diff --git a/sdk/lib/atl/atlwin.h b/sdk/lib/atl/atlwin.h
index 71d28fe2989..c25fd1404d0 100644
--- a/sdk/lib/atl/atlwin.h
+++ b/sdk/lib/atl/atlwin.h
@@ -1579,8 +1579,8 @@ public:
         LONG_PTR saveWindowProc;
 
         ATLASSERT(pThis != NULL);
-        ATLASSERT((pThis->m_dwState & WINSTATE_DESTROYED) == 0);
-        ATLASSERT(pThis->m_hWnd != NULL);
+        ATLASSERT(pThis != NULL && (pThis->m_dwState & WINSTATE_DESTROYED) == 0);
+        ATLASSERT(pThis != NULL && pThis->m_hWnd != NULL);
         if (pThis == NULL || (pThis->m_dwState & WINSTATE_DESTROYED) != 0 || pThis->m_hWnd == NULL)
             return 0;