diff --git a/include/boost/regex/v4/basic_regex.hpp b/include/boost/regex/v4/basic_regex.hpp
index 4a396a0e..14d19218 100644
--- a/include/boost/regex/v4/basic_regex.hpp
+++ b/include/boost/regex/v4/basic_regex.hpp
@@ -69,6 +69,10 @@ class named_subexpressions_base
 {
 public:
    virtual int get_id(const charT* i, const charT* j) = 0;
+#ifdef __GNUC__
+   // warning supression:
+   virtual ~named_subexpressions_base(){}
+#endif
 };
 
 template <class charT>
diff --git a/include/boost/regex/v4/regex_traits_defaults.hpp b/include/boost/regex/v4/regex_traits_defaults.hpp
index 55529c5e..5b2c6bc3 100644
--- a/include/boost/regex/v4/regex_traits_defaults.hpp
+++ b/include/boost/regex/v4/regex_traits_defaults.hpp
@@ -339,6 +339,21 @@ inline const charT* get_escape_R_string()
 #endif
 }
 
+template <>
+inline const char* get_escape_R_string<char>()
+{
+#ifdef BOOST_MSVC
+#  pragma warning(push)
+#  pragma warning(disable:4309)
+#endif
+   static const char e2[] = { '(', '?', '>', '\x0D', '\x0A', '?', 
+      '|', '[', '\x0A', '\x0B', '\x0C', '\x85', ']', ')', '\0' };
+   return e2;
+#ifdef BOOST_MSVC
+#  pragma warning(pop)
+#endif
+}
+
 } // re_detail
 } // boost