So! Intel TBB (ok, new name is "UXL Foundation oneTBB") header files were including whole <windows.h> just to get a "void SwitchToThread()", more or less.

Well, not anymore, I fix0red that https://github.com/uxlfoundation/oneTBB/pull/1932 (a bug report to do that was open for 5 years lol)