Appended references to const auto types in loop to prevent copying.

Suggested by Apple Clang.

Telegram/SourceFiles/api/api_user_privacy.cpp

@@ -28,7 +28,7 @@ TLInputRules RulesToTL(const UserPrivacy::Rule &rule) {
 	const auto collectInputUsers = [](const auto &peers) {
 		auto result = QVector<MTPInputUser>();
 		result.reserve(peers.size());
-		for (const auto peer : peers) {
+		for (const auto &peer : peers) {
 			if (const auto user = peer->asUser()) {
 				result.push_back(user->inputUser);
 			}
@@ -38,7 +38,7 @@ TLInputRules RulesToTL(const UserPrivacy::Rule &rule) {
 	const auto collectInputChats = [](const auto &peers) {
 		auto result = QVector<MTPlong>();
 		result.reserve(peers.size());
-		for (const auto peer : peers) {
+		for (const auto &peer : peers) {
 			if (!peer->isUser()) {
 				result.push_back(peerToBareMTPInt(peer->id));
 			}
@@ -112,7 +112,7 @@ UserPrivacy::Rule TLToRules(const TLRules &rules, Data::Session &owner) {
 		}, [&](const MTPDprivacyValueAllowUsers &data) {
 			const auto &users = data.vusers().v;
 			always.reserve(always.size() + users.size());
-			for (const auto userId : users) {
+			for (const auto &userId : users) {
 				const auto user = owner.user(UserId(userId.v));
 				if (!base::contains(never, user)
 					&& !base::contains(always, user)) {
@@ -140,7 +140,7 @@ UserPrivacy::Rule TLToRules(const TLRules &rules, Data::Session &owner) {
 		}, [&](const MTPDprivacyValueDisallowUsers &data) {
 			const auto &users = data.vusers().v;
 			never.reserve(never.size() + users.size());
-			for (const auto userId : users) {
+			for (const auto &userId : users) {
 				const auto user = owner.user(UserId(userId.v));
 				if (!base::contains(always, user)
 					&& !base::contains(never, user)) {

Telegram/SourceFiles/apiwrap.cpp

@@ -1295,7 +1295,7 @@ void ApiWrap::markMediaRead(
 		not_null<ChannelData*>,
 		QVector<MTPint>>();
 	markedIds.reserve(items.size());
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if ((!item->isUnreadMedia() || item->out())
 			&& !item->isUnreadMention()) {
 			continue;
@@ -2400,7 +2400,7 @@ void ApiWrap::applyAffectedMessages(
 void ApiWrap::saveCurrentDraftToCloud() {
 	Core::App().saveCurrentDraftsToHistories();
 
-	for (const auto controller : _session->windows()) {
+	for (const auto &controller : _session->windows()) {
 		if (const auto history = controller->activeChatCurrent().history()) {
 			_session->local().writeDrafts(history);
 
@@ -3415,7 +3415,7 @@ void ApiWrap::addChatParticipants(
 		const std::vector<not_null<UserData*>> &users,
 		Fn<void(bool)> done) {
 	if (const auto chat = peer->asChat()) {
-		for (const auto user : users) {
+		for (const auto &user : users) {
 			request(MTPmessages_AddChatUser(
 				chat->inputChat,
 				user->inputUser,
@@ -3450,7 +3450,7 @@ void ApiWrap::addChatParticipants(
 				if (callback) callback(false);
 			}).afterDelay(crl::time(5)).send();
 		};
-		for (const auto user : users) {
+		for (const auto &user : users) {
 			list.push_back(user->inputUser);
 			if (list.size() == kMaxUsersPerInvite) {
 				send();

Telegram/SourceFiles/boxes/confirm_box.cpp

@@ -719,7 +719,7 @@ void DeleteMessagesBox::prepare() {
 }
 
 bool DeleteMessagesBox::hasScheduledMessages() const {
-	for (const auto fullId : std::as_const(_ids)) {
+	for (const auto &fullId : _ids) {
 		if (const auto item = _session->data().message(fullId)) {
 			if (item->isScheduled()) {
 				return true;
@@ -731,7 +731,7 @@ bool DeleteMessagesBox::hasScheduledMessages() const {
 
 PeerData *DeleteMessagesBox::checkFromSinglePeer() const {
 	auto result = (PeerData*)nullptr;
-	for (const auto fullId : std::as_const(_ids)) {
+	for (const auto &fullId : _ids) {
 		if (const auto item = _session->data().message(fullId)) {
 			const auto peer = item->history()->peer;
 			if (!result) {
@@ -881,7 +881,7 @@ void DeleteMessagesBox::deleteAndClear() {
 		if (justClear) {
 			peer->session().api().clearHistory(peer, revoke);
 		} else {
-			for (const auto controller : peer->session().windows()) {
+			for (const auto &controller : peer->session().windows()) {
 				if (controller->activeChatCurrent().peer() == peer) {
 					Ui::showChatsList(&peer->session());
 				}

Telegram/SourceFiles/boxes/confirm_phone_box.cpp

@@ -106,7 +106,7 @@ void SentCodeField::fix() {
 	auto newPos = -1;
 	auto oldLen = now.size();
 	auto digitCount = 0;
-	for (const auto ch : now) {
+	for (const auto &ch : now) {
 		if (ch.isDigit()) {
 			++digitCount;
 		}
@@ -120,7 +120,7 @@ void SentCodeField::fix() {
 
 	newText.reserve(oldLen);
 	int i = 0;
-	for (const auto ch : now) {
+	for (const auto &ch : now) {
 		if (i++ == oldPos) {
 			newPos = newText.length();
 		}

Telegram/SourceFiles/boxes/filters/edit_filter_box.cpp

@@ -186,7 +186,7 @@ void FilterChatsPreview::updateData(
 				makeButton([=] { removeFlag(flag); }) });
 		}
 	}
-	for (const auto history : peers) {
+	for (const auto &history : peers) {
 		_removePeer.push_back(PeerButton{
 			.history = history,
 			.button = makeButton([=] { removePeer(history); })

Telegram/SourceFiles/boxes/filters/edit_filter_chats_list.cpp

@@ -342,7 +342,7 @@ void EditFilterChatsListController::prepareViewHook() {
 	const auto count = int(_peers.size());
 	const auto rows = std::make_unique<std::optional<ExceptionRow>[]>(count);
 	auto i = 0;
-	for (const auto history : _peers) {
+	for (const auto &history : _peers) {
 		rows[i++].emplace(history);
 	}
 	auto pointers = std::vector<ExceptionRow*>();

Telegram/SourceFiles/boxes/peer_list_box.cpp

@@ -186,7 +186,7 @@ void PeerListBox::paintEvent(QPaintEvent *e) {
 	const auto &bg = (_controller->listSt()
 		? *_controller->listSt()
 		: st::peerListBox).bg;
-	for (const auto rect : e->region()) {
+	for (const auto &rect : e->region()) {
 		p.fillRect(rect, bg);
 	}
 }
@@ -1693,7 +1693,7 @@ void PeerListContent::searchQueryChanged(QString query) {
 				};
 
 				_filterResults.reserve(minimalList->size());
-				for (const auto row : *minimalList) {
+				for (const auto &row : *minimalList) {
 					if (!row->special() && allSearchWordsInNames(row->peer())) {
 						_filterResults.push_back(row);
 					}
@@ -1999,4 +1999,4 @@ void PeerListContentDelegate::peerListShowRowMenu(
 		bool highlightRow,
 		Fn<void(not_null<Ui::PopupMenu *>)> destroyed) {
 	_content->showRowMenu(row, highlightRow, std::move(destroyed));
-}
+}

Telegram/SourceFiles/boxes/peer_list_controllers.cpp

@@ -288,7 +288,7 @@ void ChatsListBoxController::rebuildRows() {
 	auto wasEmpty = !delegate()->peerListFullRowsCount();
 	auto appendList = [this](auto chats) {
 		auto count = 0;
-		for (const auto row : chats->all()) {
+		for (const auto &row : chats->all()) {
 			if (const auto history = row->history()) {
 				if (appendRow(history)) {
 					++count;
@@ -389,7 +389,7 @@ void ContactsBoxController::prepare() {
 void ContactsBoxController::rebuildRows() {
 	const auto appendList = [&](auto chats) {
 		auto count = 0;
-		for (const auto row : chats->all()) {
+		for (const auto &row : chats->all()) {
 			if (const auto history = row->history()) {
 				if (const auto user = history->peer->asUser()) {
 					if (appendRow(user)) {

Telegram/SourceFiles/boxes/peer_lists_box.cpp

@@ -283,7 +283,7 @@ void PeerListsBox::paintEvent(QPaintEvent *e) {
 	const auto &bg = (firstController()->listSt()
 		? *firstController()->listSt()
 		: st::peerListBox).bg;
-	for (const auto rect : e->region()) {
+	for (const auto &rect : e->region()) {
 		p.fillRect(rect, bg);
 	}
 }

Telegram/SourceFiles/boxes/peers/add_participants_box.cpp

@@ -429,7 +429,7 @@ void AddSpecialBoxController::rebuildChatRows(not_null<ChatData*> chat) {
 			--count;
 		}
 	}
-	for (const auto user : participants) {
+	for (const auto &user : participants) {
 		if (auto row = createRow(user)) {
 			delegate()->peerListAppendRow(std::move(row));
 		}
@@ -1155,7 +1155,7 @@ void AddSpecialBoxSearchController::addChatMembers(
 		return true;
 	};
 
-	for (const auto user : chat->participants) {
+	for (const auto &user : chat->participants) {
 		if (allWordsAreFound(user->nameWords())) {
 			delegate()->peerListSearchAddRow(user);
 		}
@@ -1210,7 +1210,7 @@ void AddSpecialBoxSearchController::addChatsContacts() {
 		if (!index) {
 			return;
 		}
-		for (const auto row : *index) {
+		for (const auto &row : *index) {
 			if (const auto history = row->history()) {
 				if (const auto user = history->peer->asUser()) {
 					if (allWordsAreFound(user->nameWords())) {

Telegram/SourceFiles/boxes/peers/edit_participants_box.cpp

@@ -702,7 +702,7 @@ void ParticipantsAdditionalData::migrate(
 	_peer = channel;
 	fillFromChannel(channel);
 
-	for (const auto user : _admins) {
+	for (const auto &user : _admins) {
 		_adminRights.emplace(user, chat->defaultAdminRights(user));
 		if (channel->amCreator()) {
 			_adminCanEdit.emplace(user);
@@ -1197,7 +1197,7 @@ void ParticipantsBoxController::rebuildChatParticipants(
 			--count;
 		}
 	}
-	for (const auto user : participants) {
+	for (const auto &user : participants) {
 		if (auto row = createRow(user)) {
 			delegate()->peerListAppendRow(std::move(row));
 		}

Telegram/SourceFiles/boxes/share_box.cpp

@@ -560,7 +560,7 @@ ShareBox::Inner::Inner(QWidget *parent, const Descriptor &descriptor)
 		_chatsIndexed->addToEnd(self->owner().history(self));
 	}
 	const auto addList = [&](not_null<Dialogs::IndexedList*> list) {
-		for (const auto row : list->all()) {
+		for (const auto &row : list->all()) {
 			if (const auto history = row->history()) {
 				if (!history->peer->isSelf()
 					&& _descriptor.filterCallback(history->peer)) {
@@ -703,7 +703,7 @@ void ShareBox::Inner::repaintChat(not_null<PeerData*> peer) {
 int ShareBox::Inner::chatIndex(not_null<PeerData*> peer) const {
 	int index = 0;
 	if (_filter.isEmpty()) {
-		for (const auto row : _chatsIndexed->all()) {
+		for (const auto &row : _chatsIndexed->all()) {
 			if (const auto history = row->history()) {
 				if (history->peer == peer) {
 					return index;
@@ -712,7 +712,7 @@ int ShareBox::Inner::chatIndex(not_null<PeerData*> peer) const {
 			++index;
 		}
 	} else {
-		for (const auto row : _filtered) {
+		for (const auto &row : _filtered) {
 			if (const auto history = row->history()) {
 				if (history->peer == peer) {
 					return index;

Telegram/SourceFiles/calls/calls_panel.cpp

@@ -773,7 +773,7 @@ void Panel::paint(QRect clip) {
 	if (!_incoming->widget()->isHidden()) {
 		region = region.subtracted(QRegion(_incoming->widget()->geometry()));
 	}
-	for (const auto rect : region) {
+	for (const auto &rect : region) {
 		p.fillRect(rect, st::callBgOpaque);
 	}
 	if (_incoming && _incoming->widget()->isHidden()) {

Telegram/SourceFiles/calls/group/calls_group_call.cpp

@@ -3157,7 +3157,7 @@ std::variant<int, not_null<UserData*>> GroupCall::inviteUsers(
 		}).send();
 		slice.clear();
 	};
-	for (const auto user : users) {
+	for (const auto &user : users) {
 		if (!count && slice.empty()) {
 			result = user;
 		}

Telegram/SourceFiles/calls/group/calls_group_members.cpp

@@ -481,7 +481,7 @@ void Members::Controller::toggleVideoEndpointActive(
 
 void Members::Controller::appendInvitedUsers() {
 	if (const auto id = _call->id()) {
-		for (const auto user : _peer->owner().invitedToCallUsers(id)) {
+		for (const auto &user : _peer->owner().invitedToCallUsers(id)) {
 			if (auto row = createInvitedRow(user)) {
 				delegate()->peerListAppendRow(std::move(row));
 			}
@@ -1149,7 +1149,7 @@ void Members::Controller::showRowMenu(
 			return;
 		}
 		auto saved = base::take(_menu);
-		for (const auto peer : base::take(_menuCheckRowsAfterHidden)) {
+		for (const auto &peer : base::take(_menuCheckRowsAfterHidden)) {
 			if (const auto row = findRow(peer)) {
 				checkRowPosition(row);
 			}

Telegram/SourceFiles/calls/group/calls_group_panel.cpp

@@ -2179,7 +2179,7 @@ void Panel::paint(QRect clip) {
 	Painter p(widget());
 
 	auto region = QRegion(clip);
-	for (const auto rect : region) {
+	for (const auto &rect : region) {
 		p.fillRect(rect, st::groupCallBg);
 	}
 }

Telegram/SourceFiles/calls/group/calls_group_viewport_raster.cpp

@@ -50,7 +50,7 @@ void Viewport::RendererSW::paintFallback(
 		}
 		paintTile(p, tile.get(), bounding, bg);
 	}
-	for (const auto rect : bg) {
+	for (const auto &rect : bg) {
 		p.fillRect(rect, st::groupCallBg);
 	}
 	for (auto i = _tileData.begin(); i != _tileData.end();) {

Telegram/SourceFiles/chat_helpers/emoji_sets_manager.cpp

@@ -247,7 +247,7 @@ void Row::paintPreview(Painter &p) const {
 	const auto width = st::manageEmojiPreviewWidth;
 	const auto height = st::manageEmojiPreviewWidth;
 	auto &&preview = ranges::views::zip(_preview, ranges::views::ints(0, int(_preview.size())));
-	for (const auto &[pixmap, index] : preview) {
+	for (const auto [pixmap, index] : preview) {
 		const auto row = (index / 2);
 		const auto column = (index % 2);
 		const auto left = x + (column ? width - st::manageEmojiPreview : 0);

Telegram/SourceFiles/chat_helpers/field_autocomplete.cpp

@@ -411,7 +411,7 @@ void FieldAutocomplete::updateFiltered(bool resetScroll) {
 			if (_chat->noParticipantInfo()) {
 				_chat->session().api().requestFullPeer(_chat);
 			} else if (!_chat->participants.empty()) {
-				for (const auto user : _chat->participants) {
+				for (const auto &user : _chat->participants) {
 					if (user->isInaccessible()) continue;
 					if (!listAllSuggestions && filterNotPassedByName(user)) continue;
 					if (indexOfInFirstN(mrows, user, recentInlineBots) >= 0) continue;
@@ -469,7 +469,7 @@ void FieldAutocomplete::updateFiltered(bool resetScroll) {
 				_chat->session().api().requestFullPeer(_chat);
 			} else if (!_chat->participants.empty()) {
 				const auto &commands = _chat->botCommands();
-				for (const auto user : _chat->participants) {
+				for (const auto &user : _chat->participants) {
 					if (!user->isBot()) {
 						continue;
 					}
@@ -493,7 +493,7 @@ void FieldAutocomplete::updateFiltered(bool resetScroll) {
 				}
 			} else {
 				const auto &commands = _channel->mgInfo->botCommands();
-				for (const auto user : _channel->mgInfo->bots) {
+				for (const auto &user : _channel->mgInfo->bots) {
 					if (!user->isBot()) {
 						continue;
 					}

Telegram/SourceFiles/chat_helpers/message_field.cpp

@@ -331,7 +331,7 @@ void InitSpellchecker(
 
 bool HasSendText(not_null<const Ui::InputField*> field) {
 	const auto &text = field->getTextWithTags().text;
-	for (const auto ch : text) {
+	for (const auto &ch : text) {
 		const auto code = ch.unicode();
 		if (code != ' '
 			&& code != '\n'

Telegram/SourceFiles/chat_helpers/stickers_dice_pack.cpp

@@ -86,7 +86,7 @@ void DicePack::applySet(const MTPDmessages_stickerSet &data) {
 			if (index < 0 || index > 6) {
 				return;
 			}
-			for (const auto id : data.vdocuments().v) {
+			for (const auto &id : data.vdocuments().v) {
 				if (const auto document = documents.take(id.v)) {
 					_map.emplace(index, *document);
 				}

Telegram/SourceFiles/core/application.cpp

@@ -1032,7 +1032,7 @@ void Application::registerLeaveSubscription(not_null<QWidget*> widget) {
 			const auto check = [=](not_null<QEvent*> e) {
 				if (e->type() == QEvent::Leave) {
 					if (const auto taken = _leaveFilters.take(window)) {
-						for (const auto weak : taken->registered) {
+						for (const auto &weak : taken->registered) {
 							if (const auto widget = weak.data()) {
 								QEvent ev(QEvent::Leave);
 								QCoreApplication::sendEvent(widget, &ev);

Telegram/SourceFiles/core/changelogs.cpp

@@ -192,7 +192,7 @@ void Changelogs::addLocalLog(const QString &text) {
 };
 
 void Changelogs::addBetaLogs() {
-	for (const auto [version, changes] : BetaLogs()) {
+	for (const auto &[version, changes] : BetaLogs()) {
 		addBetaLog(version, changes);
 	}
 }

Telegram/SourceFiles/core/core_settings.cpp

@@ -82,7 +82,7 @@ QByteArray Settings::serialize() const {
 	auto recentEmojiPreloadGenerated = std::vector<RecentEmojiId>();
 	if (_recentEmojiPreload.empty()) {
 		recentEmojiPreloadGenerated.reserve(_recentEmoji.size());
-		for (const auto [emoji, rating] : _recentEmoji) {
+		for (const auto &[emoji, rating] : _recentEmoji) {
 			recentEmojiPreloadGenerated.push_back({ emoji->id(), rating });
 		}
 	}
@@ -713,7 +713,7 @@ EmojiPack Settings::recentEmojiSection() const {
 
 	auto result = EmojiPack();
 	result.reserve(recent.size());
-	for (const auto [emoji, rating] : recent) {
+	for (const auto &[emoji, rating] : recent) {
 		result.push_back(emoji);
 	}
 	return result;

Telegram/SourceFiles/data/data_changes.cpp

@@ -78,7 +78,7 @@ rpl::producer<UpdateType> Changes::Manager<DataType, UpdateType>::flagsValue(
 
 template <typename DataType, typename UpdateType>
 void Changes::Manager<DataType, UpdateType>::sendNotifications() {
-	for (const auto [data, flags] : base::take(_updates)) {
+	for (const auto &[data, flags] : base::take(_updates)) {
 		_stream.fire({ data, flags });
 	}
 }

Telegram/SourceFiles/data/data_channel.cpp

@@ -664,7 +664,7 @@ QString ChannelData::invitePeekHash() const {
 void ChannelData::privateErrorReceived() {
 	if (const auto expires = invitePeekExpires()) {
 		const auto hash = invitePeekHash();
-		for (const auto window : session().windows()) {
+		for (const auto &window : session().windows()) {
 			clearInvitePeek();
 			Api::CheckChatInvite(window, hash, this);
 			return;

Telegram/SourceFiles/data/data_chat_filters.cpp

@@ -122,18 +122,18 @@ MTPDialogFilter ChatFilter::tl(FilterId replaceId) const {
 	auto always = _always;
 	auto pinned = QVector<MTPInputPeer>();
 	pinned.reserve(_pinned.size());
-	for (const auto history : _pinned) {
+	for (const auto &history : _pinned) {
 		pinned.push_back(history->peer->input);
 		always.remove(history);
 	}
 	auto include = QVector<MTPInputPeer>();
 	include.reserve(always.size());
-	for (const auto history : always) {
+	for (const auto &history : always) {
 		include.push_back(history->peer->input);
 	}
 	auto never = QVector<MTPInputPeer>();
 	never.reserve(_never.size());
-	for (const auto history : _never) {
+	for (const auto &history : _never) {
 		never.push_back(history->peer->input);
 	}
 	return MTP_dialogFilter(
@@ -417,7 +417,7 @@ bool ChatFilters::applyOrder(const QVector<MTPint> &order) {
 		&ChatFilter::id
 	) | ranges::to_vector;
 	auto b = indices.begin(), e = indices.end();
-	for (const auto id : order) {
+	for (const auto &id : order) {
 		const auto i = ranges::find(b, e, id.v);
 		if (i == e) {
 			return false;
@@ -428,7 +428,7 @@ bool ChatFilters::applyOrder(const QVector<MTPint> &order) {
 	}
 	auto changed = false;
 	auto begin = _list.begin(), end = _list.end();
-	for (const auto id : order) {
+	for (const auto &id : order) {
 		const auto i = ranges::find(begin, end, id.v, &ChatFilter::id);
 		Assert(i != end);
 		if (i != begin) {
@@ -526,7 +526,7 @@ bool ChatFilters::loadNextExceptions(bool chatsListLoaded) {
 		const auto i = ranges::find(_list, id, &ChatFilter::id);
 		if (i != end(_list)) {
 			result.reserve(i->always().size());
-			for (const auto history : i->always()) {
+			for (const auto &history : i->always()) {
 				if (!history->folderKnown()) {
 					inputs.push_back(
 						MTP_inputDialogPeer(history->peer->input));

Telegram/SourceFiles/data/data_cloud_themes.cpp

@@ -49,7 +49,7 @@ CloudTheme CloudTheme::Parse(
 		if (const auto settings = data.vsettings()) {
 			settings->match([&](const MTPDthemeSettings &data) {
 				if (const auto colors = data.vmessage_colors()) {
-					for (const auto color : colors->v) {
+					for (const auto &color : colors->v) {
 						result.push_back(ColorFromSerialized(color));
 					}
 				}

Telegram/SourceFiles/data/data_document.cpp

@@ -388,7 +388,7 @@ void DocumentData::setattributes(
 				0x2066, // LTR Isolate
 				0x2067, // RTL Isolate
 			};
-			for (const auto ch : controls) {
+			for (const auto &ch : controls) {
 				_filename = std::move(_filename).replace(ch, "_");
 			}
 		}, [&](const MTPDdocumentAttributeHasStickers &data) {

Telegram/SourceFiles/data/data_drafts.h

@@ -126,7 +126,7 @@ private:
 using HistoryDrafts = base::flat_map<DraftKey, std::unique_ptr<Draft>>;
 
 inline bool draftStringIsEmpty(const QString &text) {
-	for (const auto ch : text) {
+	for (const auto &ch : text) {
 		if (!ch.isSpace()) {
 			return false;
 		}

Telegram/SourceFiles/data/data_groups.cpp

@@ -140,7 +140,7 @@ const Group *Groups::find(not_null<const HistoryItem*> item) const {
 }
 
 void Groups::refreshViews(const HistoryItemsList &items) {
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		_data->requestItemViewRefresh(item);
 	}
 }

Telegram/SourceFiles/data/data_histories.cpp

@@ -333,7 +333,7 @@ void Histories::sendDialogRequests() {
 	}
 
 	const auto finalize = [=] {
-		for (const auto history : histories) {
+		for (const auto &history : histories) {
 			const auto state = lookup(history);
 			if (!state || !state->postponedRequestEntry) {
 				dialogEntryApplied(history);
@@ -667,7 +667,7 @@ void Histories::deleteMessages(const MessageIdsList &ids, bool revoke) {
 	remove.reserve(ids.size());
 	base::flat_map<not_null<History*>, QVector<MTPint>> idsByPeer;
 	base::flat_map<not_null<PeerData*>, QVector<MTPint>> scheduledIdsByPeer;
-	for (const auto itemId : ids) {
+	for (const auto &itemId : ids) {
 		if (const auto item = _owner->message(itemId)) {
 			const auto history = item->history();
 			if (item->isScheduled()) {

Telegram/SourceFiles/data/data_replies_list.cpp

@@ -124,7 +124,7 @@ void RepliesList::appendLocalMessages(MessagesSlice &slice) {
 			return;
 		}
 		slice.ids.reserve(local.size());
-		for (const auto item : local) {
+		for (const auto &item : local) {
 			if (item->replyToTop() != _rootId) {
 				continue;
 			}
@@ -142,7 +142,7 @@ void RepliesList::appendLocalMessages(MessagesSlice &slice) {
 
 		dates.push_back(message->date());
 	}
-	for (const auto item : local) {
+	for (const auto &item : local) {
 		if (item->replyToTop() != _rootId) {
 			continue;
 		}
@@ -254,7 +254,7 @@ void RepliesList::injectRootMessage(not_null<Viewer*> viewer) {
 	injectRootDivider(root, slice);
 
 	if (const auto group = _history->owner().groups().find(root)) {
-		for (const auto item : ranges::views::reverse(group->items)) {
+		for (const auto &item : ranges::views::reverse(group->items)) {
 			slice->ids.push_back(item->fullId());
 		}
 		viewer->injectedForRoot = group->items.size();

Telegram/SourceFiles/data/data_scheduled_messages.cpp

@@ -495,7 +495,7 @@ void ScheduledMessages::updated(
 		const base::flat_set<not_null<HistoryItem*>> &added,
 		const base::flat_set<not_null<HistoryItem*>> &clear) {
 	if (!clear.empty()) {
-		for (const auto item : clear) {
+		for (const auto &item : clear) {
 			item->destroy();
 		}
 	}

Telegram/SourceFiles/data/data_session.cpp

@@ -1162,7 +1162,7 @@ void Session::setupUserIsContactViewer() {
 	}) | rpl::start_with_next([=](not_null<UserData*> user) {
 		const auto i = _contactViews.find(peerToUser(user->id));
 		if (i != _contactViews.end()) {
-			for (const auto view : i->second) {
+			for (const auto &view : i->second) {
 				requestViewResize(view);
 			}
 		}
@@ -1211,7 +1211,7 @@ void Session::documentLoadSettingsChanged() {
 
 void Session::notifyPhotoLayoutChanged(not_null<const PhotoData*> photo) {
 	if (const auto i = _photoItems.find(photo); i != end(_photoItems)) {
-		for (const auto item : i->second) {
+		for (const auto &item : i->second) {
 			notifyItemLayoutChange(item);
 		}
 	}
@@ -1220,7 +1220,7 @@ void Session::notifyPhotoLayoutChanged(not_null<const PhotoData*> photo) {
 void Session::requestPhotoViewRepaint(not_null<const PhotoData*> photo) {
 	const auto i = _photoItems.find(photo);
 	if (i != end(_photoItems)) {
-		for (const auto item : i->second) {
+		for (const auto &item : i->second) {
 			requestItemRepaint(item);
 		}
 	}
@@ -1230,13 +1230,13 @@ void Session::notifyDocumentLayoutChanged(
 		not_null<const DocumentData*> document) {
 	const auto i = _documentItems.find(document);
 	if (i != end(_documentItems)) {
-		for (const auto item : i->second) {
+		for (const auto &item : i->second) {
 			notifyItemLayoutChange(item);
 		}
 	}
 	if (const auto items = InlineBots::Layout::documentItems()) {
 		if (const auto i = items->find(document); i != items->end()) {
-			for (const auto item : i->second) {
+			for (const auto &item : i->second) {
 				item->layoutChanged();
 			}
 		}
@@ -1247,7 +1247,7 @@ void Session::requestDocumentViewRepaint(
 		not_null<const DocumentData*> document) {
 	const auto i = _documentItems.find(document);
 	if (i != end(_documentItems)) {
-		for (const auto item : i->second) {
+		for (const auto &item : i->second) {
 			requestItemRepaint(item);
 		}
 	}
@@ -1255,7 +1255,7 @@ void Session::requestDocumentViewRepaint(
 
 void Session::requestPollViewRepaint(not_null<const PollData*> poll) {
 	if (const auto i = _pollViews.find(poll); i != _pollViews.end()) {
-		for (const auto view : i->second) {
+		for (const auto &view : i->second) {
 			requestViewResize(view);
 		}
 	}
@@ -1500,7 +1500,7 @@ rpl::producer<not_null<History*>> Session::historyChanged() const {
 }
 
 void Session::sendHistoryChangeNotifications() {
-	for (const auto history : base::take(_historiesChanged)) {
+	for (const auto &history : base::take(_historiesChanged)) {
 		_historyChanged.fire_copy(history);
 	}
 }
@@ -1531,12 +1531,12 @@ void Session::unloadHeavyViewParts(
 		delegate,
 		[](not_null<ViewElement*> element) { return element->delegate(); });
 	if (remove == _heavyViewParts.size()) {
-		for (const auto view : base::take(_heavyViewParts)) {
+		for (const auto &view : base::take(_heavyViewParts)) {
 			view->unloadHeavyPart();
 		}
 	} else {
 		auto remove = std::vector<not_null<ViewElement*>>();
-		for (const auto view : _heavyViewParts) {
+		for (const auto &view : _heavyViewParts) {
 			if (view->delegate() == delegate) {
 				remove.push_back(view);
 			}
@@ -1555,7 +1555,7 @@ void Session::unloadHeavyViewParts(
 		return;
 	}
 	auto remove = std::vector<not_null<ViewElement*>>();
-	for (const auto view : _heavyViewParts) {
+	for (const auto &view : _heavyViewParts) {
 		if (view->delegate() == delegate
 			&& !delegate->elementIntersectsRange(view, from, till)) {
 			remove.push_back(view);
@@ -1942,7 +1942,7 @@ void Session::processMessagesDeleted(
 	}
 
 	auto historiesToCheck = base::flat_set<not_null<History*>>();
-	for (const auto messageId : data) {
+	for (const auto &messageId : data) {
 		const auto i = list ? list->find(messageId.v) : Messages::iterator();
 		if (list && i != list->end()) {
 			const auto history = i->second->history();
@@ -1954,7 +1954,7 @@ void Session::processMessagesDeleted(
 			affected->unknownMessageDeleted(messageId.v);
 		}
 	}
-	for (const auto history : historiesToCheck) {
+	for (const auto &history : historiesToCheck) {
 		history->requestChatListMessage();
 	}
 }
@@ -1967,7 +1967,7 @@ void Session::removeDependencyMessage(not_null<HistoryItem*> item) {
 	const auto items = std::move(i->second);
 	_dependentMessages.erase(i);
 
-	for (const auto dependent : items) {
+	for (const auto &dependent : items) {
 		dependent->dependencyItemRemoved(item);
 	}
 }
@@ -2030,7 +2030,7 @@ HistoryItem *Session::message(FullMsgId itemId) const {
 void Session::updateDependentMessages(not_null<HistoryItem*> item) {
 	const auto i = _dependentMessages.find(item);
 	if (i != end(_dependentMessages)) {
-		for (const auto dependent : i->second) {
+		for (const auto &dependent : i->second) {
 			dependent->updateDependencyItem();
 		}
 	}
@@ -3169,7 +3169,7 @@ void Session::applyUpdate(const MTPDupdateChatParticipants &update) {
 	});
 	if (const auto chat = chatLoaded(chatId)) {
 		ApplyChatUpdate(chat, update);
-		for (const auto user : chat->participants) {
+		for (const auto &user : chat->participants) {
 			if (user->isBot() && !user->botInfo->inited) {
 				_session->api().requestFullPeer(user);
 			}
@@ -3434,7 +3434,7 @@ void Session::documentMessageRemoved(not_null<DocumentData*> document) {
 
 void Session::checkPlayingAnimations() {
 	auto check = base::flat_set<not_null<ViewElement*>>();
-	for (const auto view : _heavyViewParts) {
+	for (const auto &view : _heavyViewParts) {
 		if (const auto media = view->media()) {
 			if (const auto document = media->getDocument()) {
 				if (document->isAnimation() || document->isVideoFile()) {
@@ -3447,7 +3447,7 @@ void Session::checkPlayingAnimations() {
 			}
 		}
 	}
-	for (const auto view : check) {
+	for (const auto &view : check) {
 		view->media()->checkAnimation();
 	}
 }
@@ -3455,7 +3455,7 @@ void Session::checkPlayingAnimations() {
 HistoryItem *Session::findWebPageItem(not_null<WebPageData*> page) const {
 	const auto i = _webpageItems.find(page);
 	if (i != _webpageItems.end()) {
-		for (const auto item : i->second) {
+		for (const auto &item : i->second) {
 			if (IsServerMsgId(item->id)) {
 				return item;
 			}
@@ -3514,25 +3514,25 @@ void Session::notifyPollUpdateDelayed(not_null<PollData*> poll) {
 }
 
 void Session::sendWebPageGamePollNotifications() {
-	for (const auto page : base::take(_webpagesUpdated)) {
+	for (const auto &page : base::take(_webpagesUpdated)) {
 		_webpageUpdates.fire_copy(page);
 		const auto i = _webpageViews.find(page);
 		if (i != _webpageViews.end()) {
-			for (const auto view : i->second) {
+			for (const auto &view : i->second) {
 				requestViewResize(view);
 			}
 		}
 	}
-	for (const auto game : base::take(_gamesUpdated)) {
+	for (const auto &game : base::take(_gamesUpdated)) {
 		if (const auto i = _gameViews.find(game); i != _gameViews.end()) {
-			for (const auto view : i->second) {
+			for (const auto &view : i->second) {
 				requestViewResize(view);
 			}
 		}
 	}
-	for (const auto poll : base::take(_pollsUpdated)) {
+	for (const auto &poll : base::take(_pollsUpdated)) {
 		if (const auto i = _pollViews.find(poll); i != _pollViews.end()) {
-			for (const auto view : i->second) {
+			for (const auto &view : i->second) {
 				requestViewResize(view);
 			}
 		}

Telegram/SourceFiles/data/stickers/data_stickers.cpp

@@ -166,7 +166,7 @@ void Stickers::incrementSticker(not_null<DocumentData*> document) {
 		}
 		set->stickers.push_front(document);
 		if (const auto emojiList = getEmojiListFromSet(document)) {
-			for (const auto emoji : *emojiList) {
+			for (const auto &emoji : *emojiList) {
 				set->emoji[emoji].push_front(document);
 			}
 		} else if (!removedFromEmoji.empty()) {

Telegram/SourceFiles/dialogs/dialogs_indexed_list.cpp

@@ -26,7 +26,7 @@ RowsByLetter IndexedList::addToEnd(Key key) {
 	}
 
 	auto result = RowsByLetter{ _list.addToEnd(key) };
-	for (const auto ch : key.entry()->chatListFirstLetters()) {
+	for (const auto &ch : key.entry()->chatListFirstLetters()) {
 		auto j = _index.find(ch);
 		if (j == _index.cend()) {
 			j = _index.emplace(ch, _sortMode, _filterId).first;
@@ -42,7 +42,7 @@ Row *IndexedList::addByName(Key key) {
 	}
 
 	const auto result = _list.addByName(key);
-	for (const auto ch : key.entry()->chatListFirstLetters()) {
+	for (const auto &ch : key.entry()->chatListFirstLetters()) {
 		auto j = _index.find(ch);
 		if (j == _index.cend()) {
 			j = _index.emplace(ch, _sortMode, _filterId).first;
@@ -63,7 +63,7 @@ void IndexedList::adjustByDate(const RowsByLetter &links) {
 
 void IndexedList::moveToTop(Key key) {
 	if (_list.moveToTop(key)) {
-		for (const auto ch : key.entry()->chatListFirstLetters()) {
+		for (const auto &ch : key.entry()->chatListFirstLetters()) {
 			if (auto it = _index.find(ch); it != _index.cend()) {
 				it->second.moveToTop(key);
 			}
@@ -121,7 +121,7 @@ void IndexedList::adjustByName(
 
 	auto toRemove = oldLetters;
 	auto toAdd = base::flat_set<QChar>();
-	for (const auto ch : key.entry()->chatListFirstLetters()) {
+	for (const auto &ch : key.entry()->chatListFirstLetters()) {
 		auto j = toRemove.find(ch);
 		if (j == toRemove.cend()) {
 			toAdd.insert(ch);
@@ -158,7 +158,7 @@ void IndexedList::adjustNames(
 
 	auto toRemove = oldLetters;
 	auto toAdd = base::flat_set<QChar>();
-	for (const auto ch : key.entry()->chatListFirstLetters()) {
+	for (const auto &ch : key.entry()->chatListFirstLetters()) {
 		auto j = toRemove.find(ch);
 		if (j == toRemove.cend()) {
 			toAdd.insert(ch);
@@ -188,7 +188,7 @@ void IndexedList::adjustNames(
 
 void IndexedList::del(Key key, Row *replacedBy) {
 	if (_list.del(key, replacedBy)) {
-		for (const auto ch : key.entry()->chatListFirstLetters()) {
+		for (const auto &ch : key.entry()->chatListFirstLetters()) {
 			if (auto it = _index.find(ch); it != _index.cend()) {
 				it->second.del(key, replacedBy);
 			}
@@ -225,7 +225,7 @@ std::vector<not_null<Row*>> IndexedList::filtered(
 		return result;
 	}
 	result.reserve(minimal->size());
-	for (const auto row : *minimal) {
+	for (const auto &row : *minimal) {
 		const auto &nameWords = row->entry()->chatListNameWords();
 		const auto found = [&](const QString &word) {
 			for (const auto &name : nameWords) {

Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp

@@ -61,7 +61,7 @@ constexpr auto kStartReorderThreshold = 30;
 
 int FixedOnTopDialogsCount(not_null<Dialogs::IndexedList*> list) {
 	auto result = 0;
-	for (const auto row : *list) {
+	for (const auto &row : *list) {
 		if (!row->entry()->fixedOnTopIndex()) {
 			break;
 		}
@@ -74,7 +74,7 @@ int PinnedDialogsCount(
 		FilterId filterId,
 		not_null<Dialogs::IndexedList*> list) {
 	auto result = 0;
-	for (const auto row : *list) {
+	for (const auto &row : *list) {
 		if (row->entry()->fixedOnTopIndex()) {
 			continue;
 		} else if (!row->entry()->isPinnedDialog(filterId)) {
@@ -341,7 +341,7 @@ int InnerWidget::dialogsOffset() const {
 
 int InnerWidget::fixedOnTopCount() const {
 	auto result = 0;
-	for (const auto row : *shownDialogs()) {
+	for (const auto &row : *shownDialogs()) {
 		if (row->entry()->fixedOnTopIndex()) {
 			++result;
 		} else {
@@ -1103,7 +1103,7 @@ int InnerWidget::countPinnedIndex(Row *ofRow) {
 		return -1;
 	}
 	auto result = 0;
-	for (const auto row : *shownDialogs()) {
+	for (const auto &row : *shownDialogs()) {
 		if (row->entry()->fixedOnTopIndex()) {
 			continue;
 		} else if (!row->entry()->isPinnedDialog(_filterId)) {

Telegram/SourceFiles/export/output/export_output_html.cpp

@@ -397,7 +397,7 @@ QByteArray PeersMap::wrapUserName(UserId userId) const {
 
 QByteArray PeersMap::wrapUserNames(const std::vector<UserId> &data) const {
 	auto list = std::vector<QByteArray>();
-	for (const auto userId : data) {
+	for (const auto &userId : data) {
 		list.push_back(wrapUserName(userId));
 	}
 	return SerializeList(list);

Telegram/SourceFiles/export/output/export_output_json.cpp

@@ -324,7 +324,7 @@ QByteArray SerializeMessage(
 			const std::vector<UserId> &data,
 			const QByteArray &label = "members") {
 		auto list = std::vector<QByteArray>();
-		for (const auto userId : data) {
+		for (const auto &userId : data) {
 			list.push_back(wrapUserName(userId));
 		}
 		pushBare(label, SerializeArray(context, list));

Telegram/SourceFiles/history/admin_log/history_admin_log_filter.cpp

@@ -299,7 +299,7 @@ void FilterBox::Inner::createAllUsersCheckbox(const FilterValue &filter) {
 }
 
 void FilterBox::Inner::createAdminsCheckboxes(const std::vector<not_null<UserData*>> &admins, const FilterValue &filter) {
-	for (const auto user : admins) {
+	for (const auto &user : admins) {
 		const auto checked = filter.allUsers || base::contains(filter.admins, user);
 		const auto checkbox = addRow(
 			object_ptr<UserCheckbox>(this, user, checked),

Telegram/SourceFiles/history/history.cpp

@@ -1236,7 +1236,7 @@ void History::addOlderSlice(const QVector<MTPMessage> &slice) {
 
 	if (const auto added = createItems(slice); !added.empty()) {
 		startBuildingFrontBlock(added.size());
-		for (const auto item : added) {
+		for (const auto &item : added) {
 			addItemToBlock(item);
 		}
 		finishBuildingFrontBlock();
@@ -1269,7 +1269,7 @@ void History::addNewerSlice(const QVector<MTPMessage> &slice) {
 	if (const auto added = createItems(slice); !added.empty()) {
 		Assert(!isBuildingFrontBlock());
 
-		for (const auto item : added) {
+		for (const auto &item : added) {
 			addItemToBlock(item);
 		}
 
@@ -1315,7 +1315,7 @@ void History::addItemsToLists(
 		// lastParticipants are displayed in Profile as members list.
 		markupSenders = &peer->asChannel()->mgInfo->markupSenders;
 	}
-	for (const auto item : ranges::views::reverse(items)) {
+	for (const auto &item : ranges::views::reverse(items)) {
 		item->addToUnreadMentions(UnreadMentionType::Existing);
 		if (item->from()->id) {
 			if (lastAuthors) { // chats
@@ -1389,7 +1389,7 @@ void History::checkAddAllToUnreadMentions() {
 void History::addToSharedMedia(
 		const std::vector<not_null<HistoryItem*>> &items) {
 	std::vector<MsgId> medias[Storage::kSharedMediaTypeCount];
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (const auto types = item->sharedMediaTypes()) {
 			for (auto i = 0; i != Storage::kSharedMediaTypeCount; ++i) {
 				const auto type = static_cast<Storage::SharedMediaType>(i);
@@ -1459,7 +1459,7 @@ bool History::readInboxTillNeedsRequest(MsgId tillId) {
 
 void History::readClientSideMessages() {
 	auto &histories = owner().histories();
-	for (const auto item : _localMessages) {
+	for (const auto &item : _localMessages) {
 		histories.readClientSideMessage(item);
 	}
 }
@@ -3040,12 +3040,12 @@ void History::clear(ClearType type) {
 	} else {
 		// Leave the 'sending' messages in local messages.
 		auto local = base::flat_set<not_null<HistoryItem*>>();
-		for (const auto item : _localMessages) {
+		for (const auto &item : _localMessages) {
 			if (!item->isSending()) {
 				local.emplace(item);
 			}
 		}
-		for (const auto item : local) {
+		for (const auto &item : local) {
 			item->destroy();
 		}
 		_notifications.clear();

Telegram/SourceFiles/history/history_inner_widget.cpp

@@ -2090,7 +2090,7 @@ TextForMimeData HistoryInner::getSelectedText() const {
 		wrapItem(group->items.back(), HistoryGroupText(group));
 	};
 
-	for (const auto [item, selection] : selected) {
+	for (const auto &[item, selection] : selected) {
 		if (const auto group = session().data().groups().find(item)) {
 			if (groups.contains(group)) {
 				continue;
@@ -3183,7 +3183,7 @@ bool HistoryInner::isSelected(
 bool HistoryInner::isSelectedGroup(
 		not_null<SelectedItems*> toItems,
 		not_null<const Data::Group*> group) const {
-	for (const auto other : group->items) {
+	for (const auto &other : group->items) {
 		if (!isSelected(toItems, other)) {
 			return false;
 		}
@@ -3272,7 +3272,7 @@ void HistoryInner::changeSelectionAsGroup(
 	}
 	auto total = int(toItems->size());
 	const auto canSelect = [&] {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			if (!goodForSelection(toItems, other, total)) {
 				return false;
 			}
@@ -3280,11 +3280,11 @@ void HistoryInner::changeSelectionAsGroup(
 		return (total <= MaxSelectedItems);
 	}();
 	if (action == SelectAction::Select && canSelect) {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			addToSelection(toItems, other);
 		}
 	} else {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			removeFromSelection(toItems, other);
 		}
 	}

Telegram/SourceFiles/history/history_message.cpp

@@ -104,7 +104,7 @@ namespace {
 }
 
 [[nodiscard]] bool HasInlineItems(const HistoryItemsList &items) {
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (item->viaBot()) {
 			return true;
 		}
@@ -131,7 +131,7 @@ QString GetErrorTextForSending(
 		return tr::lng_forward_cant(tr::now);
 	}
 
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (const auto media = item->media()) {
 			const auto error = media->errorTextForForward(peer);
 			if (!error.isEmpty() && error != qstr("skip")) {
@@ -161,7 +161,7 @@ QString GetErrorTextForSending(
 		} else if (items.size() > 1) {
 			const auto albumForward = [&] {
 				if (const auto groupId = items.front()->groupId()) {
-					for (const auto item : items) {
+					for (const auto &item : items) {
 						if (item->groupId() != groupId) {
 							return false;
 						}
@@ -276,7 +276,7 @@ void FastShareMessage(not_null<HistoryItem*> item) {
 				: MTPmessages_ForwardMessages::Flag(0));
 		auto msgIds = QVector<MTPint>();
 		msgIds.reserve(data->msgIds.size());
-		for (const auto fullId : data->msgIds) {
+		for (const auto &fullId : data->msgIds) {
 			msgIds.push_back(MTP_int(fullId.msg));
 		}
 		auto generateRandom = [&] {

Telegram/SourceFiles/history/history_service.cpp

@@ -382,7 +382,7 @@ void HistoryService::setMessageByAction(const MTPmessageAction &action) {
 		const auto callId = CallIdFromInput(action.vcall());
 		const auto owner = &history()->owner();
 		const auto peer = history()->peer;
-		for (const auto id : action.vusers().v) {
+		for (const auto &id : action.vusers().v) {
 			const auto user = owner->user(id.v);
 			if (callId) {
 				owner->registerInvitedToCallUser(callId, peer, user);

Telegram/SourceFiles/history/history_widget.cpp

@@ -5002,7 +5002,7 @@ void HistoryWidget::revealItemsCallback() {
 }
 
 void HistoryWidget::startItemRevealAnimations() {
-	for (const auto item : base::take(_itemRevealPending)) {
+	for (const auto &item : base::take(_itemRevealPending)) {
 		if (const auto view = item->mainView()) {
 			if (const auto top = _list->itemTop(view); top >= 0) {
 				if (const auto height = view->height()) {

Telegram/SourceFiles/history/view/history_view_list_widget.cpp

@@ -884,7 +884,7 @@ bool ListWidget::overSelectedItems() const {
 bool ListWidget::isSelectedGroup(
 		const SelectedMap &applyTo,
 		not_null<const Data::Group*> group) const {
-	for (const auto other : group->items) {
+	for (const auto &other : group->items) {
 		if (!applyTo.contains(other->fullId())) {
 			return false;
 		}
@@ -970,7 +970,7 @@ void ListWidget::changeSelectionAsGroup(
 	}
 	auto already = int(applyTo.size());
 	const auto canSelect = [&] {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			if (!isGoodForSelection(applyTo, other, already)) {
 				return false;
 			}
@@ -978,11 +978,11 @@ void ListWidget::changeSelectionAsGroup(
 		return true;
 	}();
 	if (action == SelectAction::Select && canSelect) {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			addToSelection(applyTo, other);
 		}
 	} else {
-		for (const auto other : group->items) {
+		for (const auto &other : group->items) {
 			removeFromSelection(applyTo, other->fullId());
 		}
 	}
@@ -1440,7 +1440,7 @@ void ListWidget::resizeToWidth(int newWidth, int minHeight) {
 }
 
 void ListWidget::startItemRevealAnimations() {
-	for (const auto view : base::take(_itemRevealPending)) {
+	for (const auto &view : base::take(_itemRevealPending)) {
 		if (const auto height = view->height()) {
 			if (!_itemRevealAnimations.contains(view)) {
 				auto &animation = _itemRevealAnimations[view];
@@ -1731,7 +1731,7 @@ void ListWidget::applyDragSelection() {
 
 void ListWidget::applyDragSelection(SelectedMap &applyTo) const {
 	if (_dragSelectAction == DragSelectAction::Selecting) {
-		for (const auto itemId : _dragSelected) {
+		for (const auto &itemId : _dragSelected) {
 			if (applyTo.size() >= MaxSelectedItems) {
 				break;
 			} else if (!applyTo.contains(itemId)) {
@@ -1741,7 +1741,7 @@ void ListWidget::applyDragSelection(SelectedMap &applyTo) const {
 			}
 		}
 	} else if (_dragSelectAction == DragSelectAction::Deselecting) {
-		for (const auto itemId : _dragSelected) {
+		for (const auto &itemId : _dragSelected) {
 			removeFromSelection(applyTo, itemId);
 		}
 	}
@@ -2163,12 +2163,12 @@ void ListWidget::updateDragSelection(
 	};
 	const auto changeGroup = [&](not_null<HistoryItem*> item, bool add) {
 		if (const auto group = groups.find(item)) {
-			for (const auto item : group->items) {
+			for (const auto &item : group->items) {
 				if (!_delegate->listIsItemGoodForSelection(item)) {
 					return;
 				}
 			}
-			for (const auto item : group->items) {
+			for (const auto &item : group->items) {
 				changeItem(item, add);
 			}
 		} else if (_delegate->listIsItemGoodForSelection(item)) {

Telegram/SourceFiles/history/view/history_view_pinned_section.cpp

@@ -622,7 +622,7 @@ bool PinnedWidget::listIsLessInOrder(
 void PinnedWidget::listSelectionChanged(SelectedItems &&items) {
 	HistoryView::TopBarWidget::SelectedState state;
 	state.count = items.size();
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (item.canDelete) {
 			++state.canDeleteCount;
 		}

Telegram/SourceFiles/history/view/history_view_replies_section.cpp

@@ -1785,7 +1785,7 @@ bool RepliesWidget::listIsLessInOrder(
 void RepliesWidget::listSelectionChanged(SelectedItems &&items) {
 	HistoryView::TopBarWidget::SelectedState state;
 	state.count = items.size();
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (item.canDelete) {
 			++state.canDeleteCount;
 		}

Telegram/SourceFiles/history/view/history_view_scheduled_section.cpp

@@ -1150,7 +1150,7 @@ bool ScheduledWidget::listIsLessInOrder(
 void ScheduledWidget::listSelectionChanged(SelectedItems &&items) {
 	HistoryView::TopBarWidget::SelectedState state;
 	state.count = items.size();
-	for (const auto item : items) {
+	for (const auto &item : items) {
 		if (item.canDelete) {
 			++state.canDeleteCount;
 		}

Telegram/SourceFiles/history/view/history_view_top_bar_widget.cpp

@@ -1018,7 +1018,7 @@ void TopBarWidget::updateOnlineDisplay() {
 			const auto self = session().user();
 			auto online = 0;
 			auto onlyMe = true;
-			for (const auto user : chat->participants) {
+			for (const auto &user : chat->participants) {
 				if (user->onlineTill > now) {
 					++online;
 					if (onlyMe && user != self) onlyMe = false;
@@ -1095,7 +1095,7 @@ void TopBarWidget::updateOnlineDisplayTimer() {
 	if (const auto user = peer->asUser()) {
 		handleUser(user);
 	} else if (const auto chat = peer->asChat()) {
-		for (const auto user : chat->participants) {
+		for (const auto &user : chat->participants) {
 			handleUser(user);
 		}
 	} else if (peer->isChannel()) {

Telegram/SourceFiles/history/view/media/history_view_poll.cpp

@@ -752,7 +752,7 @@ void Poll::draw(Painter &p, const PaintContext &context) const {
 	auto &&answers = ranges::views::zip(
 		_answers,
 		ranges::views::ints(0, int(_answers.size())));
-	for (const auto &[answer, index] : answers) {
+	for (const auto [answer, index] : answers) {
 		const auto animation = _answersAnimation
 			? &_answersAnimation->data[index]
 			: nullptr;

Telegram/SourceFiles/history/view/media/history_view_web_page.cpp

@@ -56,7 +56,7 @@ std::vector<std::unique_ptr<Data::Media>> PrepareCollageMedia(
 		const WebPageCollage &data) {
 	auto result = std::vector<std::unique_ptr<Data::Media>>();
 	result.reserve(data.items.size());
-	for (const auto item : data.items) {
+	for (const auto &item : data.items) {
 		if (const auto document = std::get_if<DocumentData*>(&item)) {
 			result.push_back(std::make_unique<Data::MediaFile>(
 				parent,

Telegram/SourceFiles/info/profile/info_profile_values.cpp

@@ -266,7 +266,7 @@ rpl::producer<int> AdminsCountValue(not_null<PeerData*> peer) {
 rpl::producer<int> RestrictionsCountValue(not_null<PeerData*> peer) {
 	const auto countOfRestrictions = [](ChatRestrictions restrictions) {
 		auto count = 0;
-		for (const auto f : Data::ListOfRestrictions()) {
+		for (const auto &f : Data::ListOfRestrictions()) {
 			if (restrictions & f) count++;
 		}
 		return int(Data::ListOfRestrictions().size()) - count;

Telegram/SourceFiles/lang/lang_tag.cpp

@@ -903,7 +903,7 @@ QString FormatDouble(float64 value) {
 
 int NonZeroPartToInt(QString value) {
 	auto zeros = 0;
-	for (const auto ch : value) {
+	for (const auto &ch : value) {
 		if (ch == '0') {
 			++zeros;
 		} else {
@@ -988,7 +988,7 @@ void UpdatePluralRules(const QString &languageId) {
 	static auto kMap = GeneratePluralRulesMap();
 	auto parent = uint64(0);
 	auto key = uint64(0);
-	for (const auto ch : languageId) {
+	for (const auto &ch : languageId) {
 		const auto converted = ConvertKeyChar(ch.unicode());
 		if (converted == '-' && !parent) {
 			parent = key;

Telegram/SourceFiles/main/main_session_settings.cpp

@@ -48,7 +48,7 @@ QByteArray SessionSettings::serialize() const {
 		stream << qint32(kVersionTag) << qint32(kVersion);
 		stream << static_cast<qint32>(_selectorTab);
 		stream << qint32(_groupStickersSectionHidden.size());
-		for (const auto peerId : _groupStickersSectionHidden) {
+		for (const auto &peerId : _groupStickersSectionHidden) {
 			stream << SerializePeerId(peerId);
 		}
 		stream << qint32(_supportSwitch);

Telegram/SourceFiles/mainwidget.cpp

@@ -818,7 +818,7 @@ void MainWidget::handleAudioUpdate(const Media::Player::TrackState &state) {
 	if (document) {
 		if (const auto items = InlineBots::Layout::documentItems()) {
 			if (const auto i = items->find(document); i != items->end()) {
-				for (const auto item : i->second) {
+				for (const auto &item : i->second) {
 					item->update();
 				}
 			}

Telegram/SourceFiles/media/view/media_view_overlay_raster.cpp

@@ -38,7 +38,7 @@ void OverlayWidget::RendererSW::paintBackground() {
 	const auto &bg = _owner->_fullScreenVideo
 		? st::mediaviewVideoBg
 		: st::mediaviewBg;
-	for (const auto rect : region) {
+	for (const auto &rect : region) {
 		_p->fillRect(rect, bg);
 	}
 	_p->setCompositionMode(m);

Telegram/SourceFiles/passport/passport_encryption.cpp

@@ -268,7 +268,7 @@ std::vector<DataError> DeserializeErrors(bytes::const_span json) {
 	}
 	auto array = document.array();
 	auto result = std::vector<DataError>();
-	for (const auto &error : array) {
+	for (const auto error : array) {
 		if (!error.isObject()) {
 			LOG(("API Error: Not an object inside errors JSON."));
 			continue;

Telegram/SourceFiles/passport/passport_form_controller.cpp

@@ -2544,7 +2544,7 @@ bool FormController::parseForm(const MTPaccount_AuthorizationForm &result) {
 	}
 	for (const auto &required : data.vrequired_types().v) {
 		const auto row = CollectRequestedRow(required);
-		for (const auto requested : row.values) {
+		for (const auto &requested : row.values) {
 			const auto type = requested.type;
 			const auto [i, ok] = _form.values.emplace(type, Value(type));
 			auto &value = i->second;

Telegram/SourceFiles/payments/ui/payments_form_summary.cpp

@@ -458,7 +458,7 @@ void FormSummary::setupSuggestedTips(not_null<VerticalLayout*> layout) {
 			}
 			height += buttons[0].widget->height() + skip;
 		};
-		for (const auto button : buttons) {
+		for (const auto &button : buttons) {
 			if (button.minWidth <= left) {
 				left -= button.minWidth + skip;
 				++rowEnd;

Telegram/SourceFiles/platform/mac/touchbar/items/mac_scrubber_item.mm

@@ -237,7 +237,7 @@ void AppendRecentStickers(
 			to.emplace_back(PickerScrubberItem(document));
 		}
 	}
-	for (const auto recent : recentPack) {
+	for (const auto &recent : recentPack) {
 		to.emplace_back(PickerScrubberItem(recent.first));
 	}
 }

Telegram/SourceFiles/profile/profile_block_group_members.cpp

@@ -281,7 +281,7 @@ void GroupMembersWidget::fillChatMembers(not_null<ChatData*> chat) {
 	reserveItemsForSize(chat->participants.size());
 	addUser(chat, chat->session().user())->onlineForSort
 		= std::numeric_limits<TimeId>::max();
-	for (const auto user : chat->participants) {
+	for (const auto &user : chat->participants) {
 		if (!user->isSelf()) {
 			addUser(chat, user);
 		}

Telegram/SourceFiles/support/support_templates.cpp

@@ -41,7 +41,7 @@ bool IsTemplatesFile(const QString &file) {
 QString NormalizeQuestion(const QString &question) {
 	auto result = QString();
 	result.reserve(question.size());
-	for (const auto ch : question) {
+	for (const auto &ch : question) {
 		if (ch.isLetterOrNumber()) {
 			result.append(ch.toLower());
 		}

Telegram/SourceFiles/ui/boxes/country_select_box.cpp

@@ -233,7 +233,7 @@ void CountrySelectBox::Inner::init() {
 		}
 	}
 	auto index = 0;
-	for (const auto info : _list) {
+	for (const auto &info : _list) {
 		auto full = info.country
 			+ ' '
 			+ (!info.alternativeName.isEmpty()

Telegram/SourceFiles/ui/boxes/single_choice_box.cpp

@@ -29,7 +29,7 @@ void SingleChoiceBox(
 		layout,
 		st::boxOptionListPadding.top() + st::autolockButton.margin.top()));
 	auto &&ints = ranges::views::ints(0, ranges::unreachable);
-	for (const auto &[i, text] : ranges::views::zip(ints, args.options)) {
+	for (const auto [i, text] : ranges::views::zip(ints, args.options)) {
 		layout->add(
 			object_ptr<Ui::Radiobutton>(
 				layout,

Telegram/SourceFiles/window/themes/window_theme_editor_block.cpp

@@ -257,7 +257,7 @@ void EditorBlock::addToSearch(const Row &row) {
 	if (!query.isEmpty()) resetSearch();
 
 	auto index = findRowIndex(&row);
-	for (const auto ch : row.searchStartChars()) {
+	for (const auto &ch : row.searchStartChars()) {
 		_searchIndex[ch].insert(index);
 	}
 
@@ -269,7 +269,7 @@ void EditorBlock::removeFromSearch(const Row &row) {
 	if (!query.isEmpty()) resetSearch();
 
 	auto index = findRowIndex(&row);
-	for (const auto ch : row.searchStartChars()) {
+	for (const auto &ch : row.searchStartChars()) {
 		const auto i = _searchIndex.find(ch);
 		if (i != end(_searchIndex)) {
 			i->second.remove(index);