Use preincrement for iterators instead of postincrement

src/properties/peerlistwidget.cpp

@@ -312,7 +312,7 @@ void PeerListWidget::loadPeers(const QTorrentHandle &h, bool force_hostname_reso
   h.get_peer_info(peers);
   std::vector<peer_info>::const_iterator itr;
   QSet<QString> old_peers_set = m_peerItems.keys().toSet();
-  for (itr = peers.begin(); itr != peers.end(); itr++) {
+  for (itr = peers.begin(); itr != peers.end(); ++itr) {
     peer_info peer = *itr;
     QString peer_ip = misc::toQString(peer.ip.address().to_string(ec));
     if (ec) continue;

src/properties/trackerlist.cpp

@@ -313,7 +313,7 @@ void TrackerList::deleteSelectedTrackers() {
   std::vector<announce_entry> remaining_trackers;
   std::vector<announce_entry> trackers = h.trackers();
   std::vector<announce_entry>::iterator it;
-  for (it = trackers.begin(); it != trackers.end(); it++) {
+  for (it = trackers.begin(); it != trackers.end(); ++it) {
     if (!urls_to_remove.contains(misc::toQString((*it).url))) {
       remaining_trackers.push_back(*it);
     }

src/properties/trackersadditiondlg.h

@@ -90,7 +90,7 @@ public slots:
     std::vector<libtorrent::announce_entry>::iterator itr = tor_trackers.begin();
     while(itr != tor_trackers.end()) {
       existingTrackers << QUrl(misc::toQString(itr->url));
-      itr++;
+      ++itr;
     }
     // Load from current user list
     QStringList tmp = trackers_list->toPlainText().split("\n");