diff --git a/sdk/include/ndk/ketypes.h b/sdk/include/ndk/ketypes.h
index bd9409d5d26..0fba8d3455f 100644
--- a/sdk/include/ndk/ketypes.h
+++ b/sdk/include/ndk/ketypes.h
@@ -221,8 +221,8 @@ typedef CCHAR KPROCESSOR_MODE;
 //
 #define SharedUserData                  ((KUSER_SHARED_DATA *)USER_SHARED_DATA)
 
-/* Macros for user-mode run-time checks of X86 system architecture */
 #ifdef _X86_
+/* Macros for user-mode run-time checks of X86 system architecture */
 
 #ifndef IsNEC_98
 #define IsNEC_98     (SharedUserData->AlternativeArchitecture == NEC98x86)
@@ -242,8 +242,27 @@ typedef CCHAR KPROCESSOR_MODE;
 #define SetNotNEC_98
 #endif
 
+#else // !_X86_
+/* Correctly define these run-time definitions for non X86 machines */
+
+#ifndef IsNEC_98
+#define IsNEC_98 (FALSE)
 #endif
 
+#ifndef IsNotNEC_98
+#define IsNotNEC_98 (TRUE)
+#endif
+
+#ifndef SetNEC_98
+#define SetNEC_98
+#endif
+
+#ifndef SetNotNEC_98
+#define SetNotNEC_98
+#endif
+
+#endif // _X86_
+
 //
 // Maximum WOW64 Entries in KUSER_SHARED_DATA
 //