diff --git a/src/gui/painting/qbackingstore.cpp b/src/gui/painting/qbackingstore.cpp
index 53349dcef4..afd39a6b71 100644
--- a/src/gui/painting/qbackingstore.cpp
+++ b/src/gui/painting/qbackingstore.cpp
@@ -209,6 +209,9 @@ void QBackingStore::beginPaint(const QRegion &region)
 */
 void QBackingStore::endPaint()
 {
+    if (paintDevice()->paintingActive())
+        qWarning() << "QBackingStore::endPaint() called with active painter on backingstore paint device";
+
     d_ptr->platformBackingStore->endPaint();
 }