fx* does not check for overflow

[leppie]

Not sure if this is classified as a bug. The behaviour is not defined in R6RS (is it part of the IEEE floating point spec maybe?). There also seems to be inconsistency between fx*/fx+ and fx-/fx/ expected results in terms of exceptions and the 'correct' vs the 'mathematically correct' answer.

> (fx* 429496728 2)
-214748368
> (fx+ 429496728 429496728)
Unhandled exception
 Condition components:
   1. &assertion
   2. &who: fx+
   3. &message: "overflow when adding numbers"
   4. &irritants: (429496728 429496728)

[Abdulaziz Ghuloum (aghuloum)]

Will fix. Thanks.

[leppie (leppie)]

Ignore the IEEE floating point stuff I mentioned (brain lapse ;p).

[Abdulaziz Ghuloum (aghuloum)]

fx* now checks for overflow (revision 1380).

[Abdulaziz Ghuloum (aghuloum)]

fx- now checks for overflow (revision 1381)

[Abdulaziz Ghuloum (aghuloum)]

Is that it?

[leppie (leppie)]

Nope :) found more. I think there is only that one case in negate, but it seems Ikarus does not handle 'fx-negate' (yet).

Ikarus:
> (fx- (greatest-fixnum))
Unhandled exception
 Condition components:
   1. &assertion
   2. &who: apply
   3. &message: "incorrect number of arguments"
   4. &irritants: (1 #<procedure fx->)

IronScheme:
> (fx- (greatest-fixnum))
-2147483647
> (fx- (least-fixnum))
&assertion
&who: fx-
&message: arithmetic overflow
&irritants: (-2147483648)

[Abdulaziz Ghuloum (aghuloum)]

Missed that. Thanks. It's now fixed in 1382.