Does -0.5 fit an unsigned when truncated to an integer?

[Vincent Lefevre]

On 2013-03-19 22:11:31 +0100, bodrato at mail.dm.unipi.it wrote:
> Ciao,
> 
> Il Mar, 19 Marzo 2013 6:39 pm, Torbjorn Granlund ha scritto:
> > After some  thought, I support I agree.
> 
> >   _fits_uTYPE require the range 0 <= x < uTYPE_MAX + 1
> >
> > Which deviates.
> 
> One we agree, it is simple to obtain the desired range, swaping two
> conditions...

It is also the choice made by MPFR (fixed in the trunk only for the
moment). It is also analogous to the conventional IEEE 754 rounding:
if an exact result x (real number to be rounded) is larger than the
maximum representable FP number, one gets an overflow only when its
rounding in an unbounded exponent range would yield an out-of-range
result in the target format.

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Vincent Lefèvre <vincent at vinc17.net> - Web: <http://www.vinc17.net/>
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