SIMD on Windows

[Rainer Schuetze]

On 23.06.2013 21:55, Michael wrote:
> Cool)))
>
> Any chances to see it [coff32] in official build?
>

Let's see if Walter approves.

There is one maybe disruptive change: with two different C runtimes 
available for Win32, versioning on Win32/Win64 no longer works. I added 
versions CRuntime_DigitalMars and CRuntime_Microsoft (and CRuntime_GNU 
for anything else), and adapting to this makes most of the changes in 
druntime and phobos.