diff --git a/reactos/lib/atl/atlcore.h b/reactos/lib/atl/atlcore.h
index 08e19d41382..935b31ed72c 100644
--- a/reactos/lib/atl/atlcore.h
+++ b/reactos/lib/atl/atlcore.h
@@ -101,7 +101,7 @@ class CComAutoCriticalSection : public CComCriticalSection
 public:
 	CComAutoCriticalSection()
 	{
-		HRESULT								hResult;
+		HRESULT hResult __MINGW_ATTRIB_UNUSED;
 
 		hResult = CComCriticalSection::Init();
 		ATLASSERT(SUCCEEDED(hResult));