Re: CONSTRAINT_ERROR - why?

[Alfred Hilscher <Alfred.Hilscher@t-online.de>]

Robert A Duff schrieb:
> 
> "James S. Rogers" <jimmaureenrogers@worldnet.att.net> writes:
> 
> > "Alfred Hilscher" <Alfred.Hilscher@t-online.de> wrote in message
> > news:3DFB7841.F898C02@t-online.de...
> > > This program raises exception CONSTRAINT_ERROR for the second
> > > assignment. It happens with GNAT 3.13p and 3.14p (on windows).
> > >
> > > Can someone explain why? Is this a compiler error or do I misunderstand
> > > something?
> > >
> > > I would expect that the computation is done first and then the result
> > > (33 which is successfully assigned the statement before) is assigned.
> > > But it seems that the size (=264) is assigned before the division is
> > > executed.
> 
> The 'Size is implicitly converted to BYTE, and then the "/" operator of
> type BYTE is used.  You want to do the division in, say, Integer,
> and then explicitly convert to BYTE, like:
> 
>     ... := BYTE(Integer'(Fac_Conf_Struct'Size / 8));

Shouldn`t the conversion take place _after_ the computation? First
compute ('size /8) as universal_integer and then adopt (for the
assignment only) to the type of the right side?