Source?

(Are you referring to the use of software like Colinux and Andlinux? Those only worked on 32-bit systems last time I checked...)

I haven't been involved with Wine in a long time but the Wine test suite itself is regularly run on Windows:

https://test.winehq.org/data/

Here's an admittedly very old article by Dan Kegel on how to compile it on Windows: http://www.kegel.com/wine/wow.html

But yeah, I don't think it's explicitly supported since it's not their target market :) Codeweavers' focus is running Windows apps on Mac and Linux (Crossover - go support them! https://www.codeweavers.com/)

Edit: It looks like they completely dropped support for it as I can't find any of the old articles anymore; Seems it only supports mingw setup now. https://wiki.winehq.org/Cygwin_and_More

What's the difference between Wine, Crossover and PlayOnLinux?

Crossover is a commercial version of Wine which includes a bunch of extra hacks for popular applications. It comes with support. It's how the Wine project pays salaries.

PlayOnLinux is a Wine wrapper which has preset configurations (best known working wine version and dll overrides) for a ton of popular games/software. Think of it like a virtualenv on steroids.