D equivalent of C++ reinterpret cast?

[Juanjo Alvarez]

On Sun, 19 Sep 2010 20:07:38 -0400, bearophile 
<bearophileHUGS at lycos.com> wrote:
> C standard say that's not safe. You can force that to be safe in 
C-GCC if you explicitly disable a compiler optimization. I think D 
docs don't say anything about this. And Walter has said that 
regarding such things D acts as C. So I am not sure that will be safe 
in future D.

Unions are not allowed in SafeD, so I guess they are considered 
unsafe in D.