diff --git a/reactos/include/reactos/typedefs_host.h b/reactos/include/reactos/typedefs_host.h
index be13306961b..564890041cb 100644
--- a/reactos/include/reactos/typedefs_host.h
+++ b/reactos/include/reactos/typedefs_host.h
@@ -52,7 +52,6 @@
 
 typedef void VOID, *PVOID, *HANDLE;
 typedef HANDLE HKEY, *PHKEY;
-typedef long unsigned int SIZE_T, *PSIZE_T;
 typedef unsigned char UCHAR, *PUCHAR, BYTE, *LPBYTE;
 typedef char CHAR, *PCHAR, *PSTR;
 typedef const char CCHAR;
@@ -65,8 +64,9 @@ typedef long long LONGLONG;
 typedef unsigned long long ULONGLONG;
 typedef UCHAR BOOLEAN, *PBOOLEAN;
 typedef int BOOL;
-typedef int W64 LONG_PTR, *PLONG_PTR;
-typedef unsigned int W64 ULONG_PTR, *PULONG_PTR;
+typedef long int W64 LONG_PTR, *PLONG_PTR;
+typedef long unsigned int W64 ULONG_PTR, *PULONG_PTR;
+typedef ULONG_PTR SIZE_T, *PSIZE_T;
 typedef wchar_t WCHAR, *PWCHAR, *PWSTR, *LPWSTR;
 typedef const wchar_t *PCWSTR, *LPCWSTR;
 typedef int NTSTATUS;
diff --git a/reactos/tools/mkhive/reginf.c b/reactos/tools/mkhive/reginf.c
index ca8313b7201..1a567d46d92 100644
--- a/reactos/tools/mkhive/reginf.c
+++ b/reactos/tools/mkhive/reginf.c
@@ -181,7 +181,7 @@ do_reg_operation(
 {
 	CHAR EmptyStr = (CHAR)0;
 	ULONG Type;
-	SIZE_T Size;
+	ULONG Size;
 	LONG Error;
 
 	if (Flags & FLG_ADDREG_DELVAL)  /* deletion */