diff --git a/test/is_copy_constructible_test.cpp b/test/is_copy_constructible_test.cpp
index 0ab0a9f..b8e3c46 100644
--- a/test/is_copy_constructible_test.cpp
+++ b/test/is_copy_constructible_test.cpp
@@ -28,6 +28,7 @@ struct has {
 #endif
 struct has2 {
     const int& i;
+    explicit has2(const int& val) : i(val) {}
 };
 #if (defined _MSC_VER)
 # pragma warning( pop )
@@ -43,7 +44,8 @@ struct has4 { // Copy constructor must be generated by compiler
 };
 
 struct has_not: public boost::noncopyable {
-    has_not() {}
+    typedef boost::noncopyable base_t;
+    has_not() : base_t() {}
 };
 
 #ifndef BOOST_NO_CXX11_DELETED_FUNCTIONS
@@ -61,7 +63,8 @@ struct has_not3 {
 #endif // BOOST_NO_CXX11_DELETED_FUNCTIONS
 
 struct has_not4: private boost::noncopyable {
-    has_not4() {}
+    typedef boost::noncopyable base_t;
+    has_not4() : base_t() {}
 private:
     has_not4(const has_not4&);
 };