diff --git a/contrib/epee/include/string_tools.h b/contrib/epee/include/string_tools.h
index 307323aa1..5a1ef0743 100644
--- a/contrib/epee/include/string_tools.h
+++ b/contrib/epee/include/string_tools.h
@@ -161,7 +161,7 @@ DISABLE_GCC_WARNING(maybe-uninitialized)
       val = boost::lexical_cast<XType>(str_id);
       return true;
     }
-    catch(std::exception& /*e*/)
+    catch(const std::exception& /*e*/)
     {
       //const char* pmsg = e.what();
       return false;
diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index 07a0e67b1..ee4368e86 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -2894,7 +2894,7 @@ uint64_t BlockchainLMDB::add_block(const block& blk, const size_t& block_size, c
   {
     BlockchainDB::add_block(blk, block_size, cumulative_difficulty, coins_generated, txs);
   }
-  catch (DB_ERROR_TXN_START& e)
+  catch (const DB_ERROR_TXN_START& e)
   {
     throw;
   }
diff --git a/src/daemon/command_parser_executor.cpp b/src/daemon/command_parser_executor.cpp
index 5307b2472..8970f9407 100644
--- a/src/daemon/command_parser_executor.cpp
+++ b/src/daemon/command_parser_executor.cpp
@@ -173,7 +173,7 @@ bool t_command_parser_executor::print_block(const std::vector<std::string>& args
     uint64_t height = boost::lexical_cast<uint64_t>(arg);
     return m_executor.print_block_by_height(height);
   }
-  catch (boost::bad_lexical_cast&)
+  catch (const boost::bad_lexical_cast&)
   {
     crypto::hash block_hash;
     if (parse_hash256(arg, block_hash))
@@ -420,7 +420,7 @@ bool t_command_parser_executor::out_peers(const std::vector<std::string>& args)
 		limit = std::stoi(args[0]);
 	}
 	  
-	catch(std::exception& ex) {
+	catch(const std::exception& ex) {
 		_erro("stoi exception");
 		return false;
 	}
@@ -450,7 +450,7 @@ bool t_command_parser_executor::hard_fork_info(const std::vector<std::string>& a
     try {
       version = std::stoi(args[0]);
     }
-    catch(std::exception& ex) {
+    catch(const std::exception& ex) {
         return false;
     }
     if (version <= 0 || version > 255)
diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index e34e718d2..0a5c9e531 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -5175,7 +5175,7 @@ bool simple_wallet::show_transfers(const std::vector<std::string> &args_)
     try {
       min_height = boost::lexical_cast<uint64_t>(local_args[0]);
     }
-    catch (boost::bad_lexical_cast &) {
+    catch (const boost::bad_lexical_cast &) {
       fail_msg_writer() << tr("bad min_height parameter:") << " " << local_args[0];
       return true;
     }
@@ -5187,7 +5187,7 @@ bool simple_wallet::show_transfers(const std::vector<std::string> &args_)
     try {
       max_height = boost::lexical_cast<uint64_t>(local_args[0]);
     }
-    catch (boost::bad_lexical_cast &) {
+    catch (const boost::bad_lexical_cast &) {
       fail_msg_writer() << tr("bad max_height parameter:") << " " << local_args[0];
       return true;
     }