diff --git a/include/libtorrent/add_torrent_params.hpp b/include/libtorrent/add_torrent_params.hpp
index 04699f495..6e1d7246d 100644
--- a/include/libtorrent/add_torrent_params.hpp
+++ b/include/libtorrent/add_torrent_params.hpp
@@ -301,6 +301,7 @@ namespace libtorrent
 		// a list of hostname and port pairs, representing DHT nodes to be added
 		// to the session (if DHT is enabled). The hostname may be an IP address.
 		std::vector<std::pair<std::string, int>> dht_nodes;
+
 		std::string name;
 
 		// the path where the torrent is or will be stored.
diff --git a/include/libtorrent/aux_/openssl.hpp b/include/libtorrent/aux_/openssl.hpp
index 6280d3c11..563dee23a 100644
--- a/include/libtorrent/aux_/openssl.hpp
+++ b/include/libtorrent/aux_/openssl.hpp
@@ -57,7 +57,6 @@ inline void openssl_set_tlsext_hostname(SSL* s, char const* name)
 #endif
 }
 
-#if BOOST_VERSION >= 104700
 #if OPENSSL_VERSION_NUMBER >= 0x90812f
 
 inline void openssl_set_tlsext_servername_callback(SSL_CTX* ctx
@@ -82,7 +81,6 @@ inline GENERAL_NAME* openssl_general_name_value(GENERAL_NAMES* gens, int i)
 }
 
 #endif // OPENSSL_VERSION_NUMBER
-#endif // BOOST_VERSION
 
 }
 }
@@ -92,4 +90,3 @@ inline GENERAL_NAME* openssl_general_name_value(GENERAL_NAMES* gens, int i)
 #endif // TORRENT_USE_OPENSSL
 
 #endif // TORRENT_OPENSSL_HPP_INCLUDED
-
diff --git a/include/libtorrent/broadcast_socket.hpp b/include/libtorrent/broadcast_socket.hpp
index 1b4d1e098..81c0517b2 100644
--- a/include/libtorrent/broadcast_socket.hpp
+++ b/include/libtorrent/broadcast_socket.hpp
@@ -40,13 +40,11 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/error_code.hpp"
 
 #include "libtorrent/aux_/disable_warnings_push.hpp"
-
 #include <boost/shared_ptr.hpp>
-#include <boost/function/function3.hpp>
-#include <list>
-
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
+#include <list>
+
 namespace libtorrent
 {
 
diff --git a/include/libtorrent/chained_buffer.hpp b/include/libtorrent/chained_buffer.hpp
index 55bf47d40..39147f441 100644
--- a/include/libtorrent/chained_buffer.hpp
+++ b/include/libtorrent/chained_buffer.hpp
@@ -38,14 +38,11 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/debug.hpp"
 #include "libtorrent/buffer.hpp"
 
-#include "libtorrent/aux_/disable_warnings_push.hpp"
-
-#include <boost/version.hpp>
-#include <boost/asio/buffer.hpp>
 #include <deque>
 #include <vector>
-#include <string.h> // for memcpy
 
+#include "libtorrent/aux_/disable_warnings_push.hpp"
+#include <boost/asio/buffer.hpp>
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
 namespace libtorrent
diff --git a/include/libtorrent/hex.hpp b/include/libtorrent/hex.hpp
index f97dfbbc3..0377b895b 100644
--- a/include/libtorrent/hex.hpp
+++ b/include/libtorrent/hex.hpp
@@ -38,7 +38,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/span.hpp"
 
 #include <string>
-#include <array>
 
 namespace libtorrent
 {
@@ -80,4 +79,3 @@ namespace libtorrent
 }
 
 #endif // TORRENT_HEX_HPP_INCLUDED
-
diff --git a/include/libtorrent/http_seed_connection.hpp b/include/libtorrent/http_seed_connection.hpp
index 63b180024..c574fa1b4 100644
--- a/include/libtorrent/http_seed_connection.hpp
+++ b/include/libtorrent/http_seed_connection.hpp
@@ -51,11 +51,6 @@ namespace libtorrent
 	class torrent;
 	struct peer_request;
 
-	namespace detail
-	{
-		struct session_impl;
-	}
-
 	class TORRENT_EXTRA_EXPORT http_seed_connection
 		: public web_connection_base
 	{
diff --git a/include/libtorrent/kademlia/find_data.hpp b/include/libtorrent/kademlia/find_data.hpp
index 6762adc88..e095bda3b 100644
--- a/include/libtorrent/kademlia/find_data.hpp
+++ b/include/libtorrent/kademlia/find_data.hpp
@@ -40,15 +40,11 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/kademlia/observer.hpp>
 #include <libtorrent/kademlia/msg.hpp>
 
-#include "libtorrent/aux_/disable_warnings_push.hpp"
-
 #include <vector>
 #include <map>
 
-#include <boost/optional.hpp>
-#include <boost/function/function1.hpp>
-#include <boost/function/function2.hpp>
-
+#include "libtorrent/aux_/disable_warnings_push.hpp"
+#include <boost/intrusive_ptr.hpp>
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
 namespace libtorrent { namespace dht
@@ -101,4 +97,3 @@ struct find_data_observer : traversal_observer
 } } // namespace libtorrent::dht
 
 #endif // FIND_DATA_050323_HPP
-
diff --git a/include/libtorrent/kademlia/item.hpp b/include/libtorrent/kademlia/item.hpp
index 0b3ae7cb4..51da64e90 100644
--- a/include/libtorrent/kademlia/item.hpp
+++ b/include/libtorrent/kademlia/item.hpp
@@ -39,10 +39,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/span.hpp>
 #include <libtorrent/kademlia/types.hpp>
 
-#include <vector>
-#include <exception>
-#include <array>
-
 namespace libtorrent { namespace dht
 {
 
diff --git a/include/libtorrent/kademlia/observer.hpp b/include/libtorrent/kademlia/observer.hpp
index 875128976..4e2026101 100644
--- a/include/libtorrent/kademlia/observer.hpp
+++ b/include/libtorrent/kademlia/observer.hpp
@@ -39,10 +39,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/address.hpp>
 
 #include "libtorrent/aux_/disable_warnings_push.hpp"
-
-#include <boost/pool/pool.hpp>
 #include <boost/intrusive_ptr.hpp>
-
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
 namespace libtorrent {
@@ -177,4 +174,3 @@ typedef boost::intrusive_ptr<observer> observer_ptr;
 } }
 
 #endif
-
diff --git a/include/libtorrent/kademlia/routing_table.hpp b/include/libtorrent/kademlia/routing_table.hpp
index 62caf3f90..5df4137a0 100644
--- a/include/libtorrent/kademlia/routing_table.hpp
+++ b/include/libtorrent/kademlia/routing_table.hpp
@@ -40,10 +40,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <tuple>
 #include <array>
 
-#include "libtorrent/aux_/disable_warnings_push.hpp"
-//#include <boost/utility.hpp>
-#include "libtorrent/aux_/disable_warnings_pop.hpp"
-
 #include <libtorrent/kademlia/node_id.hpp>
 #include <libtorrent/kademlia/node_entry.hpp>
 #include <libtorrent/session_settings.hpp>
@@ -336,4 +332,3 @@ private:
 } } // namespace libtorrent::dht
 
 #endif // ROUTING_TABLE_HPP
-
diff --git a/include/libtorrent/kademlia/traversal_algorithm.hpp b/include/libtorrent/kademlia/traversal_algorithm.hpp
index ccbb34494..73734c37a 100644
--- a/include/libtorrent/kademlia/traversal_algorithm.hpp
+++ b/include/libtorrent/kademlia/traversal_algorithm.hpp
@@ -42,12 +42,8 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/address.hpp>
 
 #include "libtorrent/aux_/disable_warnings_push.hpp"
-
 #include <boost/noncopyable.hpp>
 #include <boost/intrusive_ptr.hpp>
-#include <functional>
-#include <boost/pool/pool.hpp>
-
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
 namespace libtorrent { struct dht_lookup; }
diff --git a/include/libtorrent/piece_picker.hpp b/include/libtorrent/piece_picker.hpp
index 0cc4f3e41..513356c41 100644
--- a/include/libtorrent/piece_picker.hpp
+++ b/include/libtorrent/piece_picker.hpp
@@ -39,7 +39,6 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #include <algorithm>
 #include <vector>
-#include <bitset>
 #include <utility>
 #include <cstdint>
 #include <tuple>
diff --git a/include/libtorrent/read_resume_data.hpp b/include/libtorrent/read_resume_data.hpp
index da9010aa4..cd1958f6e 100644
--- a/include/libtorrent/read_resume_data.hpp
+++ b/include/libtorrent/read_resume_data.hpp
@@ -56,4 +56,3 @@ namespace libtorrent
 }
 
 #endif
-
diff --git a/include/libtorrent/session_stats.hpp b/include/libtorrent/session_stats.hpp
index e3921edf4..c2e8a91a8 100644
--- a/include/libtorrent/session_stats.hpp
+++ b/include/libtorrent/session_stats.hpp
@@ -65,4 +65,3 @@ namespace libtorrent
 }
 
 #endif
-
diff --git a/include/libtorrent/socket_type.hpp b/include/libtorrent/socket_type.hpp
index 5a97a1db8..5657650c0 100644
--- a/include/libtorrent/socket_type.hpp
+++ b/include/libtorrent/socket_type.hpp
@@ -44,12 +44,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/io_service.hpp"
 #include "libtorrent/assert.hpp"
 
-#include "libtorrent/aux_/disable_warnings_push.hpp"
-
-#include <boost/type_traits/aligned_storage.hpp>
-
-#include "libtorrent/aux_/disable_warnings_pop.hpp"
-
 #ifdef TORRENT_USE_OPENSSL
 #include "libtorrent/ssl_stream.hpp"
 #endif
diff --git a/include/libtorrent/torrent.hpp b/include/libtorrent/torrent.hpp
index 9c1e15b10..c627da0f1 100644
--- a/include/libtorrent/torrent.hpp
+++ b/include/libtorrent/torrent.hpp
@@ -45,7 +45,6 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #include <boost/enable_shared_from_this.hpp>
 #include <boost/shared_ptr.hpp>
-#include <boost/version.hpp>
 
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
 
@@ -99,12 +98,6 @@ namespace libtorrent
 	class bt_peer_connection;
 	struct listen_socket_t;
 
-
-	namespace aux
-	{
-		struct piece_checker_data;
-	}
-
 	struct time_critical_piece
 	{
 		// when this piece was first requested
@@ -1189,9 +1182,7 @@ namespace libtorrent
 #ifdef TORRENT_USE_OPENSSL
 		boost::shared_ptr<boost::asio::ssl::context> m_ssl_ctx;
 
-#if BOOST_VERSION >= 104700
 		bool verify_peer_cert(bool preverified, boost::asio::ssl::verify_context& ctx);
-#endif
 
 		void init_ssl(std::string const& cert);
 #endif
diff --git a/include/libtorrent/torrent_info.hpp b/include/libtorrent/torrent_info.hpp
index ee272cc29..a4c94fb8a 100644
--- a/include/libtorrent/torrent_info.hpp
+++ b/include/libtorrent/torrent_info.hpp
@@ -414,7 +414,7 @@ namespace libtorrent
 		// for the piece. Note that the string is not 0-terminated.
 		int piece_size(int index) const { return m_files.piece_size(index); }
 		sha1_hash hash_for_piece(int index) const;
-		char const* hash_for_piece_ptr(int index) const
+		char const* hash_for_piece_ptr(int const index) const
 		{
 			TORRENT_ASSERT(index >= 0);
 			TORRENT_ASSERT(index < m_files.num_pieces());
@@ -430,7 +430,7 @@ namespace libtorrent
 				TORRENT_ASSERT(m_piece_hashes >= m_info_section.get());
 				TORRENT_ASSERT(m_piece_hashes < m_info_section.get() + m_info_section_size);
 				TORRENT_ASSERT(index < int(m_info_section_size / 20));
-				return &m_piece_hashes[index*20];
+				return &m_piece_hashes[index * 20];
 			}
 		}
 
diff --git a/include/libtorrent/torrent_status.hpp b/include/libtorrent/torrent_status.hpp
index 2e8b43223..d490a29d0 100644
--- a/include/libtorrent/torrent_status.hpp
+++ b/include/libtorrent/torrent_status.hpp
@@ -336,7 +336,7 @@ namespace libtorrent
 		// piece(s). Divide this number by 1000 to get the fraction.
 		// 
 		// For example, if ``distributed_full_copies`` is 2 and
-		// ``distrbuted_fraction`` is 500, it means that the rarest pieces have
+		// ``distributed_fraction`` is 500, it means that the rarest pieces have
 		// only 2 copies among the peers this torrent is connected to, and that
 		// 50% of all the pieces have more than two copies.
 		// 
diff --git a/src/broadcast_socket.cpp b/src/broadcast_socket.cpp
index 0dc5d63bd..196cb89c7 100644
--- a/src/broadcast_socket.cpp
+++ b/src/broadcast_socket.cpp
@@ -30,8 +30,6 @@ POSSIBILITY OF SUCH DAMAGE.
 
 */
 
-#include <boost/version.hpp>
-
 #include "libtorrent/config.hpp"
 
 #include "libtorrent/aux_/disable_warnings_push.hpp"
@@ -40,16 +38,13 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <pthread.h>
 #endif
 
-#include <boost/asio/ip/host_name.hpp>
 #include <boost/asio/ip/multicast.hpp>
 
-#include "libtorrent/aux_/disable_warnings_pop.hpp"
-
 #ifdef TORRENT_WINDOWS
 #include <iphlpapi.h> // for if_nametoindex
 #endif
 
-#include <functional>
+#include "libtorrent/aux_/disable_warnings_pop.hpp"
 
 #include "libtorrent/socket.hpp"
 #include "libtorrent/enum_net.hpp"
diff --git a/src/chained_buffer.cpp b/src/chained_buffer.cpp
index 398ee1f16..de1f2b945 100644
--- a/src/chained_buffer.cpp
+++ b/src/chained_buffer.cpp
@@ -33,6 +33,8 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/chained_buffer.hpp"
 #include "libtorrent/assert.hpp"
 
+#include <cstring> // for memcpy
+
 namespace libtorrent
 {
 	void chained_buffer::pop_front(int bytes_to_pop)
@@ -123,7 +125,7 @@ namespace libtorrent
 		TORRENT_ASSERT(is_single_thread());
 		char* insert = allocate_appendix(s);
 		if (insert == nullptr) return nullptr;
-		memcpy(insert, buf, s);
+		std::memcpy(insert, buf, s);
 		return insert;
 	}
 
diff --git a/src/kademlia/find_data.cpp b/src/kademlia/find_data.cpp
index 652e127a5..2da5969dd 100644
--- a/src/kademlia/find_data.cpp
+++ b/src/kademlia/find_data.cpp
@@ -41,8 +41,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/hex.hpp> // to_hex
 #endif
 
-#include <vector>
-
 namespace libtorrent { namespace dht
 {
 
@@ -178,4 +176,3 @@ void find_data::done()
 }
 
 } } // namespace libtorrent::dht
-
diff --git a/src/kademlia/item.cpp b/src/kademlia/item.cpp
index aeddc4cf7..6e749a1e2 100644
--- a/src/kademlia/item.cpp
+++ b/src/kademlia/item.cpp
@@ -222,4 +222,3 @@ void item::assign(entry v, span<char const> salt
 }
 
 } } // namespace libtorrent::dht
-
diff --git a/src/read_resume_data.cpp b/src/read_resume_data.cpp
index fb1791c8f..c0d28681e 100644
--- a/src/read_resume_data.cpp
+++ b/src/read_resume_data.cpp
@@ -32,14 +32,9 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #include <cstdint>
 
-#include "libtorrent/aux_/disable_warnings_push.hpp"
-#include <boost/make_shared.hpp>
-#include "libtorrent/aux_/disable_warnings_pop.hpp"
-
 #include "libtorrent/bdecode.hpp"
 #include "libtorrent/read_resume_data.hpp"
 #include "libtorrent/add_torrent_params.hpp"
-#include "libtorrent/announce_entry.hpp"
 #include "libtorrent/socket_io.hpp" // for read_*_endpoint()
 #include "libtorrent/hasher.hpp"
 #include "libtorrent/torrent_info.hpp"
@@ -340,4 +335,3 @@ namespace libtorrent
 		return read_resume_data(rd, ec);
 	}
 }
-
diff --git a/src/session_impl.cpp b/src/session_impl.cpp
index 1ac0ac001..9ff26eb2f 100644
--- a/src/session_impl.cpp
+++ b/src/session_impl.cpp
@@ -257,7 +257,7 @@ namespace aux {
 #endif
 	}
 
-#if defined TORRENT_USE_OPENSSL && BOOST_VERSION >= 104700 && OPENSSL_VERSION_NUMBER >= 0x90812f
+#if defined TORRENT_USE_OPENSSL && OPENSSL_VERSION_NUMBER >= 0x90812f
 	namespace {
 	// when running bittorrent over SSL, the SNI (server name indication)
 	// extension is used to know which torrent the incoming connection is
@@ -415,13 +415,11 @@ namespace aux {
 		error_code ec;
 #ifdef TORRENT_USE_OPENSSL
 		m_ssl_ctx.set_verify_mode(boost::asio::ssl::context::verify_none, ec);
-#if BOOST_VERSION >= 104700
 #if OPENSSL_VERSION_NUMBER >= 0x90812f
 		aux::openssl_set_tlsext_servername_callback(m_ssl_ctx.native_handle()
 			, servername_callback);
 		aux::openssl_set_tlsext_servername_arg(m_ssl_ctx.native_handle(), this);
 #endif // OPENSSL_VERSION_NUMBER
-#endif // BOOST_VERSION
 #endif
 
 #ifndef TORRENT_DISABLE_DHT
diff --git a/src/session_stats.cpp b/src/session_stats.cpp
index fef2d48b9..43f68d14b 100644
--- a/src/session_stats.cpp
+++ b/src/session_stats.cpp
@@ -176,7 +176,7 @@ namespace libtorrent
 		METRIC(net, recv_tracker_bytes)
 
 		// the number of sockets currently waiting for upload and download
-		// bandwidht from the rate limiter.
+		// bandwidth from the rate limiter.
 		METRIC(net, limiter_up_queue)
 		METRIC(net, limiter_down_queue)
 
diff --git a/src/torrent.cpp b/src/torrent.cpp
index eec2a79db..ac312053c 100644
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -54,10 +54,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #ifdef TORRENT_USE_OPENSSL
 #include "libtorrent/ssl_stream.hpp"
 #include <boost/asio/ssl/context.hpp>
-#include <openssl/rand.h>
-#if BOOST_VERSION >= 104700
 #include <boost/asio/ssl/verify_context.hpp>
-#endif // BOOST_VERSION
 #endif // TORRENT_USE_OPENSSL
 
 #include "libtorrent/aux_/disable_warnings_pop.hpp"
@@ -1481,7 +1478,6 @@ namespace libtorrent
 
 #ifdef TORRENT_USE_OPENSSL
 
-#if BOOST_VERSION >= 104700
 	bool torrent::verify_peer_cert(bool preverified, boost::asio::ssl::verify_context& ctx)
 	{
 		// if the cert wasn't signed by the correct CA, fail the verification
@@ -1573,7 +1569,6 @@ namespace libtorrent
 		return false;
 #endif
 	}
-#endif // BOOST_VERSION
 
 	void torrent::init_ssl(std::string const& cert)
 	{
@@ -1590,7 +1585,6 @@ namespace libtorrent
 
 		TORRENT_ASSERT(RAND_status() == 1);
 
-#if BOOST_VERSION >= 104700
 		// create the SSL context for this torrent. We need to
 		// inject the root certificate, and no other, to
 		// verify other peers against
@@ -1683,10 +1677,6 @@ namespace libtorrent
 		m_ssl_ctx = ctx;
 		// tell the client we need a cert for this torrent
 		alerts().emplace_alert<torrent_need_cert_alert>(get_handle());
-#else
-		set_error(boost::asio::error::operation_not_supported, torrent_status::error_file_ssl_ctx);
-		pause();
-#endif
 	}
 
 #endif // TORRENT_OPENSSL
@@ -5694,11 +5684,6 @@ namespace libtorrent
 	{
 		if (!m_ssl_ctx) return;
 
-#if BOOST_VERSION < 105400
-		if (alerts().should_post<torrent_error_alert>())
-			alerts().emplace_alert<torrent_error_alert>(get_handle()
-				, error_code(boost::system::errc::not_supported, generic_category()), "[certificate]");
-#else
 		boost::asio::const_buffer certificate_buf(certificate.c_str(), certificate.size());
 
 		using boost::asio::ssl::context;
@@ -5725,7 +5710,6 @@ namespace libtorrent
 			if (alerts().should_post<torrent_error_alert>())
 				alerts().emplace_alert<torrent_error_alert>(get_handle(), ec, "[dh params]");
 		}
-#endif // BOOST_VERSION
 	}
 
 #endif
@@ -6905,14 +6889,14 @@ namespace libtorrent
 			(void)ret;
 			TORRENT_ASSERT(ret);
 
-#if defined TORRENT_USE_OPENSSL && BOOST_VERSION >= 104700
+#if defined TORRENT_USE_OPENSSL
 			if (is_ssl_torrent())
 			{
 				// for ssl sockets, set the hostname
 				std::string host_name = aux::to_hex(m_torrent_file->info_hash());
 
-#define CASE(t) case socket_type_int_impl<ssl_stream<t> >::value: \
-	s->get<ssl_stream<t> >()->set_host_name(host_name); break;
+#define CASE(t) case socket_type_int_impl<ssl_stream<t>>::value: \
+	s->get<ssl_stream<t>>()->set_host_name(host_name); break;
 
 				switch (s->type())
 				{
@@ -7096,15 +7080,14 @@ namespace libtorrent
 //		INVARIANT_CHECK;
 
 #ifdef TORRENT_USE_OPENSSL
-#if BOOST_VERSION >= 104700
 		if (is_ssl_torrent())
 		{
 			// if this is an SSL torrent, don't allow non SSL peers on it
 			boost::shared_ptr<socket_type> s = p->get_socket();
 
 			//
-#define SSL(t) socket_type_int_impl<ssl_stream<t> >::value: \
-			ssl_conn = s->get<ssl_stream<t> >()->native_handle(); \
+#define SSL(t) socket_type_int_impl<ssl_stream<t>>::value: \
+			ssl_conn = s->get<ssl_stream<t>>()->native_handle(); \
 			break;
 
 			SSL* ssl_conn = nullptr;
@@ -7144,13 +7127,6 @@ namespace libtorrent
 				return false;
 			}
 		}
-#else // BOOST_VERSION
-		if (is_ssl_torrent())
-		{
-			p->disconnect(boost::asio::error::operation_not_supported, op_bittorrent);
-			return false;
-		}
-#endif
 #else // TORRENT_USE_OPENSSL
 		if (is_ssl_torrent())
 		{
diff --git a/src/torrent_info.cpp b/src/torrent_info.cpp
index 06f56828c..1ac04f822 100644
--- a/src/torrent_info.cpp
+++ b/src/torrent_info.cpp
@@ -1075,7 +1075,7 @@ namespace libtorrent
 	}
 
 	bool torrent_info::parse_info_section(bdecode_node const& info
-		, error_code& ec, int flags)
+		, error_code& ec, int const flags)
 	{
 		TORRENT_UNUSED(flags);
 		if (info.type() != bdecode_node::dict_t)
@@ -1129,7 +1129,7 @@ namespace libtorrent
 		if (name.empty()) name = aux::to_hex(m_info_hash);
 
 		// extract file list
-		bdecode_node files_node = info.dict_find_list("files");
+		bdecode_node const files_node = info.dict_find_list("files");
 		if (!files_node)
 		{
 			// if there's no list of files, there has to be a length
@@ -1264,13 +1264,12 @@ namespace libtorrent
 
 
 	bool torrent_info::add_merkle_nodes(std::map<int, sha1_hash> const& subtree
-		, int piece)
+		, int const piece)
 	{
 		INVARIANT_CHECK;
 
 		int n = m_merkle_first_leaf + piece;
-		typedef std::map<int, sha1_hash>::const_iterator iter;
-		iter it = subtree.find(n);
+		auto const it = subtree.find(n);
 		if (it == subtree.end()) return false;
 		sha1_hash h = it->second;
 
@@ -1282,7 +1281,7 @@ namespace libtorrent
 		{
 			int const sibling = merkle_get_sibling(n);
 			int const parent = merkle_get_parent(n);
-			iter const sibling_hash = subtree.find(sibling);
+			auto const sibling_hash = subtree.find(sibling);
 			if (sibling_hash == subtree.end())
 				return false;
 			to_add[n] = h;
@@ -1306,17 +1305,16 @@ namespace libtorrent
 		// the nodes and piece hash matched the root-hash
 		// insert them into our tree
 
-		for (std::map<int, sha1_hash>::iterator i = to_add.begin()
-			, end(to_add.end()); i != end; ++i)
+		for (auto const& i : to_add)
 		{
-			m_merkle_tree[i->first] = i->second;
+			m_merkle_tree[i.first] = i.second;
 		}
 		return true;
 	}
 
 	// builds a list of nodes that are required to verify
 	// the given piece
-	std::map<int, sha1_hash> torrent_info::build_merkle_list(int piece) const
+	std::map<int, sha1_hash> torrent_info::build_merkle_list(int const piece) const
 	{
 		INVARIANT_CHECK;
 
@@ -1338,7 +1336,7 @@ namespace libtorrent
 	}
 
 	bool torrent_info::parse_torrent_file(bdecode_node const& torrent_file
-		, error_code& ec, int flags)
+		, error_code& ec, int const flags)
 	{
 		if (torrent_file.type() != bdecode_node::dict_t)
 		{