+ /*
+ * gcc versions before 5.0 lack some type traits defined in C++11.
+ * Since in this instance we use the trait to prevent misuses
+ * of memmove (and statically assert) and not to generate different
+ * code based on this property, simply set value to true and allow
+ * the code to compile. Anyone using a contemporary compiler will
+ * catch the error.
+ */
+#if __GNUG__ && __GNUC__ < 5
+ static constexpr bool value = true;
+#else