_HEAP_FREE_ENTRY_EXTRA

Windows 10 1703 Redstone 2 (Creators Update) x86
Windows 10 1709 Redstone 3 (Fall Creators Update) x86
Windows 10 1803 Redstone 4 (Spring Creators Update) x86
//0x4 bytes (sizeof)
struct _HEAP_FREE_ENTRY_EXTRA
{
    USHORT TagIndex;                                                        //0x0
    USHORT FreeBackTraceIndex;                                              //0x2
};