typedef struct _HEAP_FAILURE_INFORMATION
{
     ULONG Version;
     ULONG StructureSize;
     HEAP_FAILURE_TYPE FailureType;
     PVOID HeapAddress;
     PVOID Address;
     PVOID Param1;
     PVOID Param2;
     PVOID Param3;
     PHEAP_ENTRY PreviousBlock;
     PHEAP_ENTRY NextBlock;
     HEAP_ENTRY ExpectedEncodedEntry;
     HEAP_ENTRY ExpectedDecodedEntry;
     VOID * StackTrace[32];
} HEAP_FAILURE_INFORMATION, *PHEAP_FAILURE_INFORMATION;

Windows Vista Kernel Structures