How to compile for Win64 with Visual D? Optlink error?

[Nicholas Wilson]

On Tuesday, 19 September 2017 at 11:47:00 UTC, Timothy Foster 
wrote:
> I'm trying to compile my project as a Win64 application but 
> this is happening:
>
> Building C:\Users\me\test\test.exe...
> OPTLINK (R) for Win32  Release 8.00.17
> Copyright (C) Digital Mars 1989-2013  All rights reserved.
> http://www.digitalmars.com/ctg/optlink.html
> OPTLINK : Warning 183: Extension not .RES : 
> obj\debug\dummy\test\..\source\c.obj
> obj\debug\dummy\test\..\source\b.obj(1) : Error 52: .DEF Syntax 
> Error
> d†š
öñÀY$@
>
> ^
> Building C:\Users\me\test\test.exe failed!
>
>
> I'm on a Win64 machine and compiling Win32 works fine. I'm 
> using Visual Studio 17 Community with Visual D. DMD is up to 
> date as is Visual D.
>
> I added a x64 "solution platform" to the configuration manager 
> which added a -m64 flag to my linker options. I'm not sure what 
> else I'm meant to do to get it to compile as x64?

I'm not sure why its trying to use opt link for 64-bit, the 
linker banner gives a hint:
OPTLINK (R) for _Win32_.

64 bit should use MS's linker, is -m64 only passed to the linker 
but not the compiler?