fixed compilation warnings with newer versions of clang (#2047)

include/libtorrent/aux_/typed_span.hpp

@@ -72,7 +72,8 @@ namespace libtorrent { namespace aux {
 		typed_span first(underlying_index n) const
 		{
 			TORRENT_ASSERT(n >= 0);
-			return this->base::first(std::size_t(n));
+			auto s = this->base::first(std::size_t(n));
+			return {s.data(), s.size()};
 		}
 
 		typed_span first(std::size_t n) const
@@ -86,7 +87,8 @@ namespace libtorrent { namespace aux {
 		typed_span last(underlying_index n) const
 		{
 			TORRENT_ASSERT(n >= 0);
-			return this->base::last(std::size_t(n));
+			auto s = this->base::last(std::size_t(n));
+			return {s.data(), s.size()};
 		}
 
 		typed_span last(std::size_t n) const
@@ -100,7 +102,8 @@ namespace libtorrent { namespace aux {
 		typed_span subspan(underlying_index offset) const
 		{
 			TORRENT_ASSERT(offset >= 0);
-			return this->base::subspan(std::size_t(offset));
+			auto s = this->base::subspan(std::size_t(offset));
+			return {s.data(), s.size()};
 		}
 
 		template <typename U = underlying_index, typename Cond
@@ -109,7 +112,8 @@ namespace libtorrent { namespace aux {
 		{
 			TORRENT_ASSERT(offset >= 0);
 			TORRENT_ASSERT(count >= 0);
-			return this->base::subspan(std::size_t(offset), std::size_t(count));
+			auto s = this->base::subspan(std::size_t(offset), std::size_t(count));
+			return {s.data(), s.size()};
 		}
 
 		typed_span subspan(std::size_t offset) const

include/libtorrent/bt_peer_connection.hpp

@@ -107,7 +107,7 @@ namespace libtorrent {
 			share_mode_msg = 8
 		};
 
-		~bt_peer_connection();
+		~bt_peer_connection() override;
 
 #if !defined(TORRENT_DISABLE_ENCRYPTION) && !defined(TORRENT_DISABLE_EXTENSIONS)
 		bool supports_encryption() const
@@ -413,7 +413,18 @@ namespace libtorrent {
 		// true if rc4, false if plaintext
 		bool m_rc4_encrypted:1;
 
+// this is a legitimate use of a shadow field
+#ifdef __clang__
+#pragma clang diagnostic push
+// macOS clang doesn't have -Wshadow-field
+#pragma clang diagnostic ignored "-Wunknown-pragmas"
+#pragma clang diagnostic ignored "-Wshadow-field"
+#endif
 		crypto_receive_buffer m_recv_buffer;
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
 #endif
 
 		std::string m_client_version;

include/libtorrent/http_tracker_connection.hpp

@@ -84,7 +84,6 @@ namespace libtorrent {
 
 		virtual void on_timeout(error_code const&) {}
 
-		tracker_manager& m_man;
 		std::shared_ptr<http_connection> m_tracker_connection;
 		address m_tracker_ip;
 #if TORRENT_USE_I2P

include/libtorrent/peer_connection.hpp

@@ -274,7 +274,7 @@ namespace aux {
 		// do in the constructor).
 		virtual void start();
 
-		virtual ~peer_connection();
+		virtual ~peer_connection() override;
 
 		void set_peer_info(torrent_peer* pi) override
 		{

include/libtorrent/storage.hpp

@@ -380,7 +380,7 @@ namespace libtorrent {
 		explicit default_storage(storage_params const& params, file_pool&);
 
 		// hidden
-		~default_storage();
+		~default_storage() override;
 
 		virtual bool has_any_file(storage_error& ec) override;
 		virtual void set_file_priority(aux::vector<std::uint8_t, file_index_t> const& prio

include/libtorrent/torrent.hpp

@@ -319,7 +319,7 @@ namespace libtorrent {
 		torrent(aux::session_interface& ses, int block_size
 			, bool session_paused, add_torrent_params const& p
 			, sha1_hash const& info_hash);
-		~torrent();
+		~torrent() override;
 
 		// This may be called from multiple threads
 		sha1_hash const& info_hash() const { return m_info_hash; }

include/libtorrent/upnp.hpp

@@ -258,11 +258,6 @@ private:
 		// to 0, the mapping is not in use
 		tcp::endpoint local_ep;
 
-		// the external (on the NAT router) port
-		// for the mapping. This is the port we
-		// should announce to others
-		int external_port = 0;
-
 		// the number of times this mapping has failed
 		int failcount = 0;
 	};

src/disk_io_thread_pool.cpp

@@ -112,7 +112,7 @@ namespace libtorrent {
 			if (!m_abort)
 			{
 				auto new_end = std::remove_if(m_threads.begin(), m_threads.end()
-					, [id, &l](std::thread& t)
+					, [id](std::thread& t)
 				{
 					if (t.get_id() == id)
 					{

src/http_tracker_connection.cpp

@@ -66,7 +66,6 @@ namespace libtorrent {
 		, tracker_request const& req
 		, std::weak_ptr<request_callback> c)
 		: tracker_connection(man, req, ios, c)
-		, m_man(man)
 #if TORRENT_USE_I2P
 		, m_i2p_conn(nullptr)
 #endif