[FS] IBM-FS-103: Normalization for unary arithmetic affects negative zero

Hello,

     The following is a comment from IBM on the Last Call working draft of 
Formal Semantics.


Section 4.4

The normalization rule for the unary arithmetic operators is problematic 
for values of type xs:float and xs:double.  If the operand of unary minus 
is positive zero, the result produced using the usual IEEE.738 rules for 
arithmetic ought to be negative zero, but the result of the normalized 
operation 0.0-(+0.0) will be positive zero.  Similarly, if the operand of 
unary plus is negative zero, the result ought to be negative zero, but the 
result of the normalized operation 0.0+(-0.0) will be positive zero.

Thanks,

Henry (on behalf of IBM)
------------------------------------------------------------------
Henry Zongaro      Xalan development
IBM SWS Toronto Lab   T/L 969-6044;  Phone +1 905 413-6044
mailto:zongaro@ca.ibm.com

Received on Thursday, 1 April 2004 16:22:10 UTC