[dchest]

What a coincidence, I was just browsing Microsoft's Go fork (for FIPS compatibility, basically replacing Go crypto with OpenSSL and whatever API Windows has, just like there's a Google's fork that uses BoringSSL), and found this patch:

https://github.com/microsoft/go/blob/microsoft/main/patches/...

Upstream Go tricks Windows into enabling long path support by setting an undocumented flag in the PEB. The Microsoft Go fork can't use undocumented APIs, so this commit removes the hack.

So, even if they fork something, they have to strictly follow this guideline and remove undocumented API usage. I wonder if this only applies to Windows APIs though.