Is there any reason why arithmetic operation on shorts and bytes return int?

[Walter Bright]

On 12/12/2012 10:25 AM, Jonathan M Davis wrote:
> If alias this isn't do an implict conversion, then there's a bug in alias
> this. That's how implict conversion is done in D, and it's the whole point
> of alias this.

And it does, as I relied on this to do the halffloat implementation.