diff --git a/reactos/hal/halx86/mp/spinlock.c b/reactos/hal/halx86/mp/spinlock.c
index 824220792dd..0893ad83a98 100644
--- a/reactos/hal/halx86/mp/spinlock.c
+++ b/reactos/hal/halx86/mp/spinlock.c
@@ -176,6 +176,17 @@ KeAcquireQueuedSpinLock(IN PKLOCK_QUEUE_HANDLE LockHandle)
    return 0;
 }
 
+/*
+ * @unimplemented
+ */
+KIRQL
+FASTCALL
+KeAcquireQueuedSpinLockRaiseToSynch(IN KSPIN_LOCK_QUEUE_NUMBER LockNumber)
+{
+    UNIMPLEMENTED;
+    return 0;
+}
+
 /*
  * @unimplemented
  */