the program loops endlessly instead of printing the object.
-KNOWN BUGS RELATED TO THE IR1 INTERPRETER
+NOTES:
-(Note: At some point, the 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 go away automatically. Until then,
-they'll probably remain, since they're not considered urgent.
-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.)
+There is also some information on bugs in the manual page and
+in the TODO file. Eventually more such information may move here.
-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
+The gaps in the number sequence belong to old bugs which have been
+fixed.
KNOWN BUGS OF NO SPECIAL CLASS:
-(Note:
- * There is also some information on bugs in the manual page and
- in the TODO file. Eventually more such information may move here.
- * The gaps in the number sequence belong to old bugs which were
- eliminated.)
-
2:
DEFSTRUCT should almost certainly overwrite the old LAYOUT information
instead of just punting when a contradictory structure definition
- is loaded.
+ is loaded. As it is, if you redefine DEFSTRUCTs in a way which
+ changes their layout, you probably have to rebuild your entire
+ 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:
It should cause a STYLE-WARNING, not a full WARNING, when a structure
very good when the stream argument has the wrong type, because
the operation tries to fall through to Gray stream code, and then
dies because it's undefined. E.g.
- (PRINT-UNREADABLE-OBJECT (*STANDARD-OUTPUT* 1))
+ (PRINT-UNREADABLE-OBJECT (*STANDARD-OUTPUT* 1)) ..)
gives the error message
error in SB-KERNEL::UNDEFINED-SYMBOL-ERROR-HANDLER:
The function SB-IMPL::STREAM-WRITE-STRING is undefined.
DTC's recommended workaround from the mailing list 3 Mar 2000:
(setf (pcl::find-class 'ccc1) (pcl::find-class 'ccc))
-21:
- There's probably a bug in the compiler handling of special variables
- in closures, inherited from the CMU CL code, as reported on the
- CMU CL mailing list. There's a patch for this on the CMU CL
- mailing list too:
- Message-ID: <38C8E188.A1E38B5E@jeack.com.au>
- Date: Fri, 10 Mar 2000 22:50:32 +1100
- From: "Douglas T. Crosher" <dtc@jeack.com.au>
-
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
(FAIL 12)
then requesting a BACKTRACE at the debugger prompt gives no information
about where in the user program the problem occurred.
+
+62:
+ The compiler is supposed to do type inference well enough that
+ the declaration in
+ (TYPECASE X
+ ((SIMPLE-ARRAY SINGLE-FLOAT)
+ (LOCALLY
+ (DECLARE (TYPE (SIMPLE-ARRAY SINGLE-FLOAT) X))
+ ..))
+ ..)
+ is redundant. However, as reported by Juan Jose Garcia Ripoll for
+ CMU CL, it sometimes doesn't. Adding declarations is a pretty good
+ workaround for the problem for now, but can't be done by the TYPECASE
+ macros themselves, since it's too hard for the macro to detect
+ assignments to the variable within the clause.
+ Note: The compiler *is* smart enough to do the type inference in
+ many cases. This case, derived from a couple of MACROEXPAND-1
+ calls on Ripoll's original test case,
+ (DEFUN NEGMAT (A)
+ (DECLARE (OPTIMIZE SPEED (SAFETY 0)))
+ (COND ((TYPEP A '(SIMPLE-ARRAY SINGLE-FLOAT)) NIL
+ (LET ((LENGTH (ARRAY-TOTAL-SIZE A)))
+ (LET ((I 0) (G2554 LENGTH))
+ (DECLARE (TYPE REAL G2554) (TYPE REAL I))
+ (TAGBODY
+ SB-LOOP::NEXT-LOOP
+ (WHEN (>= I G2554) (GO SB-LOOP::END-LOOP))
+ (SETF (ROW-MAJOR-AREF A I) (- (ROW-MAJOR-AREF A I)))
+ (GO SB-LOOP::NEXT-LOOP)
+ SB-LOOP::END-LOOP))))))
+ demonstrates the problem; but the problem goes away if the TAGBODY
+ and GO forms are removed (leaving the SETF in ordinary, non-looping
+ code), or if the TAGBODY and GO forms are retained, but the
+ assigned value becomes 0.0 instead of (- (ROW-MAJOR-AREF A I)).
+
+
+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.
projects / sbcl.git / blobdiff