6 files changed, 33 insertions, 4 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoamenu.h b/src/plugins/platforms/cocoa/qcocoamenu.h
index 06688dbf3d..7baaf971f4 100644
--- a/src/plugins/platforms/cocoa/qcocoamenu.h
+++ b/src/plugins/platforms/cocoa/qcocoamenu.h
@@ -98,6 +98,8 @@ public:
 
     void timerEvent(QTimerEvent *e) Q_DECL_OVERRIDE;
 
+    void syncMenuItem_helper(QPlatformMenuItem *menuItem, bool menubarUpdate);
+
 private:
     QCocoaMenuItem *itemOrNull(int index) const;
     void insertNative(QCocoaMenuItem *item, QCocoaMenuItem *beforeItem);
diff --git a/src/plugins/platforms/cocoa/qcocoamenu.mm b/src/plugins/platforms/cocoa/qcocoamenu.mm
index 3a11023a4d..8bdd0512de 100644
--- a/src/plugins/platforms/cocoa/qcocoamenu.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenu.mm
@@ -435,6 +435,11 @@ void QCocoaMenu::timerEvent(QTimerEvent *e)
 
 void QCocoaMenu::syncMenuItem(QPlatformMenuItem *menuItem)
 {
+    syncMenuItem_helper(menuItem, false /*menubarUpdate*/);
+}
+
+void QCocoaMenu::syncMenuItem_helper(QPlatformMenuItem *menuItem, bool menubarUpdate)
+{
     QMacAutoReleasePool pool;
     QCocoaMenuItem *cocoaItem = static_cast<QCocoaMenuItem *>(menuItem);
     if (!m_menuItems.contains(cocoaItem)) {
@@ -444,8 +449,9 @@ void QCocoaMenu::syncMenuItem(QPlatformMenuItem *menuItem)
 
     const bool wasMerged = cocoaItem->isMerged();
     NSMenuItem *oldItem = cocoaItem->nsItem();
+    NSMenuItem *syncedItem = cocoaItem->sync();
 
-    if (cocoaItem->sync() != oldItem) {
+    if (syncedItem != oldItem) {
         // native item was changed for some reason
         if (oldItem) {
             if (wasMerged) {
@@ -463,6 +469,14 @@ void QCocoaMenu::syncMenuItem(QPlatformMenuItem *menuItem)
         // when an item's enabled state changes after menuWillOpen:
         scheduleUpdate();
     }
+
+    // This may be a good moment to attach this item's eventual submenu to the
+    // synced item, but only on the condition we're all currently hooked to the
+    // menunbar. A good indicator of this being the right moment is knowing that
+    // we got called from QCocoaMenuBar::updateMenuBarImmediately().
+    if (menubarUpdate)
+        if (QCocoaMenu *submenu = cocoaItem->menu())
+            submenu->setAttachedItem(syncedItem);
 }
 
 void QCocoaMenu::syncSeparatorsCollapsible(bool enable)
diff --git a/src/plugins/platforms/cocoa/qcocoamenubar.h b/src/plugins/platforms/cocoa/qcocoamenubar.h
index 0725e9db68..a4ee531e91 100644
--- a/src/plugins/platforms/cocoa/qcocoamenubar.h
+++ b/src/plugins/platforms/cocoa/qcocoamenubar.h
@@ -72,6 +72,8 @@ public:
     QList<QCocoaMenuItem*> merged() const;
     NSMenuItem *itemForRole(QPlatformMenuItem::MenuRole r);
 
+    void syncMenu_helper(QPlatformMenu *menu, bool menubarUpdate);
+
 private:
     static QCocoaWindow *findWindowForMenubar();
     static QCocoaMenuBar *findGlobalMenubar();
diff --git a/src/plugins/platforms/cocoa/qcocoamenubar.mm b/src/plugins/platforms/cocoa/qcocoamenubar.mm
index 3e466c9587..a4cd465dae 100644
--- a/src/plugins/platforms/cocoa/qcocoamenubar.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenubar.mm
@@ -155,7 +155,7 @@ void QCocoaMenuBar::insertMenu(QPlatformMenu *platformMenu, QPlatformMenu *befor
         }
     }
 
-    syncMenu(menu);
+    syncMenu_helper(menu, false /*internaCall*/);
 
     if (needsImmediateUpdate())
         updateMenuBarImmediately();
@@ -183,11 +183,16 @@ void QCocoaMenuBar::removeMenu(QPlatformMenu *platformMenu)
 
 void QCocoaMenuBar::syncMenu(QPlatformMenu *menu)
 {
+    syncMenu_helper(menu, false /*internaCall*/);
+}
+
+void QCocoaMenuBar::syncMenu_helper(QPlatformMenu *menu, bool menubarUpdate)
+{
     QMacAutoReleasePool pool;
 
     QCocoaMenu *cocoaMenu = static_cast<QCocoaMenu *>(menu);
     Q_FOREACH (QCocoaMenuItem *item, cocoaMenu->items())
-        cocoaMenu->syncMenuItem(item);
+        cocoaMenu->syncMenuItem_helper(item, menubarUpdate);
 
     BOOL shouldHide = YES;
     if (cocoaMenu->isVisible()) {
@@ -357,7 +362,7 @@ void QCocoaMenuBar::updateMenuBarImmediately()
         menu->setAttachedItem(item);
         menu->setMenuParent(mb);
         // force a sync?
-        mb->syncMenu(menu);
+        mb->syncMenu_helper(menu, true /*menubarUpdate*/);
         menu->propagateEnabledState(!disableForModal);
     }
 
diff --git a/tests/manual/cocoa/menurama/mainwindow.cpp b/tests/manual/cocoa/menurama/mainwindow.cpp
index 06867bd7c9..086fc1e2fa 100644
--- a/tests/manual/cocoa/menurama/mainwindow.cpp
+++ b/tests/manual/cocoa/menurama/mainwindow.cpp
@@ -37,6 +37,11 @@ MainWindow::MainWindow(QWidget *parent) :
 {
     ui->setupUi(this);
 
+    auto *a = ui->menuStuff->addAction("Enabled Submenu (QTBUG-63172)");
+    auto *qtbug63172_Menu = new QMenu;
+    qtbug63172_Menu->addAction("We're Good!");
+    a->setMenu(qtbug63172_Menu);
+
     startTimer(1000);
 
     connect(ui->menuAfter_aboutToShow, &QMenu::aboutToShow, [=] {
diff --git a/tests/manual/cocoa/menurama/mainwindow.ui b/tests/manual/cocoa/menurama/mainwindow.ui
index 18cded70d2..4fb3e3420e 100644
--- a/tests/manual/cocoa/menurama/mainwindow.ui
+++ b/tests/manual/cocoa/menurama/mainwindow.ui
@@ -131,6 +131,7 @@ Click on &quot;Dynamic Stuff&quot; then move left and right to other menus. Disa
     <addaction name="menuSubmenu"/>
     <addaction name="actionDisabled_Item"/>
     <addaction name="menuDisabled_Submenu"/>
+    <addaction name="separator"/>
    </widget>
    <widget class="QMenu" name="menuDisabled_Stuff">
     <property name="enabled">