diff --git a/benchmark/bench_db.cpp b/benchmark/bench_db.cpp
index 27a42d09f..96a3a1c32 100644
--- a/benchmark/bench_db.cpp
+++ b/benchmark/bench_db.cpp
@@ -95,7 +95,7 @@ class SqliteKVBench : public td::Benchmark {
     td::string path = "testdb.sqlite";
     td::SqliteDb::destroy(path).ignore();
     if (is_encrypted) {
-      td::SqliteDb::change_key(path, td::DbKey::password("cucumber"), td::DbKey::empty());
+      td::SqliteDb::change_key(path, td::DbKey::password("cucumber"), td::DbKey::empty()).ensure();
       db = td::SqliteDb::open_with_key(path, td::DbKey::password("cucumber")).move_as_ok();
     } else {
       db = td::SqliteDb::open_with_key(path, td::DbKey::empty()).move_as_ok();
diff --git a/td/mtproto/RawConnection.cpp b/td/mtproto/RawConnection.cpp
index 2eb7960cf..8c81bf6eb 100644
--- a/td/mtproto/RawConnection.cpp
+++ b/td/mtproto/RawConnection.cpp
@@ -85,7 +85,7 @@ Status RawConnection::flush_read(const AuthKey &auth_key, Callback &callback) {
     }
 
     if (quick_ack != 0) {
-      on_quick_ack(quick_ack, callback);
+      TRY_STATUS(on_quick_ack(quick_ack, callback));
       continue;
     }
 
@@ -146,7 +146,7 @@ Status RawConnection::on_quick_ack(uint32 quick_ack, Callback &callback) {
   }
   auto token = it->second;
   quick_ack_to_token_.erase(it);
-  callback.on_quick_ack(token);
+  callback.on_quick_ack(token).ignore();
   return Status::OK();
 }
 
diff --git a/td/telegram/SecretChatActor.cpp b/td/telegram/SecretChatActor.cpp
index e3138af47..d3b1e1ca0 100644
--- a/td/telegram/SecretChatActor.cpp
+++ b/td/telegram/SecretChatActor.cpp
@@ -1196,7 +1196,7 @@ void SecretChatActor::update_seq_no_state(const T &new_seq_no_state) {
   return on_seq_no_state_changed();
 }
 
-Status SecretChatActor::do_inbound_message_decrypted_pending(unique_ptr<logevent::InboundSecretMessage> message) {
+void SecretChatActor::do_inbound_message_decrypted_pending(unique_ptr<logevent::InboundSecretMessage> message) {
   // Just save logevent if necessary
   auto logevent_id = message->logevent_id();
 
@@ -1217,8 +1217,6 @@ Status SecretChatActor::do_inbound_message_decrypted_pending(unique_ptr<logevent
 
   auto seq_no = message->decrypted_message_layer->out_seq_no_ / 2;
   pending_inbound_messages_[seq_no] = std::move(message);
-
-  return Status::OK();
 }
 
 Status SecretChatActor::do_inbound_message_decrypted(unique_ptr<logevent::InboundSecretMessage> message) {
diff --git a/td/telegram/SecretChatActor.h b/td/telegram/SecretChatActor.h
index dddeaae72..abf471cd4 100644
--- a/td/telegram/SecretChatActor.h
+++ b/td/telegram/SecretChatActor.h
@@ -550,7 +550,7 @@ class SecretChatActor : public NetQueryCallback {
   Status do_inbound_message_encrypted(unique_ptr<logevent::InboundSecretMessage> message);
   Status do_inbound_message_decrypted_unchecked(unique_ptr<logevent::InboundSecretMessage> message);
   Status do_inbound_message_decrypted(unique_ptr<logevent::InboundSecretMessage> message);
-  Status do_inbound_message_decrypted_pending(unique_ptr<logevent::InboundSecretMessage> message);
+  void do_inbound_message_decrypted_pending(unique_ptr<logevent::InboundSecretMessage> message);
 
   void on_inbound_save_message_finish(uint64 state_id);
   void on_inbound_save_changes_finish(uint64 state_id);
diff --git a/td/telegram/SecureStorage.cpp b/td/telegram/SecureStorage.cpp
index 8a6de60eb..04dca6103 100644
--- a/td/telegram/SecureStorage.cpp
+++ b/td/telegram/SecureStorage.cpp
@@ -64,10 +64,10 @@ static Status data_view_for_each(const DataView &data, F &&f) {
 Result<ValueHash> calc_value_hash(const DataView &data_view) {
   Sha256State state;
   sha256_init(&state);
-  data_view_for_each(data_view, [&state](BufferSlice bytes) {
+  TRY_STATUS(data_view_for_each(data_view, [&state](BufferSlice bytes) {
     sha256_update(bytes.as_slice(), &state);
     return Status::OK();
-  });
+  }));
   UInt256 res;
   sha256_final(&state, as_slice(res));
   return ValueHash{res};
diff --git a/td/telegram/Td.cpp b/td/telegram/Td.cpp
index 84804767e..342ab0d79 100644
--- a/td/telegram/Td.cpp
+++ b/td/telegram/Td.cpp
@@ -3914,7 +3914,7 @@ void Td::close_impl(bool destroy_flag) {
   if (state_ == State::Decrypt) {
     clear_requests();
     if (destroy_flag) {
-      TdDb::destroy(parameters_);
+      TdDb::destroy(parameters_).ignore();
     }
     state_ = State::Close;
     close_flag_ = 4;
diff --git a/td/telegram/files/FileBitmask.cpp b/td/telegram/files/FileBitmask.cpp
index a6a0078ca..395e44f89 100644
--- a/td/telegram/files/FileBitmask.cpp
+++ b/td/telegram/files/FileBitmask.cpp
@@ -130,7 +130,7 @@ void Bitmask::set(int64 offset_part) {
 }
 
 int64 Bitmask::size() const {
-  return static_cast<int64>(data_.size() * 8);
+  return static_cast<int64>(data_.size()) * 8;
 }
 
 StringBuilder &operator<<(StringBuilder &sb, const Bitmask &mask) {
diff --git a/td/telegram/files/FileManager.cpp b/td/telegram/files/FileManager.cpp
index 86d9f6973..a32215276 100644
--- a/td/telegram/files/FileManager.cpp
+++ b/td/telegram/files/FileManager.cpp
@@ -1738,13 +1738,13 @@ void FileManager::load_from_pmc(FileNodePtr node, bool new_remote, bool new_loca
     return Status::OK();
   };
   if (new_remote) {
-    load(remote);
+    load(remote).ignore();
   }
   if (new_local) {
-    load(local);
+    load(local).ignore();
   }
   if (new_generate) {
-    load(generate);
+    load(generate).ignore();
   }
 }
 
diff --git a/td/telegram/files/FileStatsWorker.cpp b/td/telegram/files/FileStatsWorker.cpp
index 01cfb99f7..fbe706db9 100644
--- a/td/telegram/files/FileStatsWorker.cpp
+++ b/td/telegram/files/FileStatsWorker.cpp
@@ -48,7 +48,7 @@ struct DbFileInfo {
 
 // long and blocking
 template <class CallbackT>
-Status scan_db(CallbackT &&callback) {
+void scan_db(CallbackT &&callback) {
   G()->td_db()->get_file_db_shared()->pmc().get_by_range("file0", "file:", [&](Slice key, Slice value) {
     // skip reference to other data
     if (value.substr(0, 2) == "@@") {
@@ -84,7 +84,6 @@ Status scan_db(CallbackT &&callback) {
     }
     callback(info);
   });
-  return Status::OK();
 }
 
 struct FsFileInfo {
@@ -97,7 +96,7 @@ struct FsFileInfo {
 
 // long and blocking
 template <class CallbackT>
-Status scan_fs(CallbackT &&callback) {
+void scan_fs(CallbackT &&callback) {
   for (int32 i = 0; i < file_type_size; i++) {
     auto file_type = static_cast<FileType>(i);
     if (file_type == FileType::SecureRaw) {
@@ -131,7 +130,6 @@ Status scan_fs(CallbackT &&callback) {
                   })
         .ignore();
   }
-  return Status::OK();
 }
 }  // namespace
 
diff --git a/td/telegram/files/PartsManager.cpp b/td/telegram/files/PartsManager.cpp
index 4a408adeb..95b4e3ee3 100644
--- a/td/telegram/files/PartsManager.cpp
+++ b/td/telegram/files/PartsManager.cpp
@@ -215,8 +215,8 @@ string PartsManager::get_bitmask() {
 }
 
 bool PartsManager::is_part_in_streaming_limit(int part_i) const {
-  auto offset_begin = static_cast<int64>(part_i * get_part_size());
-  auto offset_end = static_cast<int64>(offset_begin + get_part(part_i).size);
+  auto offset_begin = static_cast<int64>(part_i) * static_cast<int64>(get_part_size());
+  auto offset_end = offset_begin + static_cast<int64>(get_part(part_i).size);
 
   if (offset_begin >= get_expected_size()) {
     return false;
diff --git a/td/telegram/net/NetQueryDispatcher.cpp b/td/telegram/net/NetQueryDispatcher.cpp
index 45b4acbf9..7f5172d29 100644
--- a/td/telegram/net/NetQueryDispatcher.cpp
+++ b/td/telegram/net/NetQueryDispatcher.cpp
@@ -252,7 +252,7 @@ void NetQueryDispatcher::update_mtproto_header() {
 }
 
 void NetQueryDispatcher::update_valid_dc(DcId dc_id) {
-  wait_dc_init(dc_id, true);
+  wait_dc_init(dc_id, true).ignore();
 }
 
 bool NetQueryDispatcher::is_dc_inited(int32 raw_dc_id) {