diff --git a/seafile-client/src/ui/event-details-tree.cpp b/seafile-client/src/ui/event-details-tree.cpp

index 5721c9d..7b9f93a 100644

--- a/seafile-client/src/ui/event-details-tree.cpp

+++ b/seafile-client/src/ui/event-details-tree.cpp

@@ -135,6 +135,7 @@ QString EventDetailsFileItem::etype_desc() const

       case DIR_DELETED:

         return QObject::tr("Deleted");

     };

+    return QString();

 }

 QIcon EventDetailsFileItem::etype_icon() const

@@ -153,6 +154,7 @@ QIcon EventDetailsFileItem::etype_icon() const

       case DIR_DELETED:

         return awesome->icon(icon_minus, QColor("#BD2C00"));

     };

+    return QIcon();

 }

 const char* EventDetailsFileItem::etype_color() const

@@ -171,6 +173,7 @@ const char* EventDetailsFileItem::etype_color() const

       case DIR_DELETED:

         return "#BD2C00";

     };

+    return "";

 }

 bool EventDetailsFileItem::isFileOpenable() const