Why is 64-bit dmd not built as part of the Windows release?

[Vladimir Panteleev]

On Wednesday, 23 May 2018 at 17:35:28 UTC, Dlang User wrote:
> I too am looking for 64-bit on Windows 10.  Not just DMD but 
> ideally everything.
>
> When I try the command exactly as above, or a slightly modified 
> version (on a second run show after this run), I hit an error 
> on my machine:
>
> Internal error: dmd\backend\cod3.c 6830

Hmm, that looks like a DMD bug/regression. I think that should 
have been caught by the auto-tester. In any case, try adding 
--model=64 to your command to also build a 64-bit Phobos, as that 
seems to be what you're after anyway. You could also try 
specifying a different (newer?) host DMD version with e.g. `-c 
build.components.dmd.bootstrap.ver=v2.075.0`.