &rest rest)
+ (bs.min avec))
+ (define-compiler-macro b.*.min (&rest rest)
+ `(bs.min ,@rest))
+ (defun afish-d-rbd (pd)
+ (if *stagnant*
+ (b.*.min (foo-d-rbd *stagnant*))
+ (multiple-value-bind (reduce-fn initial-value)
+ (etypecase pd
+ (list (values #'bs.min 0))
+ (vector (values #'bs.min *plus*)))
+ (let ((cv-ks (cv (kpd.ks pd))))
+ (funcall reduce-fn d-rbds)))))
+ (defun bfish-d-rbd (pd)
+ (if *stagnant*
+ (b.*.min (foo-d-rbd *stagnant*))
+ (multiple-value-bind (reduce-fn initial-value)
+ (etypecase pd
+ (list (values #'bs.min *minus*))
+ (vector (values #'bs.min 0)))
+ (let ((cv-ks (cv (kpd.ks pd))))
+ (funcall reduce-fn d-rbds)))))
+
+281: COMPUTE-EFFECTIVE-METHOD error signalling.
+ (slightly obscured by a non-0 default value for
+ SB-PCL::*MAX-EMF-PRECOMPUTE-METHODS*)
+ It would be natural for COMPUTE-EFFECTIVE-METHOD to signal errors
+ when it finds a method with invalid qualifiers. However, it
+ shouldn't signal errors when any such methods are not applicable to
+ the particular call being evaluated, and certainly it shouldn't when
+ simply precomputing effective methods that may never be called.
+ (setf sb-pcl::*max-emf-precompute-methods* 0)
+ (defgeneric foo (x)
+ (:method-combination +)
+ (:method ((x symbol)) 1)
+ (:method + ((x number)) x))
+ (foo 1) -> ERROR, but should simply return 1
+
+ The issue seems to be that construction of a discriminating function
+ calls COMPUTE-EFFECTIVE-METHOD with methods that are not all applicable.
+
+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 0.8.3.10: please update this
+ bug instead of creating new ones
+
+ localtime() - called for timezone calculations in code/time.lisp
+
+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.
+
+287: PPC/Linux miscompilation or corruption in first GC
+ When the runtime is compiled with -O3 on certain PPC/Linux machines, a
+ segmentation fault is reported at the point of first triggered GC,
+ during the compilation of DEFSTRUCT WRAPPER. As a temporary workaround,
+ the runtime is no longer compiled with -O3 on PPC/Linux, but it is likely
+ that this merely obscures, not solves, the underlying problem; as and when
+ underlying problems are fixed, it would be worth trying again to provoke
+ this problem.
+
+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.
+
+296:
+ (reported by Adam Warner, sbcl-devel 2003-09-23)
+
+ The --load toplevel argument does not perform any sanitization of its
+ argument. As a result, files with Lisp pathname pattern characters
+ (#\* or #\?, for instance) or quotation marks can cause the system
+ to perform arbitrary behaviour.
+
+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))"
+
+302: Undefined type messes up DATA-VECTOR-REF expansion.
+ Compiling this file
+ (defun dis (s ei x y)
+ (declare (type (simple-array function (2)) s) (type ei ei))
+ (funcall (aref s ei) x y))
+ on sbcl-0.8.7.36/X86/Linux causes a BUG to be signalled:
+ full call to SB-KERNEL:DATA-VECTOR-REF
+
+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.
+
+305:
+ (Reported by Dave Roberts.)
+ Local INLINE/NOTINLINE declaration removes local FTYPE declaration:
+
+ (defun quux (x)
+ (declare (ftype (function () (integer 0 10)) fee)
+ (inline fee))
+ (1+ (fee)))
+
+ uses generic arithmetic with INLINE and fixnum without.
+
+306: "Imprecise unions of array types"
+ a.(defun foo (x)
+ (declare (optimize speed)
+ (type (or (array cons) (array vector)) x))
+ (elt (aref x 0) 0))
+ (foo #((0))) => TYPE-ERROR
+
+ relatedly,
+
+ 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)
+
+308: "Characters without names"
+ (reported by Bruno Haible sbcl-devel "character names are missing"
+ 2004-04-19)
+ (graphic-char-p (code-char 255))
+ => NIL
+ (char-name (code-char 255))
+ => NIL
+
+ SBCL is unsure of what to do about characters with codes in the
+ range 128-255. Currently they are treated as non-graphic, but don't
+ have names, which is not compliant with the standard. Various fixes
+ are possible, such as
+ * giving them names such as NON-ASCII-128;
+ * reducing CHAR-CODE-LIMIT to 127 (almost certainly unpopular);
+ * making the characters graphic (makes a certain amount of sense);
+ * biting the bullet and implementing Unicode (probably quite hard).
+
+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.
+
+310: "Floating point printing inaccuracy"
+ (reported by Bruno Haible sbcl-devel "print-read consistency for
+ floating point numbers" 2004-04-19)
+ (let ((x (/ -9.349640046247849d-21 -9.381494249123696d-11)))
+ (let ((y (read-from-string (write-to-string x :readably t))))
+ (eql x y)))
+ should return T but, as of sbcl-0.8.9.51, returns NIL.
+
+ That this is a bug in the printer is demonstrated by
+ (setq x1 (float -5496527/100000000000000000))
+ (setq x2 (float -54965272/1000000000000000000))
+ (integer-decode-float x1) => 15842660 -58 -1
+ (integer-decode-float x2) => 15842661 -58 -1
+ (prin1-to-string x1) => "-5.496527e-11"
+ (prin1-to-string x2) => "-5.496527e-11" ; should be different!
+
+ Note also the following comment from src/code/print.lisp:
+ ;;; NOTE: When a number is to be printed in exponential format, it is
+ ;;; scaled in floating point. Since precision may be lost in this
+ ;;; process, the guaranteed accuracy properties of FLONUM-TO-STRING
+ ;;; are lost. The difficulty is that FLONUM-TO-STRING performs
+ ;;; extensive computations with integers of similar magnitude to that
+ ;;; of the number being printed. For large exponents, the bignums
+ ;;; really get out of hand. If bignum arithmetic becomes reasonably
+ ;;; fast and the exponent range is not too large, then it might become
+ ;;; attractive to handle exponential notation with the same accuracy
+ ;;; as non-exponential notation, using the method described in the
+ ;;; Steele and White paper.
+
+ See also CSR sbcl-devel with an implementation of Berger and
+ Dybvig's algorithm for printing and a fix for reading.
+
+311: "Tokeniser not thread-safe"
+ (see also Robert Marlow sbcl-help "Multi threaded read chucking a
+ spak" 2004-04-19)
+ The tokenizer's use of *read-buffer* and *read-buffer-length* causes
+ spurious errors should two threads attempt to tokenise at the same
+ time.
+
+312:
+ (reported by Jon Dyte)
+ SBCL issues a warning "Duplicate definition of FOO" compiling
+
+ (declaim (inline foo))
+ (defun foo (x)
+ (1+ x))
+ (defun bar (y)
+ (list (foo y) (if (> y 1) (funcall (if (> y 0) #'foo #'identity) y))))
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