Custom Query (1030 matches)

The sqrt, log and atan functions are failing over significant portions of their domain (particularly for rational or complex rational arguments), even when it is entirely reasonable that a good result should be returned. Some typical examples are:

(sqrt (expt 10 47)) => 3.1622778E+23 ;CCL errors
(sqrt (/ (expt 10 47) 3)) => 1.8257418E+23 ;CCL errors
(sqrt (complex (expt 10 46) (expt 10 47))) => #C(2.3505187E+23 2.12719E+23) ;CCL errors
(sqrt (complex most-positive-short-float most-positive-short-float)) => #C(2.0267142E+19 8.394926E+18) ;CCL errors

(log (expt 10 -66)) => -151.97063 ;CCL errors
(log (- (expt 10 66))) => #C(151.97063 3.1415927) ;CCL returns wrong type (double, not single)
(log (complex (expt 10 65) (expt 10 66))) => #C(151.9756 1.4711276) ;CCL errors
(log (complex (expt 10 -65) (expt 10 -66))) => #C(-149.66307 0.09966865) ;CCL errors
(log 8.0d0 2) => 3.0D0 ;CCL returns wildly inaccurate result
(log #C(0.0 1.0) 0) => #C(0.0 0.0) ;CCL returns wrong type (integer)

(atan (expt 10 46) (expt 10 47)) => 0.09966865 ;CCL errors
(atan (expt 10 -46) (expt 10 -47)) => 1.4711276 ;CCL returns zero

I'm attaching a file that demonstrates how these could all be fixed by making changes to CCL's sqrt, log, log-e and atan functions (but the changes may not be implemented in the most efficient way). Making these fixes would also have a knock-on effect and correct dependent infelicities in both the arg and phase functions (which aren't noted above).

The definition of TYPECASE, ETYPECASE and CTYPECASE in the standard (CLHS §5.3) allows that there be multiple clauses specifying a matching type. If a clause is completely shadowed by earlier clauses, the compiler may issue a warning. The type of the warning is explicitly mentioned to be STYLE-WARNING. The exact wording is as follows:

The compiler may choose to issue a warning of type style-warning if a clause will never be selected because it is completely shadowed by earlier clauses.

However, CCL issues a SIMPLE-WARNING in such situations, e. g.:

(block nil
  (handler-bind ((warning (lambda (w) (return (type-of w)))))
    (macroexpand '(typecase nr
                    (long-float #\L) 
                    (double-float #\D)
                    (short-float #\S)
                    (t #\E)))))
⇒ SIMPLE-WARNING

Which, I believe, contradicts the above disposition of the standard. One consequence is that, with ASDF, such a warning issued during the compilation of a file makes COMPILE-OP fail, signalling an error where, in fact, there should be none.

I'm trying to run CCL on an Acer Iconia A500. That's an Android tablet but I run Debian (Squeeze) in a chroot environment. CCL starts but backtraces don't seem to work:

helmut@iconia:~/lisp/ccl$ uname -a
Linux iconia 2.6.36.3 #3 SMP PREEMPT Fri May 13 00:20:42 CST 2011 armv7l GNU/Linux
helmut@iconia:~/lisp/ccl$ rlwrap ./armcl
Welcome to Clozure Common Lisp Version 1.7-dev-r14869  (LinuxARM32)!
? (/ 1 0)
> Error: DIVISION-BY-ZERO detected
>        performing / on (1 0)
> While executing: CCL::%FIXNUM-TRUNCATE, in process listener(1).
> Type :POP to abort, :R for a list of available restarts.
> Type :? for other options.
1 > b
Origin 270332994 is not in the stack of NIL
1 >

Is this a known problem of the ARM port? Has it something to do with the chroot tricks? Perhaps because /proc doesn't not working quite correclty with chroot?