diff --git a/.travis.yml b/.travis.yml
index 7bf39ee..9665a6a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,8 +9,8 @@ env:
 #  - CXX_STANDARD=c++14
 
 compiler:
-#  - clang
   - gcc
+  - clang
 
 before_install:
   - CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
@@ -29,6 +29,6 @@ before_install:
 script:
   - mkdir build/cmake
   - cd build/cmake
-  - cmake -G "Unix Makefiles" ../..
+  - cmake ../..
   - make
   - ctest
diff --git a/src/libraries/xeumeuleu/bridges/xerces/detail/import.hpp b/src/libraries/xeumeuleu/bridges/xerces/detail/import.hpp
index 225514b..ccf56cf 100644
--- a/src/libraries/xeumeuleu/bridges/xerces/detail/import.hpp
+++ b/src/libraries/xeumeuleu/bridges/xerces/detail/import.hpp
@@ -54,7 +54,7 @@ namespace detail
                                                  XERCES_CPP_NAMESPACE::DOMNode& to )
     {
         xerces_ptr< XERCES_CPP_NAMESPACE::DOMNode > child( document.importNode( const_cast< XERCES_CPP_NAMESPACE::DOMNode* >( &from ), false ) );
-        *to.appendChild( child.get() );
+        to.appendChild( child.get() );
         return child.release();
     }
 }
diff --git a/src/libraries/xeumeuleu/bridges/xerces/detail/locator_handler.hpp b/src/libraries/xeumeuleu/bridges/xerces/detail/locator_handler.hpp
index 56e6fed..ffdd58e 100644
--- a/src/libraries/xeumeuleu/bridges/xerces/detail/locator_handler.hpp
+++ b/src/libraries/xeumeuleu/bridges/xerces/detail/locator_handler.hpp
@@ -76,10 +76,14 @@ class locator_handler : public XERCES_CPP_NAMESPACE::DOMUserDataHandler
             break;
         case NODE_CLONED:
         case NODE_IMPORTED:
+        {
             const locator* l = static_cast< locator* >( src->getUserData( key ) );
             delete static_cast< locator* >( dst->getUserData( key ) );
             dst->setUserData( key, l ? new locator( *l ) : 0, this );
             break;
+        }
+        default:
+            break;
         }
     }
     //@}
diff --git a/src/libraries/xeumeuleu/streams/id.hpp b/src/libraries/xeumeuleu/streams/id.hpp
index 6fa4e24..30db8c6 100644
--- a/src/libraries/xeumeuleu/streams/id.hpp
+++ b/src/libraries/xeumeuleu/streams/id.hpp
@@ -45,7 +45,7 @@ namespace xml
 */
 // Created: MAT 2014-12-04
 // =============================================================================
-    class id
+class id
 {
 public:
     //! @name Constructors/Destructor
diff --git a/src/libraries/xeumeuleu/streams/xistringstream.hpp b/src/libraries/xeumeuleu/streams/xistringstream.hpp
index 54e7254..2c171b1 100644
--- a/src/libraries/xeumeuleu/streams/xistringstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xistringstream.hpp
@@ -60,12 +60,22 @@ class xistringstream : private document, public xistream
 public:
     //! @name Constructors/Destructor
     //@{
-    xistringstream( const std::string& data, const grammar& grammar = null_grammar(), const id& id = id() )
+    explicit xistringstream( const std::string& data, const grammar& grammar = null_grammar() )
+        : document( data.c_str(), data.size(), 0, grammar, id() )
+        , xistream( input_ )
+        , input_( *document_ )
+    {}
+    xistringstream( const std::string& data, const grammar& grammar, const id& id )
         : document( data.c_str(), data.size(), 0, grammar, id )
         , xistream( input_ )
         , input_( *document_ )
     {}
-    xistringstream( const std::string& data, const encoding& encoding, const grammar& grammar = null_grammar(), const id& id = id() )
+    xistringstream( const std::string& data, const encoding& encoding, const grammar& grammar = null_grammar() )
+        : document( data.c_str(), data.size(), &encoding, grammar, id() )
+        , xistream( input_ )
+        , input_( *document_ )
+    {}
+    xistringstream( const std::string& data, const encoding& encoding, const grammar& grammar, const id& id )
         : document( data.c_str(), data.size(), &encoding, grammar, id )
         , xistream( input_ )
         , input_( *document_ )
diff --git a/src/libraries/xeumeuleu/streams/xisubstream.hpp b/src/libraries/xeumeuleu/streams/xisubstream.hpp
index b470d27..a2b7173 100644
--- a/src/libraries/xeumeuleu/streams/xisubstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xisubstream.hpp
@@ -76,14 +76,6 @@ class xisubstream : private xi_base_member, public xistream
     virtual ~xisubstream()
     {}
     //@}
-
-    //! @name Operators
-    //@{
-    operator xistream&() const
-    {
-        return const_cast< xisubstream& >( *this );
-    }
-    //@}
 };
 
 }
diff --git a/src/libraries/xeumeuleu/streams/xofstream.hpp b/src/libraries/xeumeuleu/streams/xofstream.hpp
index 06aeb02..d4f244c 100644
--- a/src/libraries/xeumeuleu/streams/xofstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xofstream.hpp
@@ -61,7 +61,14 @@ class xofstream : private document, private flushable, public xostream
 public:
     //! @name Constructors/Destructor
     //@{
-    explicit xofstream( const std::string& filename, const encoding& encoding = encoding() )
+    explicit xofstream( const std::string& filename )
+        : xostream( output_ )
+        , output_  ( *document_, *document_, *this )
+        , filename_( filename )
+        , encoding_( encoding() )
+        , flushed_ ( false )
+    {}
+    xofstream( const std::string& filename, const encoding& encoding )
         : xostream( output_ )
         , output_  ( *document_, *document_, *this )
         , filename_( filename )
diff --git a/src/libraries/xeumeuleu/streams/xostreamstream.hpp b/src/libraries/xeumeuleu/streams/xostreamstream.hpp
index 4afeb71..5315f8b 100644
--- a/src/libraries/xeumeuleu/streams/xostreamstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xostreamstream.hpp
@@ -58,7 +58,14 @@ class xostreamstream : private document, private flushable, public xostream
 public:
     //! @name Constructors/Destructor
     //@{
-    explicit xostreamstream( std::basic_ostream< char >& stream, const encoding& encoding = encoding() )
+    explicit xostreamstream( std::basic_ostream< char >& stream )
+        : xostream( output_ )
+        , output_  ( *document_, *document_, *this )
+        , stream_  ( stream )
+        , encoding_( encoding() )
+        , flushed_ ( false )
+    {}
+    xostreamstream( std::basic_ostream< char >& stream, const encoding& encoding )
         : xostream( output_ )
         , output_  ( *document_, *document_, *this )
         , stream_  ( stream )
diff --git a/src/libraries/xeumeuleu/streams/xostringstream.hpp b/src/libraries/xeumeuleu/streams/xostringstream.hpp
index fdcbae4..2afa5d7 100644
--- a/src/libraries/xeumeuleu/streams/xostringstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xostringstream.hpp
@@ -58,7 +58,12 @@ class xostringstream : private document, public xostream
 public:
     //! @name Constructors/Destructor
     //@{
-    explicit xostringstream( const encoding& encoding = encoding() )
+    xostringstream()
+        : xostream( output_ )
+        , output_  ( *document_, *document_ )
+        , encoding_( encoding() )
+    {}
+    explicit xostringstream( const encoding& encoding )
         : xostream( output_ )
         , output_  ( *document_, *document_ )
         , encoding_( encoding )
diff --git a/src/libraries/xeumeuleu/streams/xosubstream.hpp b/src/libraries/xeumeuleu/streams/xosubstream.hpp
index be55b3e..b9c3d1f 100644
--- a/src/libraries/xeumeuleu/streams/xosubstream.hpp
+++ b/src/libraries/xeumeuleu/streams/xosubstream.hpp
@@ -75,14 +75,6 @@ class xosubstream : private xo_base_member, public xostream
     {}
     //@}
 
-    //! @name Operators
-    //@{
-    operator xostream&() const
-    {
-        return const_cast< xosubstream& >( *this );
-    }
-    //@}
-
 private:
     //! @name Operations
     //@{
diff --git a/src/tests/xeumeuleu_test/attribute_test.cpp b/src/tests/xeumeuleu_test/attribute_test.cpp
index 35cd388..ced71a5 100644
--- a/src/tests/xeumeuleu_test/attribute_test.cpp
+++ b/src/tests/xeumeuleu_test/attribute_test.cpp
@@ -324,7 +324,7 @@ BOOST_AUTO_TEST_CASE( writing_attribute_pointer_equal_to_nullptr_fallback_value_
 BOOST_AUTO_TEST_CASE( writing_attribute_pointer_different_from_nullptr_fallback_value_writes_it )
 {
     xml::xostringstream xos;
-    const user_type t;
+    const user_type t = user_type();
     xos << xml::start( "root" )
             << xml::attribute( "attribute", &t, nullptr );
     const std::string expected = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?>\n"