Make static_string trivially copyable

Author: Quuxplusone

include/boost/static_string/static_string.hpp

@@ -1093,11 +1093,7 @@ class basic_static_string
 
       Copy constructor.
   */
-  BOOST_STATIC_STRING_CPP14_CONSTEXPR
-  basic_static_string(const basic_static_string& other) noexcept
-  {
-    assign(other);
-  }
+  basic_static_string(const basic_static_string& other) = default;
 
   /** Constructor.
 
@@ -1185,12 +1181,8 @@ class basic_static_string
 
       @throw std::length_error `s.size() > max_size()`.
   */
-  BOOST_STATIC_STRING_CPP14_CONSTEXPR
   basic_static_string&
-  operator=(const basic_static_string& s)
-  {
-    return assign(s);
-  }
+  operator=(const basic_static_string& s) = default;
 
   /** Assign to the string.
 

test/static_string.cpp

@@ -295,6 +295,53 @@ testTWS(Arithmetic value, const wchar_t* wstr_expected = L"", bool test_expected
   }
 }
 
+// done
+static
+void
+testTypeTraits()
+{
+    {
+        using S = static_string<0>;
+        static_assert(std::is_trivially_copyable<S>::value, "");
+        static_assert(!std::is_trivially_default_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_constructible<S>::value, "");
+        static_assert(std::is_trivially_move_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_assignable<S>::value, "");
+        static_assert(std::is_trivially_move_assignable<S>::value, "");
+        static_assert(std::is_trivially_destructible<S>::value, "");
+    }
+    {
+        using S = static_string<1>;
+        static_assert(std::is_trivially_copyable<S>::value, "");
+        static_assert(!std::is_trivially_default_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_constructible<S>::value, "");
+        static_assert(std::is_trivially_move_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_assignable<S>::value, "");
+        static_assert(std::is_trivially_move_assignable<S>::value, "");
+        static_assert(std::is_trivially_destructible<S>::value, "");
+    }
+    {
+        using S = static_string<20>;
+        static_assert(std::is_trivially_copyable<S>::value, "");
+        static_assert(!std::is_trivially_default_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_constructible<S>::value, "");
+        static_assert(std::is_trivially_move_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_assignable<S>::value, "");
+        static_assert(std::is_trivially_move_assignable<S>::value, "");
+        static_assert(std::is_trivially_destructible<S>::value, "");
+    }
+    {
+        using S = static_string<400>;
+        static_assert(std::is_trivially_copyable<S>::value, "");
+        static_assert(!std::is_trivially_default_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_constructible<S>::value, "");
+        static_assert(std::is_trivially_move_constructible<S>::value, "");
+        static_assert(std::is_trivially_copy_assignable<S>::value, "");
+        static_assert(std::is_trivially_move_assignable<S>::value, "");
+        static_assert(std::is_trivially_destructible<S>::value, "");
+    }
+}
+
 // done
 static
 void
@@ -7461,6 +7508,8 @@ runTests()
   constexpr auto cxper = testConstantEvaluation();
   static_cast<void>(cxper);
 
+  testTypeTraits();
+
   testConstruct();
 
   testAssignment();