Used in
- PCI_SECONDARY_EXTENSION, _EVENT_COUNTER, _HEAP_SUBSEGMENT, _HEAP_USERDATA_HEADER, _KNODE, _KPRCB, _KPROCESS, _KTHREAD, _LPCP_MESSAGE, _MMPFN, _PCI_FDO_EXTENSION, _PCI_PDO_EXTENSION, _PI_BUS_EXTENSION, _POP_DEVICE_POWER_IRP, _SINGLE_LIST_ENTRY, _SLIST_HEADER, _VI_POOL_ENTRY, _VI_POOL_PAGE_HEADER, _WMI_BUFFER_HEADER