diff --git a/src/corelib/itemmodels/qabstractitemmodel.cpp b/src/corelib/itemmodels/qabstractitemmodel.cpp
index addeeafd45..41bdaa2ac5 100644
--- a/src/corelib/itemmodels/qabstractitemmodel.cpp
+++ b/src/corelib/itemmodels/qabstractitemmodel.cpp
@@ -951,7 +951,9 @@ void QAbstractItemModelPrivate::columnsRemoved(const QModelIndex &parent,
     for (QVector<QPersistentModelIndexData *>::const_iterator it = persistent_invalidated.constBegin();
          it != persistent_invalidated.constEnd(); ++it) {
         QPersistentModelIndexData *data = *it;
-        persistent.indexes.erase(persistent.indexes.constFind(data->index));
+        auto index = persistent.indexes.constFind(data->index);
+        if (index != persistent.indexes.constEnd())
+            persistent.indexes.erase(index);
         data->index = QModelIndex();
     }
 }
diff --git a/src/gui/itemmodels/qstandarditemmodel.cpp b/src/gui/itemmodels/qstandarditemmodel.cpp
index fc9424763e..d0325a7f9e 100644
--- a/src/gui/itemmodels/qstandarditemmodel.cpp
+++ b/src/gui/itemmodels/qstandarditemmodel.cpp
@@ -3150,7 +3150,7 @@ QMimeData *QStandardItemModel::mimeData(const QModelIndexList &indexes) const
             for (int i = 0; i < childList.count(); ++i) {
                 QStandardItem *chi = childList.at(i);
                 if (chi) {
-                    itemsSet.erase(itemsSet.constFind(chi));
+                    itemsSet.remove(chi);
                     stack.push(chi);
                 }
             }