diff --git a/reactos/include/ddk/winddk.h b/reactos/include/ddk/winddk.h
index 32b5f5cbea1..0ecca592a40 100644
--- a/reactos/include/ddk/winddk.h
+++ b/reactos/include/ddk/winddk.h
@@ -5642,11 +5642,26 @@ KeTestSpinLock(
 
 #if defined (_X86_)
 
+#if defined(WIN9X_COMPAT_SPINLOCK)
+
 NTKERNELAPI
 VOID
 NTAPI
 KeInitializeSpinLock(
-  IN PKSPIN_LOCK  SpinLock);
+    IN PKSPIN_LOCK SpinLock
+);
+
+#else
+
+FORCEINLINE
+VOID
+KeInitializeSpinLock(IN PKSPIN_LOCK SpinLock)
+{
+    /* Clear the lock */
+    *SpinLock = 0;
+}
+
+#endif
 
 NTHALAPI
 KIRQL
diff --git a/reactos/ntoskrnl/ke/spinlock.c b/reactos/ntoskrnl/ke/spinlock.c
index 7e63026db3b..8d5c72c641f 100644
--- a/reactos/ntoskrnl/ke/spinlock.c
+++ b/reactos/ntoskrnl/ke/spinlock.c
@@ -123,7 +123,7 @@ KeReleaseInterruptSpinLock(IN PKINTERRUPT Interrupt,
  */
 VOID
 NTAPI
-KeInitializeSpinLock(IN PKSPIN_LOCK SpinLock)
+_KeInitializeSpinLock(IN PKSPIN_LOCK SpinLock)
 {
     /* Clear it */
     *SpinLock = 0;
diff --git a/reactos/ntoskrnl/ntoskrnl-generic.rbuild b/reactos/ntoskrnl/ntoskrnl-generic.rbuild
index 15dc82e4043..3ea37627fd3 100644
--- a/reactos/ntoskrnl/ntoskrnl-generic.rbuild
+++ b/reactos/ntoskrnl/ntoskrnl-generic.rbuild
@@ -7,7 +7,6 @@
 	<define name="_NTOSKRNL_" />
 	<define name="_NTSYSTEM_" />
 	<define name="__NO_CTYPE_INLINES" />
-	<define name="WIN9X_COMPAT_SPINLOCK" />
 	<define name="_IN_KERNEL_" />
 	<if property="_WINKD_" value="1">
 		<define name="_WINKD_" />
diff --git a/reactos/ntoskrnl/ntoskrnl.pspec b/reactos/ntoskrnl/ntoskrnl.pspec
index b68be242fb2..d5c61bf63a4 100644
--- a/reactos/ntoskrnl/ntoskrnl.pspec
+++ b/reactos/ntoskrnl/ntoskrnl.pspec
@@ -599,7 +599,7 @@
 @ stdcall KeInitializeMutex(ptr long)
 @ stdcall KeInitializeQueue(ptr long)
 @ stdcall KeInitializeSemaphore(ptr long long)
-@ stdcall KeInitializeSpinLock(ptr)
+@ stdcall KeInitializeSpinLock(ptr) _KeInitializeSpinLock
 @ stdcall KeInitializeThreadedDpc(ptr ptr ptr)
 @ stdcall KeInitializeTimer(ptr)
 @ stdcall KeInitializeTimerEx(ptr long)