http://bugs.winehq.org/show_bug.cgi?id=58420
--- Comment #2 from pipcet@protonmail.com --- For what it's worth, I feel quite strongly that Linux should allow "hiding" XCR0 features on a per-process basis. That would allow Wine to work around this bug on the Linux/Wine side of things, and run unfixed Cygwin software on new CPUs without a reboot (and a reduced feature set in the rebooted system).
I suggested that, and the suggestion was rejected.
This means that Wine will now move further away from bug-for-bug compatibility with Windows whenever a new CPU feature is introduced (Linux would enable it for everyone, and even if there is an option to disable it, that would necessarily require a reboot of the Linux system).
I may be overestimating how important such compatibility is to the Wine developers, but if I'm not, our best remaining option would be to make Wine use virtualization instead of hoping to be able to run a Windows program as a Linux process directly; that wouldn't make Wine an emulator, it would merely mean that we trap certain instructions to hide CPU features which Windows doesn't enable or which work differently on Linux and Windows.