2 files changed, 17 insertions, 10 deletions

diff --git a/src/gui/util/qundostack.cpp b/src/gui/util/qundostack.cpp
index 3d1d8a2b788..27b131cd733 100644
--- a/src/gui/util/qundostack.cpp
+++ b/src/gui/util/qundostack.cpp
@@ -425,16 +425,16 @@ void QUndoStackPrivate::setIndex(int idx, bool clean)
         emit q->indexChanged(index);
     }
 
-    const ActionState newUndoState{q->canUndo(), q->undoText()};
-    if (indexChanged || newUndoState != undoActionState) {
-        undoActionState = newUndoState;
+    if (ActionState newUndoState{q->canUndo(), q->undoText()};
+        indexChanged || newUndoState != undoActionState) {
+        undoActionState = std::move(newUndoState);
         emit q->canUndoChanged(undoActionState.enabled);
         emit q->undoTextChanged(undoActionState.text);
     }
 
-    const ActionState newRedoState{q->canRedo(), q->redoText()};
-    if (indexChanged || newRedoState != redoActionState) {
-        redoActionState = newRedoState;
+    if (ActionState newRedoState{q->canRedo(), q->redoText()};
+        indexChanged || newRedoState != redoActionState) {
+        redoActionState = std::move(newRedoState);
         emit q->canRedoChanged(redoActionState.enabled);
         emit q->redoTextChanged(redoActionState.text);
     }
diff --git a/src/gui/util/qundostack_p.h b/src/gui/util/qundostack_p.h
index fea201ce62d..6bdcf5fb20b 100644
--- a/src/gui/util/qundostack_p.h
+++ b/src/gui/util/qundostack_p.h
@@ -59,10 +59,17 @@ public:
         bool enabled = false;
         QString text;
 
-        bool operator!=(const ActionState &other) const noexcept
-        {
-            return enabled != other.enabled || text != other.text;
-        }
+        friend bool operator==(const ActionState &lhs, const ActionState &rhs) noexcept
+#ifdef __cpp_impl_three_way_comparison
+            = default;
+#else
+        { return lhs.enabled == rhs.enabled && lhs.text == rhs.text; }
+        friend bool operator!=(const ActionState &lhs, const ActionState &rhs) noexcept
+        { return !(lhs == rhs); }
+#endif
+        // some compiler's reject seed = 0) = delete, overload instead:
+        friend void qHash(const ActionState &key, size_t seed) = delete;
+        friend void qHash(const ActionState &key) = delete;
     };
 
     QList<QUndoCommand*> command_list;