Making a forward declaration of a C symbol defined in another CU

[Dennis]

On Thursday, 20 December 2018 at 08:31:53 UTC, Alexander Nicholi 
wrote:
> Oh, that works fine, thanks. I thought I already did that with 
> the extern (C), but I guess that's a different kind of extern 
> isn't it

Indeed, extern(C) only changes the mangled name and calling 
convention, it doesn't also mark variables as extern.