diff --git a/reactos/lib/rtl/bitmap.c b/reactos/lib/rtl/bitmap.c
index c94c22840a3..5acca0e64c3 100644
--- a/reactos/lib/rtl/bitmap.c
+++ b/reactos/lib/rtl/bitmap.c
@@ -187,8 +187,7 @@ RtlClearBits(PRTL_BITMAP BitMapHeader,
   if (StartingIndex >= Size || NumberToClear == 0)
     return;
 
-  if (StartingIndex + NumberToClear > Size)
-    NumberToClear = Size - StartingIndex;
+  ASSERT(StartingIndex + NumberToClear <= Size);
 
   Ptr = (PULONG)BitMapHeader->Buffer + (StartingIndex / 32);
   while (NumberToClear)