Since VS 16.11 the compiler sometimes emits calls to _RTC_UninitUse, when parts of a bitfield are initialized (See https://developercommunity.visualstudio.com/t/Broken-runtime-checks-with-CL-19293013/1503629). Fix this by using an ULONG instead of a bitfield.
Note: The structure uses a 24 bit bitfield plus an UCHAR, which is supposed to form a 32 bit field, but that doesn't work anyway.