diff --git a/sdk/xtdk/amd64/ketypes.h b/sdk/xtdk/amd64/ketypes.h
index 1d1b01d..0dce5be 100644
--- a/sdk/xtdk/amd64/ketypes.h
+++ b/sdk/xtdk/amd64/ketypes.h
@@ -293,7 +293,7 @@ typedef struct _KTSS
     ULONG64 Reserved1;
     USHORT Reserved2;
     USHORT IoMapBase;
-} PACK KTSS, *PKTSS;
+} PACKED KTSS, *PKTSS;
 
 /* Exception frame definition */
 typedef struct _KEXCEPTION_FRAME
diff --git a/sdk/xtdk/hltypes.h b/sdk/xtdk/hltypes.h
index 47b7843..57af4ec 100644
--- a/sdk/xtdk/hltypes.h
+++ b/sdk/xtdk/hltypes.h
@@ -164,7 +164,7 @@ typedef struct _ACPI_DESCRIPTION_HEADER
     ULONG OemRevision;
     UCHAR CreatorID[4];
     ULONG CreatorRev;
-} PACK ACPI_DESCRIPTION_HEADER, *PACPI_DESCRIPTION_HEADER;
+} PACKED ACPI_DESCRIPTION_HEADER, *PACPI_DESCRIPTION_HEADER;
 
 /* ACPI Root System Description Table Pointer structure */
 typedef struct _ACPI_RSDP
@@ -178,14 +178,14 @@ typedef struct _ACPI_RSDP
     ULONGLONG XsdtAddress;
     UCHAR XChecksum;
     UCHAR Reserved[3];
-} PACK ACPI_RSDP, *PACPI_RSDP;
+} PACKED ACPI_RSDP, *PACPI_RSDP;
 
 /* ACPI Root System Description Table structure */
 typedef struct _ACPI_RSDT
 {
     ACPI_DESCRIPTION_HEADER Header;
     UCHAR Entries[];
-} PACK ACPI_RSDT, *PACPI_RSDT;
+} PACKED ACPI_RSDT, *PACPI_RSDT;
 
 /* Serial (COM) port initial state */
 typedef struct _CPPORT
diff --git a/sdk/xtdk/xtdefs.h b/sdk/xtdk/xtdefs.h
index 941fa4b..3403ee1 100644
--- a/sdk/xtdk/xtdefs.h
+++ b/sdk/xtdk/xtdefs.h
@@ -16,6 +16,7 @@
 #define XTAPI                                  __stdcall
 #define XTCDECL                                __cdecl
 #define XTFASTCALL                             __fastcall
+#define XTVECTORCALL                           __vectorcall
 #define XTINLINE                               __inline
 #define XTASSEMBLY                             __attribute__((naked))
 #define XTINTERRUPT                            __attribute__((interrupt))
@@ -54,7 +55,7 @@
 
 /* Preprocessor macros for defining an additional compiler attributes */
 #define ALIGN(Alignment)                       __attribute__((aligned(Alignment)))
-#define PACK                                   __attribute__((packed))
+#define PACKED                                 __attribute__((packed))
 #define SEGMENT(Segment)                       __attribute__((section(Segment)))
 #define USED                                   __attribute__((__used__))