First Draft: Bit Fields

[Richard (Rikki) Andrew Cattermole]

"gdc/lcd are lumped together because they produce identical results on 
the same platform."

s/lcd/ldc/

No mention of alignment, total size or the offset.

Needs to mention atomics as not being supported.

No trait to detect a bit field (if its an alias, or by name), nor get 
its size. Kinda required, enough other things in the language can appear 
via an alias sequence or by allMembers that are not able to be taken as 
a pointer of.

The ability to take an alias via getMember needs to be considered if its 
valid to do so.

No mention of tupleof either, what happens there?

No motivation for not including a D layout for it, instead of forcing 
everyone into an unpredictable layout that the system C compiler might 
be using. Moving us off the library type and into a language defined one 
that is predictable is quite attractive so there needs to be an argument 
against this.

Also both the post and its subject do not match the guidelines for this 
forum. So I'm half wondering if it's even worth writing this post 
knowing that Mike could delete it.

https://github.com/dlang/DIPs/blob/master/docs/guidelines-forums.md#dip-development