DIP: add Bit Fields

[Timon Gehr]

On 3/7/24 20:42, Walter Bright wrote:
> 
> I.e. the layout is implementation-defined. That's correct. But in 
> reality, it is fixed. There is no way that gcc on Linux is *ever* going 
> to change the bit field layout, because it would break legions of 
> existing code. It is cast in concrete, and is as immutable as it gets. 
> The same for Microsoft C.
> 
> Furthermore, if you use `int` as the base type for bit fields, the 
> layouts are all the same in all the C compilers I've encountered. For 
> practical purposes, it is defined.
> 
> If you are still concerned about the layout, like you want a portable 
> file format, don't use bit fields. Use std.bitmanip.

Well, that's kind of a foot gun. Portable by default is better.