#endif
#if defined(_TARGET_AMD64_) || defined(_TARGET_ARM64_)
+#ifndef _TARGET_64BIT_
#define _TARGET_64BIT_
-#endif
+#endif // _TARGET_64BIT_
+#endif // defined(_TARGET_AMD64_) || defined(_TARGET_ARM64_)
+
+#ifdef _TARGET_64BIT_
+#ifdef _TARGET_X86_
+#error Cannot define both _TARGET_X86_ and _TARGET_64BIT_
+#endif // _TARGET_X86_
+#ifdef _TARGET_ARM_
+#error Cannot define both _TARGET_ARM_ and _TARGET_64BIT_
+#endif // _TARGET_ARM_
+#endif // _TARGET_64BIT_
#if defined(_TARGET_X86_) || defined(_TARGET_AMD64_)
#define _TARGET_XARCH_