http://bugs.winehq.org/show_bug.cgi?id=58751
--- Comment #9 from Shmerl shtetldik@gmail.com --- I checked, ntsync.h found in linux-libc-dev and in linux-headers-6.16.9+deb14-common is exactly the same.
So I assume your build with linux-libc-dev present according to your build depends should produce a good result, so why doesn't it work?
I was testing your forky Wine build with Cyberpunk 2077 with mangohud, and it shows that ntsync is not available which is also demonstrated by bad performance (unlike using my build).
The only extra addition I'm using in tests in vkd3d-proton to make Cyberpunk 2077 work normally.