diff --git a/Editor/LayersEditor.cpp b/Editor/LayersEditor.cpp
index 5209e64..4a41f24 100644
--- a/Editor/LayersEditor.cpp
+++ b/Editor/LayersEditor.cpp
@@ -519,7 +519,7 @@ void LayersTableView::deleteSelection() {
 
   std::vector<std::pair<amuse::LayerMapping, int>> data;
   data.reserve(list.size());
-  for (const QModelIndex idx : list) {
+  for (const QModelIndex& idx : list) {
     data.emplace_back(amuse::LayerMapping{}, idx.row());
   }
 
diff --git a/Editor/SongGroupEditor.cpp b/Editor/SongGroupEditor.cpp
index e53318a..9111ed7 100644
--- a/Editor/SongGroupEditor.cpp
+++ b/Editor/SongGroupEditor.cpp
@@ -1172,7 +1172,7 @@ void PageTableView::deleteSelection() {
 
   std::vector<std::pair<uint8_t, amuse::SongGroupIndex::PageEntry>> data;
   data.reserve(list.size());
-  for (const QModelIndex idx : list) {
+  for (const QModelIndex& idx : list) {
     data.emplace_back(model()->data(idx).toInt() - 1, amuse::SongGroupIndex::PageEntry{});
   }
 
diff --git a/Editor/SoundMacroEditor.cpp b/Editor/SoundMacroEditor.cpp
index ece3865..64ab342 100644
--- a/Editor/SoundMacroEditor.cpp
+++ b/Editor/SoundMacroEditor.cpp
@@ -243,7 +243,7 @@ CommandWidget::CommandWidget(QWidget* parent, amuse::SoundMacro::ICmd* cmd, amus
           cb->setFixedHeight(30);
           cb->setProperty("fieldIndex", f);
           cb->setProperty("fieldName", fieldName);
-          for (const auto choice : field.m_choices) {
+          for (const auto& choice : field.m_choices) {
             if (choice.empty()) {
               break;
             }