On Fri, 2 May 2014, Electron wrote:

>
> Hello!
>
> a is a signed int and contains -100
> b is an unsigned int and contains 500
>
> a<b returns FALSE!!
>
> Why on earth? :P
>
> I can cast b to signed int and get the correct results,
> but leaving as is instead the result surprises me a lot,
> as I have no idea why -100<500 should be false, it's like
> if the compiler casts a to an unsigned type automatically
> (and this was clearly not requested by the programmer).
>
> If we keep them as they are, i.e. the first signed and the
> second unsigned, then why should a<b return false???
>
> This is very confusing really.
>
> Now I have to correct all of my code, looking for
> comparisons between signed and unsigned ints, and cast
> both variables to the type I mean. :-/
>
> Is there any other situation I have to be careful about
> when mixing signed and unsigned types?
>
> Please do not reply the obvious "generically the use of
> unsigned types is not adviceable, why don't you stick
> with only signed types? you will be much safer". THANKS.
>
> Cheers,
> Mario

You should switch to a language that deals with mixed signed / unsigned=20
comparisons correctly :-)

XCSB does it correctly. it returns true for -1 < 255 (8 bit signed < 8 bit=
=20
unsigned).

Cheers
Sergio
--=20
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