int always 32 bits on all platforms?

[Jason House]

AJ Wrote:

> 
> "BCS" <none at anon.com> wrote in message 
> news:a6268ffbadb8cc20772570e4f0 at news.digitalmars.com...
> > Hello aJ,
> >
> >> How can/does D guarantee that "int" will always be 32 bits on all
> >> platforms? Does this mean that D won't work on some platforms?
> >
> >
> > D is not built for 8 or 16 bit systems. However 32 bit math can be done on 
> > a 16 bit CPU, it's just slow. In the other direction, 32 bit math (and 16 
> > and 8 bit) can be done on a 64 bit CPU so that's not a problem.
> 
> I wasn't thinking about math issues, but rather struct field 
> alignment/portability, and platform alignment requirements for basic types, 
> issues. I'm guessing that it is all worked out by the compiler, so that 
> makes the development of a compiler more difficult, if so, but how much more 
> difficult? A simple example or description of how this is done would really 
> be great. (BTW, this is definitely an area where I would approve of more 
> language implementation complexity for the great strides in programming 
> efficiency (and fun!) it gives).
> 
> 
> 

In D, both type size and alignment have the same defaults on all platforms. If desired, alignment can be explicitly controlled with the align attribute. Similarly, use of specific types control sizes.