Adding UNION/MAP -- Feedback and tips pls!

[N.M. Maclaren]

On Mar 6 2013, Andrew Pinski wrote:
>
>Except GCC implements C's unions as allowing to do type punning as an
>extension and as far as GCC is concerned that is not going to change
>any time soon.
>This is a documented exception to the aliasing/type punning rules.

The problem is that this is worse than type punning, because it also
allows the preservation of data.  Does the extension guarantee that,
or would it need a change to at least the documentation?


Regards,
Nick Maclaren.