diff --git a/types.hpp b/types.hpp
index 2bc84e3f..5bb317b9 100644
--- a/types.hpp
+++ b/types.hpp
@@ -56,58 +56,6 @@ template <typename T>
 std::string type_to_string (void);
 
 
-template <typename T>
-struct sign_types;
-
-
-template <> struct sign_types <int8_t> {
-    typedef  int8_t with_sign;
-    typedef uint8_t without_sign;
-};
-
-
-template <> struct sign_types <uint8_t> {
-    typedef  int8_t with_sign;
-    typedef uint8_t without_sign;
-};
-
-
-template <> struct sign_types <int16_t> {
-    typedef  int16_t with_sign;
-    typedef uint16_t without_sign;
-};
-
-
-template <> struct sign_types <uint16_t> {
-    typedef  int16_t with_sign;
-    typedef uint16_t without_sign;
-};
-
-
-template <> struct sign_types <int32_t> {
-    typedef  int32_t with_sign;
-    typedef uint32_t without_sign;
-};
-
-
-template <> struct sign_types <uint32_t> {
-    typedef  int32_t with_sign;
-    typedef uint32_t without_sign;
-};
-
-
-template <> struct sign_types <int64_t> {
-    typedef   signed long with_sign;
-    typedef unsigned long without_sign;
-};
-
-
-template <> struct sign_types <uint64_t> {
-    typedef   signed long with_sign;
-    typedef unsigned long without_sign;
-};
-
-
 namespace detail {
     template <typename T, typename V>
     T