[Gambas-user] Possible error when doing math on bytes

[Jussi Lahtinen]

Why do you use bytes in that code? You cannot trust in that approach anyway.

Jussi

On Wed, Jan 4, 2023 at 12:48 AM Brian G <brian at westwoodsvcs.com> wrote:

> A lot of my applications no longer run,
>
> And bad new, it reports error even if fast unsafe in my apps
>
> How do i just turn this off permanently, It is very bad news!
>
>
> "Failure is the key to success;
>  each mistake teaches us something"  .. Morihei Ueshiba
> Brian G
>
> ----- On Jan 3, 2023, at 2:40 PM, Benoit Minisini
> benoit.minisini at gambas-basic.org wrote:
>
> > Le 03/01/2023 à 23:08, Brian G a écrit :
> >> When I do math on bytes I get an overflow now when  the value of the
> >> byte goes negative
> >> example:
> >>   dim a as byte = 0
> >>   dim b as byte = 24
> >>   dim result as byte = a - b
> >>
> >> This causes an overflow error, where in the past it was just a negative
> >> number.
> >> Is this a bug or a new undocumented feature?
> >>
> >
> > Overflows were ignored before, as it is usually the case in C programs,
> > even if the behaviour of overflows is unspecified. It's for speed
> > reasons, or to make hacking easier, I dunno.
> >
> > So I decided to detect them, for a small performance penalty.
> >
> > The overflow checks are only disabled on 'Fast Unsafe' functions.
> >
> > Regards,
> >
> > --
> > Benoît Minisini.
> >
> >
> > ----[ http://gambaswiki.org/wiki/doc/netiquette ]----
>
> ----[ http://gambaswiki.org/wiki/doc/netiquette ]----
>
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