[v3 PATCH] LWG 2766, LWG 2749

[Jonathan Wakely]

On 26/11/16 14:47 +0200, Ville Voutilainen wrote:
>Updated patches attached, and tested with the full testsuite on Linux-PPC64.

Both patches are OK for trunk with the minor tweaks noted below.
Thanks.


>diff --git a/libstdc++-v3/include/bits/stl_pair.h b/libstdc++-v3/include/bits/stl_pair.h
>index ef52538..981dbeb 100644
>--- a/libstdc++-v3/include/bits/stl_pair.h
>+++ b/libstdc++-v3/include/bits/stl_pair.h
>@@ -478,6 +478,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>     swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
>     noexcept(noexcept(__x.swap(__y)))
>     { __x.swap(__y); }
>+
>+#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
>+  template<typename _T1, typename _T2>
>+    inline
>+    typename enable_if<!__and_<__is_swappable<_T1>,
>+			       __is_swappable<_T2>>::value>::type
>+    swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
>+#endif
> #endif // __cplusplus >= 201103L
>
>   /**
>diff --git a/libstdc++-v3/include/bits/unique_ptr.h b/libstdc++-v3/include/bits/unique_ptr.h
>index f9ec60f..21b0bac 100644
>--- a/libstdc++-v3/include/bits/unique_ptr.h
>+++ b/libstdc++-v3/include/bits/unique_ptr.h
>@@ -649,6 +649,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>     swap(unique_ptr<_Tp, _Dp>& __x,
> 	 unique_ptr<_Tp, _Dp>& __y) noexcept
>     { __x.swap(__y); }

Insert a blank line here please.

>+#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
>+  template<typename _Tp, typename _Dp>
>+    inline
>+    typename enable_if<!__is_swappable<_Dp>::value>::type
>+    swap(unique_ptr<_Tp, _Dp>&,
>+	 unique_ptr<_Tp, _Dp>&) = delete;
>+#endif
>
>   template<typename _Tp, typename _Dp,
> 	   typename _Up, typename _Ep>
>diff --git a/libstdc++-v3/include/std/array b/libstdc++-v3/include/std/array
>index 3ab0355..86100b5 100644
>--- a/libstdc++-v3/include/std/array
>+++ b/libstdc++-v3/include/std/array
>@@ -287,6 +287,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
>     swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
>     noexcept(noexcept(__one.swap(__two)))
>     { __one.swap(__two); }

Insert a blank line here please.

>+#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
>+  template<typename _Tp, std::size_t _Nm>
>+    inline
>+    typename enable_if<
>+      !_GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::_Is_swappable::value>::type
>+    swap(array<_Tp, _Nm>&, array<_Tp, _Nm>&) = delete;
>+#endif
>
>   template<std::size_t _Int, typename _Tp, std::size_t _Nm>
>     constexpr _Tp&


>diff --git a/libstdc++-v3/include/std/tuple b/libstdc++-v3/include/std/tuple
>index 63cacd4..8952750 100644
>--- a/libstdc++-v3/include/std/tuple
>+++ b/libstdc++-v3/include/std/tuple
>@@ -1442,17 +1442,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>     forward_as_tuple(_Elements&&... __args) noexcept
>     { return tuple<_Elements&&...>(std::forward<_Elements>(__args)...); }
>
>-  template<typename... _Tps>
>-    struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
>-    { };
>-
>-  // Internal type trait that allows us to sfinae-protect tuple_cat.
>-  template<typename _Tp>
>-    struct __is_tuple_like
>-    : public __is_tuple_like_impl<typename std::remove_cv
>-            <typename std::remove_reference<_Tp>::type>::type>::type
>-    { };
>-
>   template<size_t, typename, typename, size_t>
>     struct __make_tuple_impl;
>
>@@ -1596,6 +1585,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>     swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
>     noexcept(noexcept(__x.swap(__y)))
>     { __x.swap(__y); }

Insert a blank line here please.

>+#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
>+  template<typename... _Elements>
>+    inline
>+    typename enable_if<!__and_<__is_swappable<_Elements>...>::value>::type
>+    swap(tuple<_Elements...>&, tuple<_Elements...>&) = delete;
>+#endif
>
>   // A class (and instance) which can be used in 'tie' when an element
>   // of a tuple is not required
>diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
>index e5f2bba..49f76cc 100644
>--- a/libstdc++-v3/include/std/type_traits
>+++ b/libstdc++-v3/include/std/type_traits
>@@ -2593,9 +2593,28 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>   template <typename _Tp>
>     struct __is_nothrow_swappable;
>
>+  template<typename... _Elements>
>+    class tuple;
>+
>+  template<typename>
>+    struct __is_tuple_like_impl : false_type
>+    { };
>+
>+  template<typename... _Tps>
>+    struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
>+    { };
>+
>+  // Internal type trait that allows us to sfinae-protect tuple_cat.
>+  template<typename _Tp>
>+    struct __is_tuple_like
>+    : public __is_tuple_like_impl<typename std::remove_cv
>+            <typename std::remove_reference<_Tp>::type>::type>::type

We can lose the std:: quals here.

>+    { };
>+
>   template<typename _Tp>
>     inline
>-    typename enable_if<__and_<is_move_constructible<_Tp>,
>+    typename enable_if<__and_<__not_<__is_tuple_like<_Tp>>,
>+			      is_move_constructible<_Tp>,
> 			      is_move_assignable<_Tp>>::value>::type
>     swap(_Tp&, _Tp&)
>     noexcept(__and_<is_nothrow_move_constructible<_Tp>,