diff --git a/src/face.cpp b/src/face.cpp
index 3e5a4b1..5e9cd3c 100644
--- a/src/face.cpp
+++ b/src/face.cpp
@@ -77,11 +77,11 @@
     {
       protocol = m_config.getParsedConfiguration().get<std::string>("protocol");
     }
-  catch (const boost::property_tree::ptree_bad_path& error)
+  catch (boost::property_tree::ptree_bad_path& error)
     {
       // protocol not specified
     }
-  catch (const boost::property_tree::ptree_bad_data& error)
+  catch (boost::property_tree::ptree_bad_data& error)
     {
       throw ConfigFile::Error(error.what());
     }
@@ -276,7 +276,7 @@
       // break
       m_ioService->reset();
     }
-  catch (const std::exception&)
+  catch (std::exception&)
     {
       m_ioService->reset();
       m_pendingInterestTable.clear();