diff --git a/reactos/hal/hal/hal.c b/reactos/hal/hal/hal.c
index 5833bc6bace..cb255fc997f 100644
--- a/reactos/hal/hal/hal.c
+++ b/reactos/hal/hal/hal.c
@@ -213,15 +213,12 @@ HalCalibratePerformanceCounter(
 }
 
 
-BOOLEAN
+VOID
 NTAPI
-HalDisableSystemInterrupt(
-  ULONG Vector,
-  KIRQL Irql)
+HalDisableSystemInterrupt(ULONG Vector,
+                          KIRQL Irql)
 {
-  UNIMPLEMENTED;
-
-  return TRUE;
+    UNIMPLEMENTED;
 }
 
 
diff --git a/reactos/hal/halarm/generic/hal.c b/reactos/hal/halarm/generic/hal.c
index 43510df2074..a3d70b88b5f 100644
--- a/reactos/hal/halarm/generic/hal.c
+++ b/reactos/hal/halarm/generic/hal.c
@@ -276,15 +276,12 @@ HalCalibratePerformanceCounter(
 }
 
 
-BOOLEAN
+VOID
 NTAPI
-HalDisableSystemInterrupt(
-  ULONG Vector,
-  KIRQL Irql)
+HalDisableSystemInterrupt(ULONG Vector,
+                          KIRQL Irql)
 {
-  UNIMPLEMENTED;
-
-  return TRUE;
+    UNIMPLEMENTED;
 }
 
 VOID
diff --git a/reactos/hal/halppc/generic/irql.c b/reactos/hal/halppc/generic/irql.c
index bc1604e6c31..2a3b404f596 100644
--- a/reactos/hal/halppc/generic/irql.c
+++ b/reactos/hal/halppc/generic/irql.c
@@ -356,7 +356,7 @@ VOID NTAPI HalEndSystemInterrupt (KIRQL Irql, ULONG Unknown2)
   HalpEndSystemInterrupt(Irql);
 }
 
-BOOLEAN
+VOID
 NTAPI
 HalDisableSystemInterrupt(
   ULONG Vector,
@@ -365,7 +365,10 @@ HalDisableSystemInterrupt(
   ULONG irq;
 
   if (Vector < IRQ_BASE || Vector >= IRQ_BASE + NR_IRQS)
-    return FALSE;
+  {
+    ASSERT(FALSE);
+    return;
+  }
 
   irq = Vector - IRQ_BASE;
   pic_mask.both |= (1 << irq);
@@ -378,7 +381,7 @@ HalDisableSystemInterrupt(
       WRITE_PORT_UCHAR((PUCHAR)0xa1, (UCHAR)(pic_mask.slave|pic_mask_intr.slave));
     }
 
-  return TRUE;
+  return;
 }
 
 
diff --git a/reactos/hal/halx86/mp/mpsirql.c b/reactos/hal/halx86/mp/mpsirql.c
index d8b447583b3..957cffd8f98 100644
--- a/reactos/hal/halx86/mp/mpsirql.c
+++ b/reactos/hal/halx86/mp/mpsirql.c
@@ -336,9 +336,10 @@ HalEndSystemInterrupt (KIRQL Irql,
   HalpLowerIrql (Irql, TRUE);
 }
   
-BOOLEAN NTAPI
-HalDisableSystemInterrupt (ULONG Vector,
-			   KIRQL Irql)
+VOID
+NTAPI
+HalDisableSystemInterrupt(ULONG Vector,
+			              KIRQL Irql)
 {
   ULONG irq;
 
@@ -348,13 +349,14 @@ HalDisableSystemInterrupt (ULONG Vector,
       Vector >= FIRST_DEVICE_VECTOR + NUMBER_DEVICE_VECTORS)  
   {
     DPRINT1("Not a device interrupt, vector=%x\n", Vector);
-    return FALSE;
+    ASSERT(FALSE);
+    return;
   }
 
   irq = VECTOR2IRQ (Vector);
   IOAPICMaskIrq (irq);
 
-  return TRUE;  
+  return;  
 }
 
 
diff --git a/reactos/include/ndk/halfuncs.h b/reactos/include/ndk/halfuncs.h
index 7e318156a29..c4121cc3ddf 100644
--- a/reactos/include/ndk/halfuncs.h
+++ b/reactos/include/ndk/halfuncs.h
@@ -144,7 +144,7 @@ HalClearSoftwareInterrupt(
 );
 
 NTHALAPI
-BOOLEAN
+VOID
 NTAPI
 HalDisableSystemInterrupt(
     ULONG Vector,