template <typename _Tp, bool = is_array<_Tp>::value>
struct __libfund_v1 { using type = _Tp; };
- // helper for _Compatible
- template<typename _From_type, typename _To_type>
- struct __sp_compatible
- : is_convertible<_From_type*, _To_type*>::type
- { };
-
- template<size_t _Nm, typename _Tp>
- struct __sp_compatible<_Tp[_Nm], _Tp[]>
- : true_type
- { };
-
- template<size_t _Nm, typename _Tp>
- struct __sp_compatible<_Tp[_Nm], const _Tp[]>
- : true_type
- { };
-
// Partial specialization for base class of experimental::shared_ptr<T>
// (i.e. the non-array form of experimental::shared_ptr)
template<typename _Tp, _Lock_policy _Lp>
class __shared_ptr<__libfund_v1<_Tp, false>, _Lp>
: private __shared_ptr<_Tp, _Lp>
{
- template<typename _Tp1, typename _Res = void>
+ // For non-arrays, Y* is compatible with T* if Y* is convertible to T*.
+ template<typename _Yp, typename _Res = void>
using _Compatible
- = enable_if_t<__sp_compatible<_Tp1, _Tp>::value, _Res>;
+ = enable_if_t<experimental::is_convertible_v<_Yp*, _Tp*>, _Res>;
+
+ template<typename _Yp, typename _Del,
+ typename _Ptr = typename unique_ptr<_Yp, _Del>::pointer,
+ typename _Res = void>
+ using _UniqCompatible = enable_if_t<
+ experimental::is_convertible_v<_Yp*, _Tp*>
+ && experimental::is_convertible_v<_Ptr, _Tp*>,
+ _Res>;
using _Base_type = __shared_ptr<_Tp>;
- _Base_type& _M_get_base() { return *this;}
- const _Base_type& _M_get_base() const { return *this;}
+ _Base_type& _M_get_base() { return *this; }
+ const _Base_type& _M_get_base() const { return *this; }
public:
using element_type = _Tp;
constexpr __shared_ptr() noexcept = default;
- template<typename _Tp1>
- explicit __shared_ptr(_Tp1* __p)
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
+ explicit
+ __shared_ptr(_Tp1* __p)
: _Base_type(__p)
{ }
- template<typename _Tp1, typename _Deleter>
+ template<typename _Tp1, typename _Deleter, typename = _Compatible<_Tp1>>
__shared_ptr(_Tp1* __p, _Deleter __d)
: _Base_type(__p, __d)
{ }
- template<typename _Tp1, typename _Deleter, typename _Alloc>
+ template<typename _Tp1, typename _Deleter, typename _Alloc,
+ typename = _Compatible<_Tp1>>
__shared_ptr(_Tp1* __p, _Deleter __d, _Alloc __a)
: _Base_type(__p, __d, __a)
{ }
: _Base_type(std::move((__r._M_get_base())))
{ }
- template<typename _Tp1>
- explicit __shared_ptr(const __weak_ptr<__libfund_v1<_Tp1>, _Lp>& __r)
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
+ explicit
+ __shared_ptr(const __weak_ptr<__libfund_v1<_Tp1>, _Lp>& __r)
: _Base_type(__r._M_get_base())
{ }
- template<typename _Tp1, typename _Del, typename
- = _Compatible<remove_pointer_t<
- typename unique_ptr<_Tp1, _Del>::pointer>>>
- __shared_ptr(std::unique_ptr<_Tp1, _Del>&& __r)
- : _Base_type(std::move(__r))
- { }
+ template<typename _Tp1, typename _Del,
+ typename = _UniqCompatible<_Tp1, _Del>>
+ __shared_ptr(unique_ptr<_Tp1, _Del>&& __r)
+ : _Base_type(std::move(__r))
+ { }
#if _GLIBCXX_USE_DEPRECATED
// Postcondition: use_count() == 1 and __r.get() == 0
- template<typename _Tp1>
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
__shared_ptr(std::auto_ptr<_Tp1>&& __r)
: _Base_type(std::move(__r))
{ }
{ __shared_ptr(nullptr).swap(*this); }
template<typename _Tp1>
- void
+ _Compatible<_Tp1>
reset(_Tp1* __p)
{
_GLIBCXX_DEBUG_ASSERT(__p == 0 || __p != get());
}
template<typename _Tp1, typename _Deleter>
- void
+ _Compatible<_Tp1>
reset(_Tp1* __p, _Deleter __d)
{ __shared_ptr(__p, __d).swap(*this); }
template<typename _Tp1, typename _Deleter, typename _Alloc>
- void
+ _Compatible<_Tp1>
reset(_Tp1* __p, _Deleter __d, _Alloc __a)
{ __shared_ptr(__p, __d, std::move(__a)).swap(*this); }
return *this;
}
- template<typename _Tp1>
- _Compatible<_Tp1, __shared_ptr&>
- operator=(std::unique_ptr<_Tp1>&& __r)
+ template<typename _Tp1, typename _Del>
+ _UniqCompatible<_Tp1, _Del, __shared_ptr&>
+ operator=(unique_ptr<_Tp1, _Del>&& __r)
{
_Base_type::operator=(std::move(__r));
return *this;
friend _Del* get_deleter(const __shared_ptr<_Tp1, _Lp1>&) noexcept;
};
+ // Helper traits for shared_ptr of array:
+
+ // Trait that tests if Y* is compatible with T*, for shared_ptr purposes.
+ template<typename _Yp, typename _Tp>
+ struct __sp_compatible
+ : is_convertible<_Yp*, _Tp*>::type
+ { };
+
+ template<size_t _Nm, typename _Tp>
+ struct __sp_compatible<_Tp[_Nm], _Tp[]>
+ : true_type
+ { };
+
+ template<size_t _Nm, typename _Tp>
+ struct __sp_compatible<_Tp[_Nm], const _Tp[]>
+ : true_type
+ { };
+
+ template<typename _Yp, typename _Tp>
+ constexpr bool __sp_compatible_v
+ = __sp_compatible<_Yp, _Tp>::value;
+
+ // Test conversion from Y(*)[N] to U(*)[N] without forming invalid type Y[N].
+ template<typename _Up, size_t _Nm, typename _Yp, typename = void>
+ struct __sp_is_constructible_arrN
+ : false_type
+ { };
+
+ template<typename _Up, size_t _Nm, typename _Yp>
+ struct __sp_is_constructible_arrN<_Up, _Nm, _Yp, __void_t<_Yp[_Nm]>>
+ : is_convertible<_Yp(*)[_Nm], _Up(*)[_Nm]>::type
+ { };
+
+ // Test conversion from Y(*)[] to U(*)[] without forming invalid type Y[].
+ template<typename _Up, typename _Yp, typename = void>
+ struct __sp_is_constructible_arr
+ : false_type
+ { };
+
+ template<typename _Up, typename _Yp>
+ struct __sp_is_constructible_arr<_Up, _Yp, __void_t<_Yp[]>>
+ : is_convertible<_Yp(*)[], _Up(*)[]>::type
+ { };
+
+ // Trait to check if shared_ptr<T> can be constructed from Y*.
+ template<typename _Tp, typename _Yp>
+ struct __sp_is_constructible;
+
+ // When T is U[N], Y(*)[N] shall be convertible to T*;
+ template<typename _Up, size_t _Nm, typename _Yp>
+ struct __sp_is_constructible<_Up[_Nm], _Yp>
+ : __sp_is_constructible_arrN<_Up, _Nm, _Yp>::type
+ { };
+
+ // when T is U[], Y(*)[] shall be convertible to T*;
+ template<typename _Up, typename _Yp>
+ struct __sp_is_constructible<_Up[], _Yp>
+ : __sp_is_constructible_arr<_Up, _Yp>::type
+ { };
+
+ // otherwise, Y* shall be convertible to T*.
+ template<typename _Tp, typename _Yp>
+ struct __sp_is_constructible
+ : is_convertible<_Yp*, _Tp*>::type
+ { };
+
+ template<typename _Tp, typename _Yp>
+ constexpr bool __sp_is_constructible_v
+ = __sp_is_constructible<_Tp, _Yp>::value;
+
+
// Partial specialization for base class of experimental::shared_ptr<T[N]>
// and experimental::shared_ptr<T[]> (i.e. the array forms).
template<typename _Tp, _Lock_policy _Lp>
{ delete [] __p; }
};
+ // Constraint for constructing/resetting with a pointer of type _Yp*:
+ template<typename _Yp>
+ using _SafeConv = enable_if_t<__sp_is_constructible_v<_Tp, _Yp>>;
+
+ // Constraint for constructing/assigning from smart_pointer<_Tp1>:
template<typename _Tp1, typename _Res = void>
- using _Compatible
- = enable_if_t<__sp_compatible<_Tp1, _Tp>::value, _Res>;
+ using _Compatible = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>;
+
+ // Constraint for constructing/assigning from unique_ptr<_Tp1, _Del>:
+ template<typename _Tp1, typename _Del,
+ typename _Ptr = typename unique_ptr<_Tp1, _Del>::pointer,
+ typename _Res = void>
+ using _UniqCompatible = enable_if_t<
+ __sp_compatible_v<_Tp1, _Tp>
+ && experimental::is_convertible_v<_Ptr, element_type*>,
+ _Res>;
using _Base_type = __shared_ptr<element_type>;
- _Base_type& _M_get_base() { return *this;}
- const _Base_type& _M_get_base() const { return *this;}
+ _Base_type& _M_get_base() { return *this; }
+ const _Base_type& _M_get_base() const { return *this; }
public:
constexpr __shared_ptr() noexcept
: _Base_type()
{ }
- template<typename _Tp1>
- explicit __shared_ptr(_Tp1* __p)
+ template<typename _Tp1, typename = _SafeConv<_Tp1>>
+ explicit
+ __shared_ptr(_Tp1* __p)
: _Base_type(__p, _Array_deleter())
{ }
- template<typename _Tp1, typename _Deleter>
+ template<typename _Tp1, typename _Deleter, typename = _SafeConv<_Tp1>>
__shared_ptr(_Tp1* __p, _Deleter __d)
: _Base_type(__p, __d)
{ }
- template<typename _Tp1, typename _Deleter, typename _Alloc>
+ template<typename _Tp1, typename _Deleter, typename _Alloc,
+ typename = _SafeConv<_Tp1>>
__shared_ptr(_Tp1* __p, _Deleter __d, _Alloc __a)
: _Base_type(__p, __d, __a)
{ }
: _Base_type(std::move((__r._M_get_base())))
{ }
- template<typename _Tp1>
- explicit __shared_ptr(const __weak_ptr<__libfund_v1<_Tp1>, _Lp>& __r)
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
+ explicit
+ __shared_ptr(const __weak_ptr<__libfund_v1<_Tp1>, _Lp>& __r)
: _Base_type(__r._M_get_base())
{ }
- template<typename _Tp1, typename _Del, typename
- = _Compatible<remove_pointer_t<
- typename unique_ptr<_Tp1, _Del>::pointer>>>
- __shared_ptr(std::unique_ptr<_Tp1, _Del>&& __r)
- : _Base_type(std::move(__r))
- { }
+ template<typename _Tp1, typename _Del,
+ typename = _UniqCompatible<_Tp1, _Del>>
+ __shared_ptr(unique_ptr<_Tp1, _Del>&& __r)
+ : _Base_type(std::move(__r))
+ { }
#if _GLIBCXX_USE_DEPRECATED
// Postcondition: use_count() == 1 and __r.get() == 0
- template<typename _Tp1>
- __shared_ptr(std::auto_ptr<_Tp1>&& __r)
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
+ __shared_ptr(auto_ptr<_Tp1>&& __r)
: _Base_type(std::move(__r))
{ }
#endif
{ __shared_ptr(nullptr).swap(*this); }
template<typename _Tp1>
- void
+ _SafeConv<_Tp1>
reset(_Tp1* __p)
{
_GLIBCXX_DEBUG_ASSERT(__p == 0 || __p != get());
}
template<typename _Tp1, typename _Deleter>
- void
+ _SafeConv<_Tp1>
reset(_Tp1* __p, _Deleter __d)
{ __shared_ptr(__p, __d).swap(*this); }
template<typename _Tp1, typename _Deleter, typename _Alloc>
- void
+ _SafeConv<_Tp1>
reset(_Tp1* __p, _Deleter __d, _Alloc __a)
{ __shared_ptr(__p, __d, std::move(__a)).swap(*this); }
return *this;
}
- template<typename _Tp1>
- _Compatible<_Tp1, __shared_ptr&>
- operator=(std::unique_ptr<_Tp1>&& __r)
+ template<typename _Tp1, typename _Del>
+ _UniqCompatible<_Tp1, _Del, __shared_ptr&>
+ operator=(unique_ptr<_Tp1, _Del>&& __r)
{
_Base_type::operator=(std::move(__r));
return *this;
#if _GLIBCXX_USE_DEPRECATED
template<typename _Tp1>
_Compatible<_Tp1, __shared_ptr&>
- operator=(std::auto_ptr<_Tp1>&& __r)
+ operator=(auto_ptr<_Tp1>&& __r)
{
_Base_type::operator=(std::move(__r));
return *this;
{
template<typename _Tp1, typename _Res = void>
using _Compatible
- = enable_if_t<__sp_compatible<_Tp1, _Tp>::value, _Res>;
+ = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>;
using _Base_type = __weak_ptr<remove_extent_t<_Tp>>;
- _Base_type& _M_get_base() { return *this;}
+ _Base_type& _M_get_base() { return *this; }
const _Base_type& _M_get_base() const { return *this; }
public:
template<typename _Tp>
class shared_ptr : public __shared_ptr<_Tp>
{
+ using _Base_type = __shared_ptr<_Tp>;
+
+ public:
+ using element_type = typename _Base_type::element_type;
+
+ private:
+ // Constraint for construction from a pointer of type _Yp*:
+ template<typename _Yp>
+ using _SafeConv = enable_if_t<__sp_is_constructible_v<_Tp, _Yp>>;
+
template<typename _Tp1, typename _Res = void>
using _Compatible
- = enable_if_t<__sp_compatible<_Tp1, _Tp>::value, _Res>;
+ = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>;
- using _Base_type = __shared_ptr<_Tp>;
+ template<typename _Tp1, typename _Del,
+ typename _Ptr = typename unique_ptr<_Tp1, _Del>::pointer,
+ typename _Res = void>
+ using _UniqCompatible = enable_if_t<
+ __sp_compatible_v<_Tp1, _Tp>
+ && experimental::is_convertible_v<_Ptr, element_type*>,
+ _Res>;
public:
- using element_type = typename _Base_type::element_type;
// 8.2.1.1, shared_ptr constructors
constexpr shared_ptr() noexcept = default;
- template<typename _Tp1>
- explicit shared_ptr(_Tp1* __p) : _Base_type(__p) { }
+ template<typename _Tp1, typename = _SafeConv<_Tp1>>
+ explicit
+ shared_ptr(_Tp1* __p) : _Base_type(__p) { }
- template<typename _Tp1, typename _Deleter>
+ template<typename _Tp1, typename _Deleter, typename = _SafeConv<_Tp1>>
shared_ptr(_Tp1* __p, _Deleter __d)
: _Base_type(__p, __d) { }
- template<typename _Tp1, typename _Deleter, typename _Alloc>
+ template<typename _Tp1, typename _Deleter, typename _Alloc,
+ typename = _SafeConv<_Tp1>>
shared_ptr(_Tp1* __p, _Deleter __d, _Alloc __a)
: _Base_type(__p, __d, __a) { }
shared_ptr(shared_ptr<_Tp1>&& __r) noexcept
: _Base_type(std::move(__r)) { }
- template<typename _Tp1>
- explicit shared_ptr(const weak_ptr<_Tp1>& __r)
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
+ explicit
+ shared_ptr(const weak_ptr<_Tp1>& __r)
: _Base_type(__r) { }
#if _GLIBCXX_USE_DEPRECATED
- template<typename _Tp1>
+ template<typename _Tp1, typename = _Compatible<_Tp1>>
shared_ptr(std::auto_ptr<_Tp1>&& __r)
- : _Base_type() { } // TODO
+ : _Base_type(std::move(__r)) { }
#endif
- template<typename _Tp1, typename _Del, typename
- = _Compatible<remove_pointer_t<
- typename unique_ptr<_Tp1, _Del>::pointer>>>
- shared_ptr(std::unique_ptr<_Tp1, _Del>&& __r)
+ template<typename _Tp1, typename _Del,
+ typename = _UniqCompatible<_Tp1, _Del>>
+ shared_ptr(unique_ptr<_Tp1, _Del>&& __r)
: _Base_type(std::move(__r)) { }
constexpr shared_ptr(nullptr_t __p)
#endif
template <typename _Tp1, typename _Del>
- _Compatible<_Tp1, shared_ptr&>
+ _UniqCompatible<_Tp1, _Del, shared_ptr&>
operator=(unique_ptr<_Tp1, _Del>&& __r)
{
_Base_type::operator=(std::move(__r));
private:
template<typename _Alloc, typename... _Args>
- shared_ptr(_Sp_make_shared_tag __tag, const _Alloc& __a,
- _Args&&... __args)
- : _Base_type(__tag, __a, std::forward<_Args>(__args)...)
- { }
+ shared_ptr(_Sp_make_shared_tag __tag, const _Alloc& __a,
+ _Args&&... __args)
+ : _Base_type(__tag, __a, std::forward<_Args>(__args)...)
+ { }
template<typename _Tp1, typename _Alloc, typename... _Args>
friend shared_ptr<_Tp1>
class weak_ptr : public __weak_ptr<_Tp>
{
template<typename _Tp1, typename _Res = void>
- using _Compatible
- = enable_if_t<__sp_compatible<_Tp1, _Tp>::value, _Res>;
+ using _Compatible = enable_if_t<__sp_compatible_v<_Tp1, _Tp>, _Res>;
using _Base_type = __weak_ptr<_Tp>;
shared_from_this() const
{ return shared_ptr<const _Tp>(this->_M_weak_this); }
+ weak_ptr<_Tp>
+ weak_from_this() noexcept
+ { return _M_weak_this; }
+
+ weak_ptr<const _Tp>
+ weak_from_this() const noexcept
+ { return _M_weak_this; }
+
private:
template<typename _Tp1>
void