diff --git a/engine.pro b/engine.pro
index 51793ea1a51d7d58b01e26cedcb6b13d0232544a..7b65082d7a7150aa21972421d6af4650f09bfad9 100644
--- a/engine.pro
+++ b/engine.pro
@@ -283,7 +283,8 @@ CONFIG(release, debug|release) {
          QMAKE_CXXFLAGS += -Ofast -funroll-loops -fno-signed-zeros -fno-trapping-math
     }
     ios:{
-        QMAKE_CXXFLAGS += -O3
+        CONFIG += ltcg
+        QMAKE_CXXFLAGS += -Ofast -funroll-loops -fno-signed-zeros -fno-trapping-math
     }
 }
 
diff --git a/notifications/ios/applepushnotifications.cpp b/notifications/ios/applepushnotifications.cpp
index 9113a216ec73b702fb631baf04fd3b0b5b607392..4724356af084311421ccb4572bfe351a19db93e1 100755
--- a/notifications/ios/applepushnotifications.cpp
+++ b/notifications/ios/applepushnotifications.cpp
@@ -32,7 +32,7 @@ ApplePushNotifications::ApplePushNotifications()
     connect( mNotificationInstance, &IosNotificationReceiver::switchChannelByName, this, &ApplePushNotifications::onSwitchRequest );
 }
 
-void ApplePushNotifications::receiveMessage( QString pServer, QString pRid, QString pName, QString pType )
+void ApplePushNotifications::receiveMessage( const QString &pServer, const QString &pRid, const QString &pName, const QString &pType )
 {
     emit messageReceived( pServer, pRid, pName, pType );
 }
@@ -60,7 +60,7 @@ void ApplePushNotifications::checkForPendingMessages()
     emit switchChannelByName( mRoomName );
 }
 
-void ApplePushNotifications::onSwitchRequest( QString pName )
+void ApplePushNotifications::onSwitchRequest( const QString &pName )
 {
     mRoomName = pName;
     emit switchChannelByName( pName );
diff --git a/notifications/notificationabstract.h b/notifications/notificationabstract.h
index 2d18b15e6b2aa3ec7747e5a991dea3ee312207ed..b14d3568af478aabd4888e0fd9d97b9b2053669d 100755
--- a/notifications/notificationabstract.h
+++ b/notifications/notificationabstract.h
@@ -46,7 +46,7 @@ class NotificationAbstract : public QObject
     signals:
         void tokenReceived( QString pToken );
         void messageReceived( QString pServer, QString pRid, QString pName, QString pType );
-        void switchChannelByName( QString &pChannel );
+        void switchChannelByName( QString pChannel );
 
 };