diff --git a/fit/alias.h b/fit/alias.h
index 3299525..d7b8d90 100644
--- a/fit/alias.h
+++ b/fit/alias.h
@@ -50,6 +50,10 @@
 ///     constexpr auto alias_value(Alias&&);
 /// 
 
+#ifdef _MSC_VER
+#pragma warning(disable: 4579)
+#endif
+
 namespace fit {
 
 template<class T>
@@ -134,6 +138,15 @@ namespace detail {
 template<class T, class Tag>
 struct alias_static_storage
 {
+#ifdef _MSC_VER
+    // Since we disable the error for 4579 on MSVC, which leaves the static
+    // member unitialized at runtime, it is, therefore, only safe to use this
+    // class on types that are empty with constructors that have no possible
+    // side effects.
+    static_assert(std::is_empty<T>::value && 
+        std::is_literal_type<T>::value && 
+        std::is_default_constructible<T>::value, "In-class initialization is not yet implemented on MSVC");
+#endif
     static constexpr T value = T();
 };
 
diff --git a/fit/by.h b/fit/by.h
index 5846310..9d45ed4 100644
--- a/fit/by.h
+++ b/fit/by.h
@@ -170,6 +170,8 @@ struct by_adaptor : Projection, F
         return always_ref(*this)(xs...);
     }
 
+    FIT_INHERIT_DEFAULT(by_adaptor, Projection, F)
+
     template<class P, class G, FIT_ENABLE_IF_CONVERTIBLE(P, Projection), FIT_ENABLE_IF_CONVERTIBLE(G, F)>
     constexpr by_adaptor(P&& p, G&& f) 
     : Projection(fit::forward<P>(p)), F(fit::forward<G>(f))
@@ -199,6 +201,8 @@ struct by_adaptor<Projection, void> : Projection
         return always_ref(*this)(xs...);
     }
 
+    FIT_INHERIT_DEFAULT(by_adaptor, Projection)
+
     template<class P, FIT_ENABLE_IF_CONVERTIBLE(P, Projection)>
     constexpr by_adaptor(P&& p) 
     : Projection(fit::forward<P>(p))
diff --git a/fit/detail/compressed_pair.h b/fit/detail/compressed_pair.h
index 10bda63..1cff7c2 100644
--- a/fit/detail/compressed_pair.h
+++ b/fit/detail/compressed_pair.h
@@ -88,6 +88,8 @@ struct compressed_pair
     : FirstBase(fit::forward<X>(x)), SecondBase(fit::forward<Y>(y))
     {}
 
+    FIT_INHERIT_DEFAULT(compressed_pair, FirstBase, SecondBase)
+
     template<class Base, class... Xs>
     constexpr const Base& get_base(Xs&&... xs) const
     {
diff --git a/fit/detail/delegate.h b/fit/detail/delegate.h
index d2fdcce..8de6ea0 100644
--- a/fit/detail/delegate.h
+++ b/fit/detail/delegate.h
@@ -22,6 +22,14 @@
 #endif
 #endif
 
+#ifndef FIT_NO_STD_DEFAULT_CONSTRUCTIBLE
+#if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ < 7
+#define FIT_NO_STD_DEFAULT_CONSTRUCTIBLE 1
+#else
+#define FIT_NO_STD_DEFAULT_CONSTRUCTIBLE 0
+#endif
+#endif
+
 #define FIT_ENABLE_IF_CONVERTIBLE(...) \
     class=typename std::enable_if<std::is_convertible<__VA_ARGS__>::value>::type
 
@@ -31,15 +39,17 @@
 #define FIT_ENABLE_IF_CONSTRUCTIBLE(...) \
     class=typename std::enable_if<std::is_constructible<__VA_ARGS__>::value>::type
 
-#ifndef _MSC_VER
 #define FIT_INHERIT_DEFAULT(C, ...) \
     template<bool FitPrivateEnableBool_##__LINE__=true, \
     class=typename std::enable_if<FitPrivateEnableBool_##__LINE__ && fit::detail::is_default_constructible<__VA_ARGS__>::value>::type> \
     constexpr C() {}
-#else
-#define FIT_INHERIT_DEFAULT(C, ...) \
-    constexpr C() = default;
-#endif
+
+#define FIT_INHERIT_DEFAULT_EMPTY(C, ...) \
+    template<bool FitPrivateEnableBool_##__LINE__=true, \
+    class=typename std::enable_if<FitPrivateEnableBool_##__LINE__ && \
+        fit::detail::is_default_constructible<__VA_ARGS__>::value && std::is_empty<__VA_ARGS__>::value \
+    >::type> \
+    constexpr C() {}
 
 #if FIT_NO_TYPE_PACK_EXPANSION_IN_TEMPLATE
 
@@ -84,7 +94,11 @@ struct is_default_constructible_helper
 
 template<class... Xs>
 struct is_default_constructible
+#if FIT_NO_STD_DEFAULT_CONSTRUCTIBLE
 : and_<is_default_constructible_helper<Xs>...>
+#else
+: and_<std::is_default_constructible<Xs>...>
+#endif
 {};
 
 template<class T, class... Xs>
diff --git a/fit/function.h b/fit/function.h
index e01ac17..39ab5a0 100644
--- a/fit/function.h
+++ b/fit/function.h
@@ -44,12 +44,14 @@ struct reveal_static_const_factory
     template<class F>
     constexpr reveal_adaptor<F> operator=(const F& f) const
     {
+        static_assert(is_default_constructible<F>::value, "Static functions must be default constructible");
         return reveal_adaptor<F>(f);
     }
 #else
     template<class F>
     constexpr const reveal_adaptor<F>& operator=(const F&) const
     {
+        static_assert(is_default_constructible<F>::value, "Static functions must be default constructible");
         return static_const_var<reveal_adaptor<F>>();
     }
 #endif
diff --git a/fit/lazy.h b/fit/lazy.h
index 409de86..234ed44 100644
--- a/fit/lazy.h
+++ b/fit/lazy.h
@@ -151,7 +151,18 @@ struct lazy_invoker
     typedef detail::compressed_pair<F, Pack> base_type;
     typedef lazy_invoker fit_rewritable1_tag;
 
+#ifdef _MSC_VER
     FIT_INHERIT_CONSTRUCTOR(lazy_invoker, base_type)
+#else
+    FIT_INHERIT_DEFAULT_EMPTY(lazy_invoker, base_type)
+
+    template<class X, class Y, 
+        FIT_ENABLE_IF_CONSTRUCTIBLE(base_type, X&&, Y&&)
+    >
+    constexpr lazy_invoker(X&& x, Y&& y) 
+    : base_type(fit::forward<X>(x), fit::forward<Y>(y))
+    {}
+#endif
 
     template<class... Ts>
     constexpr const F& base_function(Ts&&... xs) const
diff --git a/fit/pack.h b/fit/pack.h
index 19fc17d..9609317 100644
--- a/fit/pack.h
+++ b/fit/pack.h
@@ -96,7 +96,7 @@ struct pack_holder
 : std::conditional<
         std::is_empty<T>::value && 
         std::is_literal_type<T>::value && 
-        is_default_constructible<T>::value, 
+        is_default_constructible<T>::value,
     alias_static<T, Tag>,
     alias<T, Tag>
 >
diff --git a/fit/placeholders.h b/fit/placeholders.h
index 6e220ca..0afb95b 100644
--- a/fit/placeholders.h
+++ b/fit/placeholders.h
@@ -167,7 +167,6 @@ FIT_FOREACH_UNARY_OP(FIT_UNARY_OP)
 template<int N>
 struct placeholder
 {
-
 #if FIT_HAS_MANGLE_OVERLOAD
     template<class... Ts>
     constexpr auto operator()(Ts&&... xs) const FIT_RETURNS 
@@ -252,7 +251,11 @@ struct partial_ap
 {
     T val;
 
-    FIT_DELGATE_CONSTRUCTOR(partial_ap, T, val);
+    FIT_INHERIT_DEFAULT_EMPTY(partial_ap, T)
+
+    template<class X, class... Xs, FIT_ENABLE_IF_CONSTRUCTIBLE(T, X&&, Xs&&...)>
+    constexpr partial_ap(X&& x, Xs&&... xs) : val(fit::forward<X>(x), fit::forward<Xs>(xs)...)
+    {}
 
     FIT_RETURNS_CLASS(partial_ap);
 
diff --git a/test/by.cpp b/test/by.cpp
index 9351d4b..1436e20 100644
--- a/test/by.cpp
+++ b/test/by.cpp
@@ -28,12 +28,14 @@ FIT_TEST_CASE()
     // Using mutable_ as a workaround on libc++, since mem_fn does not meet the
     // requirements of a FunctionObject
     FIT_TEST_CHECK(fit::by(fit::mutable_(std::mem_fn(&foo::x)), add)(foo(1), foo(2)) == 3);
+    static_assert(fit::detail::is_default_constructible<decltype(fit::by(select_x(), add))>::value, "Not default constructible");
 }
 
 FIT_TEST_CASE()
 {
     auto indirect_add = fit::by(*fit::_, fit::_ + fit::_);
     FIT_TEST_CHECK(indirect_add(std::unique_ptr<int>(new int(1)), std::unique_ptr<int>(new int(2))) == 3);
+    static_assert(fit::detail::is_default_constructible<decltype(indirect_add)>::value, "Not default constructible");
 }
 
 struct select_x_1
diff --git a/test/pack.cpp b/test/pack.cpp
index cd4d361..6358372 100644
--- a/test/pack.cpp
+++ b/test/pack.cpp
@@ -128,45 +128,80 @@ FIT_TEST_CASE()
     // FIT_TEST_CHECK(p(deref()) == 3);
 }
 
-class empty1
+struct empty1
 {};
 
-class empty2
+struct empty2
 {};
+
 FIT_TEST_CASE()
 {
-    static constexpr auto p1 = fit::pack(empty1());
-    FIT_TEST_CHECK(p1(fit::always(0)) == 0);
-    FIT_STATIC_TEST_CHECK(p1(fit::always(0)) == 0);
-#ifndef _MSC_VER
-    static_assert(std::is_empty<decltype(p1)>::value, "Pack not empty");
-#endif
-
-    static constexpr auto p2 = fit::pack(empty1(), empty2());
-    FIT_TEST_CHECK(p2(fit::always(0)) == 0);
-    FIT_STATIC_TEST_CHECK(p2(fit::always(0)) == 0);
-#ifndef _MSC_VER
-    static_assert(std::is_empty<decltype(p2)>::value, "Pack not empty");
-#endif
-
-    static constexpr auto p3 = fit::pack(empty1(), empty2(), empty1());
-    FIT_TEST_CHECK(p3(fit::always(0)) == 0);
-    FIT_STATIC_TEST_CHECK(p3(fit::always(0)) == 0);
-#ifndef _MSC_VER
-    static_assert(std::is_empty<decltype(p3)>::value, "Pack not empty");
-#endif
-
-    static constexpr auto p4 = fit::pack(empty1(), fit::pack(empty1(), empty2()));
-    FIT_TEST_CHECK(p4(fit::always(0)) == 0);
-    FIT_STATIC_TEST_CHECK(p4(fit::always(0)) == 0);
-#ifndef _MSC_VER
-    static_assert(std::is_empty<decltype(p4)>::value, "Pack not empty");
-#endif
-
-    static constexpr auto p5 = fit::pack(fit::pack(), fit::pack(fit::pack()), empty1(), fit::pack(empty1(), empty2()));
-    FIT_TEST_CHECK(p5(fit::always(0)) == 0);
-    FIT_STATIC_TEST_CHECK(p5(fit::always(0)) == 0);
-#ifndef _MSC_VER
-    static_assert(std::is_empty<decltype(p5)>::value, "Pack not empty");
-#endif
+    static_assert(fit::detail::is_default_constructible<empty1, empty2>::value, "Not default constructible");
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(empty1());
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
+
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(empty1(), empty2());
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(fit::pack(), fit::pack());
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(empty1(), empty2(), empty1());
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(empty1(), fit::pack(empty1(), empty2()));
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
+}
+
+FIT_TEST_CASE()
+{
+    static constexpr auto p = fit::pack(fit::pack(), fit::pack(fit::pack()), empty1(), fit::pack(empty1(), empty2()));
+    FIT_TEST_CHECK(p(fit::always(0)) == 0);
+    FIT_STATIC_TEST_CHECK(p(fit::always(0)) == 0);
+#ifndef _MSC_VER
+    static_assert(std::is_empty<decltype(p)>::value, "Pack not empty");
+#endif
+    static_assert(fit::detail::is_default_constructible<decltype(p)>::value, "Not default constructible");
 }
diff --git a/test/placeholders.cpp b/test/placeholders.cpp
index fa3436b..451dcb4 100644
--- a/test/placeholders.cpp
+++ b/test/placeholders.cpp
@@ -15,6 +15,20 @@ struct square
     FIT_PLACEHOLDER_TEST_CONSTEXPR auto operator()(T x) const FIT_RETURNS(x*x);
 };
 
+#define CHECK_DEFAULT_CONSTRUCTION_OP(op, name) \
+    static_assert(fit::detail::is_default_constructible<fit::operators::name>::value, "Operator not default constructible");
+
+FIT_TEST_CASE()
+{
+    static_assert(fit::detail::is_default_constructible<fit::placeholder<1>>::value, "Placeholder not default constructible");
+    static_assert(fit::detail::is_default_constructible<fit::placeholder<2>>::value, "Placeholder not default constructible");
+    static_assert(fit::detail::is_default_constructible<fit::placeholder<3>>::value, "Placeholder not default constructible");
+
+    FIT_FOREACH_BINARY_OP(CHECK_DEFAULT_CONSTRUCTION_OP)
+    FIT_FOREACH_ASSIGN_OP(CHECK_DEFAULT_CONSTRUCTION_OP)
+    FIT_FOREACH_UNARY_OP(CHECK_DEFAULT_CONSTRUCTION_OP)
+}
+
 FIT_TEST_CASE()
 {
     const auto x_square_add = 2 + (4*4);
@@ -43,6 +57,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_add)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_add)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_add(2, 1) == x_add);
     FIT_TEST_CHECK(f_add(2, 1) == x_add);
 
@@ -51,6 +66,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_subtract)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_subtract)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_subtract(2, 1) == x_subtract);
     FIT_TEST_CHECK(f_subtract(2, 1) == x_subtract);
 
@@ -59,6 +75,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_multiply)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_multiply)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_multiply(2, 1) == x_multiply);
     FIT_TEST_CHECK(f_multiply(2, 1) == x_multiply);
 
@@ -67,6 +84,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_divide)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_divide)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_divide(2, 1) == x_divide);
     FIT_TEST_CHECK(f_divide(2, 1) == x_divide);
 
@@ -75,6 +93,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_remainder)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_remainder)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_remainder(2, 1) == x_remainder);
     FIT_TEST_CHECK(f_remainder(2, 1) == x_remainder);
 
@@ -83,6 +102,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_right)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_shift_right)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_right(2, 1) == x_shift_right);
     FIT_TEST_CHECK(f_shift_right(2, 1) == x_shift_right);
 
@@ -91,6 +111,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_left)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_shift_left)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_left(2, 1) == x_shift_left);
     FIT_TEST_CHECK(f_shift_left(2, 1) == x_shift_left);
 
@@ -99,6 +120,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_greater_than)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than(2, 1) == x_greater_than);
     FIT_TEST_CHECK(f_greater_than(2, 1) == x_greater_than);
 
@@ -107,6 +129,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_less_than)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than(2, 1) == x_less_than);
     FIT_TEST_CHECK(f_less_than(2, 1) == x_less_than);
 
@@ -115,6 +138,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_less_than_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than_equal(2, 1) == x_less_than_equal);
     FIT_TEST_CHECK(f_less_than_equal(2, 1) == x_less_than_equal);
 
@@ -123,6 +147,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_greater_than_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than_equal(2, 1) == x_greater_than_equal);
     FIT_TEST_CHECK(f_greater_than_equal(2, 1) == x_greater_than_equal);
 
@@ -131,6 +156,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_equal(2, 1) == x_equal);
     FIT_TEST_CHECK(f_equal(2, 1) == x_equal);
 
@@ -139,6 +165,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_not_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_not_equal(2, 1) == x_not_equal);
     FIT_TEST_CHECK(f_not_equal(2, 1) == x_not_equal);
 
@@ -147,6 +174,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_and)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_bit_and)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_and(2, 1) == x_bit_and);
     FIT_TEST_CHECK(f_bit_and(2, 1) == x_bit_and);
 
@@ -155,6 +183,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_xor_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_xor_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_xor_(2, 1) == x_xor_);
     FIT_TEST_CHECK(f_xor_(2, 1) == x_xor_);
 
@@ -163,6 +192,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_or)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_bit_or)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_or(2, 1) == x_bit_or);
     FIT_TEST_CHECK(f_bit_or(2, 1) == x_bit_or);
 
@@ -171,6 +201,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_and_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_and_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_and_(true, false) == x_and_);
     FIT_TEST_CHECK(f_and_(true, false) == x_and_);
 
@@ -179,6 +210,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_or_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_or_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_or_(true, false) == x_or_);
     FIT_TEST_CHECK(f_or_(true, false) == x_or_);
 }
@@ -191,6 +223,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_not_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_not_(false) == x_not_);
     FIT_TEST_CHECK(f_not_(false) == x_not_);
 
@@ -199,6 +232,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_compl_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_compl_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_compl_(2) == x_compl_);
     FIT_TEST_CHECK(f_compl_(2) == x_compl_);
 
@@ -207,6 +241,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_unary_plus)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_unary_plus)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_unary_plus(2) == x_unary_plus);
     FIT_TEST_CHECK(f_unary_plus(2) == x_unary_plus);
 
@@ -215,6 +250,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_unary_subtract)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_unary_subtract)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_unary_subtract(2) == x_unary_subtract);
     FIT_TEST_CHECK(f_unary_subtract(2) == x_unary_subtract);
 
@@ -223,6 +259,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_dereference)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_dereference)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_dereference(&x_dereference) == x_dereference);
     FIT_TEST_CHECK(f_dereference(&x_dereference) == x_dereference);
 
@@ -233,6 +270,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_increment)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_increment)>::value, "Not default constructible");
     f_increment(x_increment);
     FIT_TEST_CHECK(x_increment == 3);
 
@@ -241,6 +279,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_decrement)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_decrement)>::value, "Not default constructible");
     f_decrement(x_decrement);
     FIT_TEST_CHECK(x_decrement == 1);
 #endif
@@ -256,6 +295,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_add)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_add)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_add(2, 1) == x_add);
     FIT_TEST_CHECK(f_add(2, 1) == x_add);
 
@@ -264,6 +304,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_subtract)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_subtract)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_subtract(2, 1) == x_subtract);
     FIT_TEST_CHECK(f_subtract(2, 1) == x_subtract);
 
@@ -272,6 +313,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_multiply)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_multiply)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_multiply(2, 1) == x_multiply);
     FIT_TEST_CHECK(f_multiply(2, 1) == x_multiply);
 
@@ -280,6 +322,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_divide)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_divide)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_divide(2, 1) == x_divide);
     FIT_TEST_CHECK(f_divide(2, 1) == x_divide);
 
@@ -288,6 +331,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_remainder)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_remainder)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_remainder(2, 1) == x_remainder);
     FIT_TEST_CHECK(f_remainder(2, 1) == x_remainder);
 
@@ -296,6 +340,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_right)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_shift_right)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_right(2, 1) == x_shift_right);
     FIT_TEST_CHECK(f_shift_right(2, 1) == x_shift_right);
 
@@ -304,6 +349,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_left)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_shift_left)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_left(2, 1) == x_shift_left);
     FIT_TEST_CHECK(f_shift_left(2, 1) == x_shift_left);
 
@@ -312,6 +358,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_greater_than)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than(2, 1) == x_greater_than);
     FIT_TEST_CHECK(f_greater_than(2, 1) == x_greater_than);
 
@@ -320,6 +367,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_less_than)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than(2, 1) == x_less_than);
     FIT_TEST_CHECK(f_less_than(2, 1) == x_less_than);
 
@@ -328,6 +376,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_less_than_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than_equal(2, 1) == x_less_than_equal);
     FIT_TEST_CHECK(f_less_than_equal(2, 1) == x_less_than_equal);
 
@@ -336,6 +385,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_greater_than_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than_equal(2, 1) == x_greater_than_equal);
     FIT_TEST_CHECK(f_greater_than_equal(2, 1) == x_greater_than_equal);
 
@@ -344,6 +394,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_equal(2, 1) == x_equal);
     FIT_TEST_CHECK(f_equal(2, 1) == x_equal);
 
@@ -352,6 +403,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_equal)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_not_equal)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_not_equal(2, 1) == x_not_equal);
     FIT_TEST_CHECK(f_not_equal(2, 1) == x_not_equal);
 
@@ -360,6 +412,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_and)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_bit_and)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_and(2, 1) == x_bit_and);
     FIT_TEST_CHECK(f_bit_and(2, 1) == x_bit_and);
 
@@ -368,6 +421,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_xor_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_xor_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_xor_(2, 1) == x_xor_);
     FIT_TEST_CHECK(f_xor_(2, 1) == x_xor_);
 
@@ -376,6 +430,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_or)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_bit_or)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_or(2, 1) == x_bit_or);
     FIT_TEST_CHECK(f_bit_or(2, 1) == x_bit_or);
 
@@ -384,6 +439,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_and_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_and_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_and_(true, false) == x_and_);
     FIT_TEST_CHECK(f_and_(true, false) == x_and_);
 
@@ -392,6 +448,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_or_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_or_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_or_(true, false) == x_or_);
     FIT_TEST_CHECK(f_or_(true, false) == x_or_);
 }
@@ -403,6 +460,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_add)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_add)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_add(1) == x_add);
     FIT_TEST_CHECK(f_add(1) == x_add);
 
@@ -411,6 +469,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_subtract)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_subtract)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_subtract(1) == x_subtract);
     FIT_TEST_CHECK(f_subtract(1) == x_subtract);
 
@@ -419,6 +478,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_multiply)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_multiply)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_multiply(1) == x_multiply);
     FIT_TEST_CHECK(f_multiply(1) == x_multiply);
 
@@ -427,6 +487,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_divide)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_divide)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_divide(1) == x_divide);
     FIT_TEST_CHECK(f_divide(1) == x_divide);
 
@@ -435,6 +496,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_remainder)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_remainder)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_remainder(1) == x_remainder);
     FIT_TEST_CHECK(f_remainder(1) == x_remainder);
 
@@ -443,6 +505,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_right)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_shift_right)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_right(1) == x_shift_right);
     FIT_TEST_CHECK(f_shift_right(1) == x_shift_right);
 
@@ -451,6 +514,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_left)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_shift_left)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_left(1) == x_shift_left);
     FIT_TEST_CHECK(f_shift_left(1) == x_shift_left);
 
@@ -459,6 +523,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_greater_than)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than(1) == x_greater_than);
     FIT_TEST_CHECK(f_greater_than(1) == x_greater_than);
 
@@ -467,6 +532,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_less_than)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than(1) == x_less_than);
     FIT_TEST_CHECK(f_less_than(1) == x_less_than);
 
@@ -475,6 +541,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_less_than_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than_equal(1) == x_less_than_equal);
     FIT_TEST_CHECK(f_less_than_equal(1) == x_less_than_equal);
 
@@ -483,6 +550,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_greater_than_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than_equal(1) == x_greater_than_equal);
     FIT_TEST_CHECK(f_greater_than_equal(1) == x_greater_than_equal);
 
@@ -491,6 +559,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_equal(1) == x_equal);
     FIT_TEST_CHECK(f_equal(1) == x_equal);
 
@@ -499,6 +568,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_not_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_not_equal(1) == x_not_equal);
     FIT_TEST_CHECK(f_not_equal(1) == x_not_equal);
 
@@ -507,6 +577,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_and)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_bit_and)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_and(1) == x_bit_and);
     FIT_TEST_CHECK(f_bit_and(1) == x_bit_and);
 
@@ -515,6 +586,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_xor_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_xor_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_xor_(1) == x_xor_);
     FIT_TEST_CHECK(f_xor_(1) == x_xor_);
 
@@ -523,6 +595,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_or)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_bit_or)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_or(1) == x_bit_or);
     FIT_TEST_CHECK(f_bit_or(1) == x_bit_or);
 
@@ -531,6 +604,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_and_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_and_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_and_(false) == x_and_);
     FIT_TEST_CHECK(f_and_(false) == x_and_);
 
@@ -539,6 +613,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_or_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_or_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_or_(false) == x_or_);
     FIT_TEST_CHECK(f_or_(false) == x_or_);
 }
@@ -550,6 +625,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_add)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_add)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_add(2) == x_add);
     FIT_TEST_CHECK(f_add(2) == x_add);
 
@@ -558,6 +634,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_subtract)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_subtract)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_subtract(2) == x_subtract);
     FIT_TEST_CHECK(f_subtract(2) == x_subtract);
 
@@ -566,6 +643,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_multiply)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_multiply)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_multiply(2) == x_multiply);
     FIT_TEST_CHECK(f_multiply(2) == x_multiply);
 
@@ -574,6 +652,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_divide)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_divide)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_divide(2) == x_divide);
     FIT_TEST_CHECK(f_divide(2) == x_divide);
 
@@ -582,6 +661,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_remainder)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_remainder)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_remainder(2) == x_remainder);
     FIT_TEST_CHECK(f_remainder(2) == x_remainder);
 
@@ -590,6 +670,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_right)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_shift_right)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_right(2) == x_shift_right);
     FIT_TEST_CHECK(f_shift_right(2) == x_shift_right);
 
@@ -598,6 +679,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_shift_left)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_shift_left)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_shift_left(2) == x_shift_left);
     FIT_TEST_CHECK(f_shift_left(2) == x_shift_left);
 
@@ -606,6 +688,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_greater_than)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than(2) == x_greater_than);
     FIT_TEST_CHECK(f_greater_than(2) == x_greater_than);
 
@@ -614,6 +697,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_less_than)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than(2) == x_less_than);
     FIT_TEST_CHECK(f_less_than(2) == x_less_than);
 
@@ -622,6 +706,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_less_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_less_than_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_less_than_equal(2) == x_less_than_equal);
     FIT_TEST_CHECK(f_less_than_equal(2) == x_less_than_equal);
 
@@ -630,6 +715,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_greater_than_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_greater_than_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_greater_than_equal(2) == x_greater_than_equal);
     FIT_TEST_CHECK(f_greater_than_equal(2) == x_greater_than_equal);
 
@@ -638,6 +724,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_equal(2) == x_equal);
     FIT_TEST_CHECK(f_equal(2) == x_equal);
 
@@ -646,6 +733,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_equal)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_not_equal)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_not_equal(2) == x_not_equal);
     FIT_TEST_CHECK(f_not_equal(2) == x_not_equal);
 
@@ -654,6 +742,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_and)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_bit_and)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_and(2) == x_bit_and);
     FIT_TEST_CHECK(f_bit_and(2) == x_bit_and);
 
@@ -662,6 +751,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_xor_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_xor_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_xor_(2) == x_xor_);
     FIT_TEST_CHECK(f_xor_(2) == x_xor_);
 
@@ -670,6 +760,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_bit_or)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_bit_or)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_bit_or(2) == x_bit_or);
     FIT_TEST_CHECK(f_bit_or(2) == x_bit_or);
 
@@ -678,6 +769,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_and_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_and_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_and_(true) == x_and_);
     FIT_TEST_CHECK(f_and_(true) == x_and_);
 
@@ -686,6 +778,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_or_)>::value, "Not copyable");
 #endif
+    static_assert(!fit::detail::is_default_constructible<decltype(f_or_)>::value, "default constructible");
     FIT_STATIC_TEST_CHECK(f_or_(true) == x_or_);
     FIT_TEST_CHECK(f_or_(true) == x_or_);
 }
@@ -698,6 +791,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_not_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_not_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_not_(false) == x_not_);
     FIT_TEST_CHECK(f_not_(false) == x_not_);
 
@@ -706,6 +800,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_compl_)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_compl_)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_compl_(2) == x_compl_);
     FIT_TEST_CHECK(f_compl_(2) == x_compl_);
 
@@ -714,6 +809,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_unary_plus)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_unary_plus)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_unary_plus(2) == x_unary_plus);
     FIT_TEST_CHECK(f_unary_plus(2) == x_unary_plus);
 
@@ -722,6 +818,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_unary_subtract)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_unary_subtract)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_unary_subtract(2) == x_unary_subtract);
     FIT_TEST_CHECK(f_unary_subtract(2) == x_unary_subtract);
 
@@ -730,6 +827,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_dereference)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_dereference)>::value, "Not default constructible");
     FIT_STATIC_TEST_CHECK(f_dereference(&x_dereference) == x_dereference);
     FIT_TEST_CHECK(f_dereference(&x_dereference) == x_dereference);
 
@@ -740,6 +838,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_increment)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_increment)>::value, "Not default constructible");
     f_increment(x_increment);
     FIT_TEST_CHECK(x_increment == 3);
 
@@ -748,6 +847,7 @@ FIT_TEST_CASE()
 #if defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ > 6   
     static_assert(std::is_copy_constructible<decltype(f_decrement)>::value, "Not copyable");
 #endif
+    static_assert(fit::detail::is_default_constructible<decltype(f_decrement)>::value, "Not default constructible");
     f_decrement(x_decrement);
     FIT_TEST_CHECK(x_decrement == 1);
 #endif