Use constexpr addressof in optional, SFINAE housekeeping for any, optional and tuple.

Use constexpr addressof in optional, SFINAE housekeeping
for any, optional and tuple.
* include/std/any (__do_emplace(_Args&&...)): New.
(__do_emplace(initializer_list<_Up>, _Args&&...)): Likewise.
(__any_constructible): Likewise.
(__any_constructible_t): Use __any_constructible.
(operator=(_ValueType&&)): SFINAE in the return type.
(emplace(_Args&&...)): Likewise.
(emplace(initializer_list<_Up>, _Args&&...)): Likewise.
* include/std/optional (_Has_addressof_mem): Remove.
(_Has_addressof_free): Likewise.
(_Has_addressof): Likewise.
(__constexpr_addressof(_Tp&)): Likewise.
(operator->): Use std::__addressof.
* include/std/tuple (operator=(const tuple<_UElements...>&)):
SFINAE in return type.
(operator=(tuple<_UElements...>&&)): Likewise.
* testsuite/20_util/any/misc/any_cast_neg.cc: Adjust.

From-SVN: r242390
This commit is contained in:
Ville Voutilainen 2016-11-14 17:30:37 +02:00 committed by Ville Voutilainen
parent ebd9509a2d
commit ca9e949f2e
5 changed files with 73 additions and 78 deletions

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@ -1,3 +1,24 @@
2016-11-14 Ville Voutilainen <ville.voutilainen@gmail.com>
Use constexpr addressof in optional, SFINAE housekeeping
for any, optional and tuple.
* include/std/any (__do_emplace(_Args&&...)): New.
(__do_emplace(initializer_list<_Up>, _Args&&...)): Likewise.
(__any_constructible): Likewise.
(__any_constructible_t): Use __any_constructible.
(operator=(_ValueType&&)): SFINAE in the return type.
(emplace(_Args&&...)): Likewise.
(emplace(initializer_list<_Up>, _Args&&...)): Likewise.
* include/std/optional (_Has_addressof_mem): Remove.
(_Has_addressof_free): Likewise.
(_Has_addressof): Likewise.
(__constexpr_addressof(_Tp&)): Likewise.
(operator->): Use std::__addressof.
* include/std/tuple (operator=(const tuple<_UElements...>&)):
SFINAE in return type.
(operator=(tuple<_UElements...>&&)): Likewise.
* testsuite/20_util/any/misc/any_cast_neg.cc: Adjust.
2016-11-14 Jonathan Wakely <jwakely@redhat.com>
* include/bits/move.h (addressof(const _Tp&&)): Add deleted overload,

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@ -108,6 +108,27 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp, typename _Decayed = decay_t<_Tp>>
using _Decay = enable_if_t<!is_same<_Decayed, any>::value, _Decayed>;
/// Emplace with an object created from @p __args as the contained object.
template <typename _Tp, typename... _Args,
typename _Mgr = _Manager<_Tp>>
void __do_emplace(_Args&&... __args)
{
reset();
_M_manager = &_Mgr::_S_manage;
_Mgr::_S_create(_M_storage, std::forward<_Args>(__args)...);
}
/// Emplace with an object created from @p __il and @p __args as
/// the contained object.
template <typename _Tp, typename _Up, typename... _Args,
typename _Mgr = _Manager<_Tp>>
void __do_emplace(initializer_list<_Up> __il, _Args&&... __args)
{
reset();
_M_manager = &_Mgr::_S_manage;
_Mgr::_S_create(_M_storage, __il, std::forward<_Args>(__args)...);
}
public:
// construct/destruct
@ -144,11 +165,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
}
template <typename _Res, typename _Tp, typename... _Args>
using __any_constructible =
enable_if<__and_<is_copy_constructible<_Tp>,
is_constructible<_Tp, _Args...>>::value,
_Res>;
template <typename _Tp, typename... _Args>
using __any_constructible_t =
enable_if_t<__and_<is_copy_constructible<_Tp>,
is_constructible<_Tp, _Args...>>::value,
bool>;
typename __any_constructible<bool, _Tp, _Args...>::type;
/// Construct with a copy of @p __value as the contained object.
template <typename _ValueType, typename _Tp = _Decay<_ValueType>,
@ -233,9 +258,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
/// Store a copy of @p __rhs as the contained object.
template<typename _ValueType,
typename _Tp = _Decay<_ValueType>>
enable_if_t<is_copy_constructible<_Tp>::value, any&>
template<typename _ValueType>
enable_if_t<is_copy_constructible<_Decay<_ValueType>>::value, any&>
operator=(_ValueType&& __rhs)
{
*this = any(std::forward<_ValueType>(__rhs));
@ -243,29 +267,26 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
/// Emplace with an object created from @p __args as the contained object.
template <typename _ValueType, typename... _Args,
typename _Tp = _Decay<_ValueType>,
typename _Mgr = _Manager<_Tp>,
__any_constructible_t<_Tp, _Args&&...> = false>
void emplace(_Args&&... __args)
template <typename _ValueType, typename... _Args>
typename __any_constructible<void,
_Decay<_ValueType>, _Args&&...>::type
emplace(_Args&&... __args)
{
reset();
_M_manager = &_Mgr::_S_manage;
_Mgr::_S_create(_M_storage, std::forward<_Args>(__args)...);
__do_emplace<_Decay<_ValueType>>
(std::forward<_Args>(__args)...);
}
/// Emplace with an object created from @p __il and @p __args as
/// the contained object.
template <typename _ValueType, typename _Up, typename... _Args,
typename _Tp = _Decay<_ValueType>,
typename _Mgr = _Manager<_Tp>,
__any_constructible_t<_Tp, initializer_list<_Up>,
_Args&&...> = false>
void emplace(initializer_list<_Up> __il, _Args&&... __args)
template <typename _ValueType, typename _Up, typename... _Args>
typename __any_constructible<void,
_Decay<_ValueType>,
initializer_list<_Up>,
_Args&&...>::type
emplace(initializer_list<_Up> __il, _Args&&... __args)
{
reset();
_M_manager = &_Mgr::_S_manage;
_Mgr::_S_create(_M_storage, __il, std::forward<_Args>(__args)...);
__do_emplace<_Decay<_ValueType>, _Up>
(__il, std::forward<_Args>(__args)...);
}
// modifiers

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@ -96,53 +96,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
__throw_bad_optional_access(const char* __s)
{ _GLIBCXX_THROW_OR_ABORT(bad_optional_access(__s)); }
template<typename _Tp, typename = void>
struct _Has_addressof_mem : std::false_type { };
template<typename _Tp>
struct _Has_addressof_mem<_Tp,
__void_t<decltype( std::declval<const _Tp&>().operator&() )>
>
: std::true_type { };
template<typename _Tp, typename = void>
struct _Has_addressof_free : std::false_type { };
template<typename _Tp>
struct _Has_addressof_free<_Tp,
__void_t<decltype( operator&(std::declval<const _Tp&>()) )>
>
: std::true_type { };
/**
* @brief Trait that detects the presence of an overloaded unary operator&.
*
* Practically speaking this detects the presence of such an operator when
* called on a const-qualified lvalue (e.g.
* declval<const _Tp&>().operator&()).
*/
template<typename _Tp>
struct _Has_addressof
: std::__or_<_Has_addressof_mem<_Tp>, _Has_addressof_free<_Tp>>::type
{ };
/**
* @brief An overload that attempts to take the address of an lvalue as a
* constant expression. Falls back to __addressof in the presence of an
* overloaded addressof operator (unary operator&), in which case the call
* will not be a constant expression.
*/
template<typename _Tp, enable_if_t<!_Has_addressof<_Tp>::value, int>...>
constexpr _Tp* __constexpr_addressof(_Tp& __t)
{ return &__t; }
/**
* @brief Fallback overload that defers to __addressof.
*/
template<typename _Tp, enable_if_t<_Has_addressof<_Tp>::value, int>...>
inline _Tp* __constexpr_addressof(_Tp& __t)
{ return std::__addressof(__t); }
/**
* @brief Class template that holds the necessary state for @ref optional
* and that has the responsibility for construction and the special members.
@ -681,7 +634,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// Observers.
constexpr const _Tp*
operator->() const
{ return __constexpr_addressof(this->_M_get()); }
{ return std::__addressof(this->_M_get()); }
_Tp*
operator->()

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@ -846,20 +846,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
return *this;
}
template<typename... _UElements, typename = typename
template<typename... _UElements>
typename
enable_if<sizeof...(_UElements)
== sizeof...(_Elements)>::type>
tuple&
== sizeof...(_Elements), tuple&>::type
operator=(const tuple<_UElements...>& __in)
{
static_cast<_Inherited&>(*this) = __in;
return *this;
}
template<typename... _UElements, typename = typename
template<typename... _UElements>
typename
enable_if<sizeof...(_UElements)
== sizeof...(_Elements)>::type>
tuple&
== sizeof...(_Elements), tuple&>::type
operator=(tuple<_UElements...>&& __in)
{
static_cast<_Inherited&>(*this) = std::move(__in);

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@ -26,5 +26,5 @@ void test01()
using std::any_cast;
const any y(1);
any_cast<int&>(y); // { dg-error "qualifiers" "" { target { *-*-* } } 432 }
any_cast<int&>(y); // { dg-error "qualifiers" "" { target { *-*-* } } 453 }
}