diff --git a/reactos/ntoskrnl/mm/marea.c b/reactos/ntoskrnl/mm/marea.c
index e39c51a0f7a..be80973a5fb 100644
--- a/reactos/ntoskrnl/mm/marea.c
+++ b/reactos/ntoskrnl/mm/marea.c
@@ -549,7 +549,7 @@ NTSTATUS MmCreateMemoryArea(PEPROCESS Process,
    if (BoundaryAddressMultiple.QuadPart != 0)
      {
       EndAddress = *BaseAddress + tmpLength-1;
-      assert((*BaseAddress/BoundaryAddressMultiple) == (EndAddress/BoundaryAddressMultiple));
+      assert(((DWORD_PTR)*BaseAddress/BoundaryAddressMultiple.QuadPart) == ((DWORD_PTR)EndAddress/BoundaryAddressMultiple.QuadPart));
      }
 
 	if (MmOpenMemoryAreaByRegion(AddressSpace,