+211: "keywords processing"
+ a. :ALLOW-OTHER-KEYS T should allow a function to receive an odd
+ number of keyword arguments.
+ e. Compiling
+
+ (flet ((foo (&key y) (list y)))
+ (list (foo :y 1 :y 2)))
+
+ issues confusing message
+
+ ; in: LAMBDA NIL
+ ; (FOO :Y 1 :Y 2)
+ ;
+ ; caught STYLE-WARNING:
+ ; The variable #:G15 is defined but never used.
+
+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"
+ a. MAKE-SEQUENCE, COERCE, MERGE and CONCATENATE cannot deal with
+ various complicated, though recognizeable, CONS types [e.g.
+ (CONS * (CONS * NULL))
+ which according to ANSI should be recognized] (and, in SAFETY 3
+ code, should return a list of LENGTH 2 or signal an error)
+ 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.
+
+214:
+ SBCL 0.6.12.43 fails to compile
+
+ (locally
+ (declare (optimize (inhibit-warnings 0) (compilation-speed 2)))
+ (flet ((foo (&key (x :vx x-p)) (list x x-p)))
+ (foo 1 2)))
+
+ or a more simple example:
+
+ (locally
+ (declare (optimize (inhibit-warnings 0) (compilation-speed 2)))
+ (lambda (x) (declare (fixnum x)) (if (< x 0) 0 (1- x))))
+
+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.)
+
+217: "Bad type operations with FUNCTION types"
+ In sbcl.0.7.7:
+
+ * (values-type-union (specifier-type '(function (base-char)))
+ (specifier-type '(function (integer))))
+
+ #<FUN-TYPE (FUNCTION (BASE-CHAR) *)>
+
+ It causes insertion of wrong type assertions into generated
+ code. E.g.
+
+ (defun foo (x s)
+ (let ((f (etypecase x
+ (character #'write-char)
+ (integer #'write-byte))))
+ (funcall f x s)
+ (etypecase x
+ (character (write-char x s))
+ (integer (write-byte x s)))))
+
+ Then (FOO #\1 *STANDARD-OUTPUT*) signals type error.
+
+ (In 0.7.9.1 the result type is (FUNCTION * *), so Python does not
+ produce invalid code, but type checking is not accurate. Similar
+ problems exist with VALUES-TYPE-INTERSECTION.)
+
+218: "VALUES type specifier semantics"
+ (THE (VALUES ...) ...) in safe code discards extra values.
+
+ (defun test (x y) (the (values integer) (truncate x y)))
+ (test 10 4) => 2
+
+219: "DEFINE-COMPILER-MACRO in non-toplevel contexts evaluated at compile-time"
+ In sbcl-0.7.9:
+
+ * (defun foo (x)
+ (when x
+ (define-compiler-macro bar (&whole whole)
+ (declare (ignore whole))
+ (print "expanding compiler macro")
+ 1)))
+ FOO
+ * (defun baz (x) (bar))
+ [ ... ]
+ "expanding compiler macro"
+ BAZ
+ * (baz t)
+ 1
+
+220:
+ Sbcl 0.7.9 fails to compile
+
+ (multiple-value-call #'list
+ (the integer (helper))
+ nil)
+
+ Type check for INTEGER is inserted, the result of which serves as
+ the first argument of M-V-C, is inserted after evaluation of NIL. So
+ arguments of M-V-C are pushed in the wrong order. As a temporary
+ workaround type checking was disabled for M-V-Cs in 0.7.9.13. A
+ better solution would be to put a check between evaluation of
+ arguments, but it could be tricky to check result types of PROG1, IF
+ etc.
+
+222: "environment problems in PCL"
+ Evaluating
+
+ (symbol-macrolet ((x 1))
+ (defmethod foo (z)
+ (macrolet ((ml (form) `(progn ,form ,x)))
+ (ml (print x)))))
+
+ causes
+
+ debugger invoked on condition of type UNBOUND-VARIABLE:
+ The variable X is unbound.
+
+
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