diff --git a/reactos/include/psdk/intrin_x86.h b/reactos/include/psdk/intrin_x86.h
index b528735cb75..3873ad4ed2f 100644
--- a/reactos/include/psdk/intrin_x86.h
+++ b/reactos/include/psdk/intrin_x86.h
@@ -104,11 +104,6 @@ static __inline__ __attribute__((always_inline)) long _InterlockedCompareExchang
 	return __sync_val_compare_and_swap(Destination, Comperand, Exchange);
 }
 
-static __inline__ __attribute__((always_inline)) long long _InterlockedCompareExchange64(volatile long long * const Destination, const long long Exchange, const long long Comperand)
-{
-	return __sync_val_compare_and_swap(Destination, Comperand, Exchange);
-}
-
 static __inline__ __attribute__((always_inline)) void * _InterlockedCompareExchangePointer(void * volatile * const Destination, void * const Exchange, void * const Comperand)
 {
 	return __sync_val_compare_and_swap(Destination, Comperand, Exchange);
@@ -236,23 +231,6 @@ static __inline__ __attribute__((always_inline)) long _InterlockedCompareExchang
 	return retval;
 }
 
-static __inline__ __attribute__((always_inline)) long long _InterlockedCompareExchange64(volatile long long * const Destination, const long long Exchange, const long long Comperand)
-{
-	long long retval = Comperand;
-
-	__asm__
-	(
-		"cmpxchg8b %[Destination]" :
-		[retval] "+A" (retval) :
-			[Destination] "m" (*Destination),
-			"b" ((unsigned long)((Exchange >>  0) & 0xFFFFFFFF)),
-			"c" ((unsigned long)((Exchange >> 32) & 0xFFFFFFFF)) :
-		"memory"
-	);
-
-	return retval;
-}
-
 static __inline__ __attribute__((always_inline)) void * _InterlockedCompareExchangePointer(void * volatile * const Destination, void * const Exchange, void * const Comperand)
 {
 	void * retval = (void *)Comperand;
@@ -443,6 +421,34 @@ static __inline__ __attribute__((always_inline)) long _InterlockedXor(volatile l
 
 #endif
 
+#if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) > 40100 && defined(__x86_64__)
+
+static __inline__ __attribute__((always_inline)) long long _InterlockedCompareExchange64(volatile long long * const Destination, const long long Exchange, const long long Comperand)
+{
+	return __sync_val_compare_and_swap(Destination, Comperand, Exchange);
+}
+
+#else
+
+static __inline__ __attribute__((always_inline)) long long _InterlockedCompareExchange64(volatile long long * const Destination, const long long Exchange, const long long Comperand)
+{
+	long long retval = Comperand;
+
+	__asm__
+	(
+		"lock; cmpxchg8b %[Destination]" :
+		[retval] "+A" (retval) :
+			[Destination] "m" (*Destination),
+			"b" ((unsigned long)((Exchange >>  0) & 0xFFFFFFFF)),
+			"c" ((unsigned long)((Exchange >> 32) & 0xFFFFFFFF)) :
+		"memory"
+	);
+
+	return retval;
+}
+
+#endif
+
 static __inline__ __attribute__((always_inline)) long _InterlockedAddLargeStatistic(volatile long long * const Addend, const long Value)
 {
 	__asm__