Currently std::list uses raw pointers to connect its nodes, which is
non-conforming. We should use the allocator's pointer type everywhere
that a "pointer" is needed.
Because the existing types like _List_node<T> are part of the ABI now,
we can't change them. To support nodes that are connected by fancy
pointers we need a parallel hierarchy of node types. This change
introduces new class templates parameterized on the allocator's
void_pointer type, __list::_Node_base and __list::_Node_header, and new
class templates parameterized on the allocator's pointer type,
__list::Node, __list::_Iterator. The iterator class template is used for
both iterator and const_iterator. Whether std::list<T, A> should use the
old _List_node<T> or new _list::_Node<A::pointer> type family internally
is controlled by a new __list::_Node_traits traits template.
Because std::pointer_traits and std::__to_address are not defined for
C++98, there is no way to support fancy pointers in C++98. For C++98 the
_Node_traits traits always choose the old _List_node family.
In case anybody is currently using std::list with an allocator that has
a fancy pointer, this change would be an ABI break, because their
std::list instantiations would start to (correctly) use the fancy
pointer type. If the fancy pointer just contains a single pointer and so
has the same size, layout, and object represenation as a raw pointer,
the code might still work (despite being an ODR violation). But if their
fancy pointer has a different representation, they would need to
recompile all their code using that allocator with std::list. Because
std::list will never use fancy pointers in C++98 mode, recompiling
everything to use fancy pointers isn't even possible if mixing C++98 and
C++11 code that uses std::list. To alleviate this problem, compiling
with -D_GLIBCXX_LIST_USE_ALLOC_PTR=0 will force std::list to have the
old, non-conforming behaviour and use raw pointers internally. This
macro is currently undocumented, which needs to be fixed.
Pretty printers for std::list need to be updated to handle the new node
types.
libstdc++-v3/ChangeLog:
PR libstdc++/57272
PR libstdc++/110952
* include/bits/list.tcc (_List_base::_M_clear()): Replace uses
of raw pointers.
(list::emplace, list::insert): Likewise.
(list::sort): Adjust check for 0 or 1 wsize. Use template
argument list for _Scratch_list.
* include/bits/stl_list.h (_GLIBCXX_LIST_USE_ALLOC_PTR): Define.
(_List_node_base::_Base_ptr): New typedef.
(_List_node_base::_M_base): New member functions.
(_List_node_header::_M_base): Make public and add
using-declaration for base class overload.
(__list::_Node_traits, __list::_Node_base)
(__list::_Node_header, __list::_Node, __list::_Iterator): New
class templates.
(_Scratch_list): Turn class into class template. Use _Base_ptr
typedef instead of _List_node_base*.
(_List_node::_Node_ptr): New typedef.
(_List_node::_M_node_ptr): New member function.
(_List_base, _List_impl): Use _Node_traits to get node types.
(_List_base::_M_get_node, _List_base::_M_put_node): Convert
to/from _List_node<T>* if required.
(_List_base(_List_base&&, _Node_alloc_type&&)): Use if constexpr
to make function a no-op for fancy pointers.
(_List_base::_S_distance, _List_base::_M_distance)
(_List_base::_M_node_count): Likewise.
(list): Use _Node_traits to get iterator, node and pointer
types.
(list::_M_create_node): Use _Node_ptr typedef instead of _Node*.
(list::end, list::cend, list::empty): Use node header's
_M_base() function instead of taking its address.
(list::swap): Use _Node_traits to get node base type.
(list::_M_create_node, list::_M_insert, list::_M_erase): Use
_Node_ptr typedef instead of _Node*.
(__distance): Overload for __list::_Iterator.
(_Node_base::swap, _Node_base::_M_transfer): Define non-inline
member functions of class templates.
(_Node_header::_M_reverse): Likewise.
*
testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc:
New test.
*
testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc:
New test.
---
Tested x86_64-linux.
Pull request at https://forge.sourceware.org/gcc/gcc-TEST/pulls/25
libstdc++-v3/include/bits/list.tcc | 42 +-
libstdc++-v3/include/bits/stl_list.h | 552 ++++++++++++++++--
.../explicit_instantiation/alloc_ptr.cc | 76 +++
.../alloc_ptr_ignored.cc | 4 +
4 files changed, 608 insertions(+), 66 deletions(-)
create mode 100644
libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc
create mode 100644
libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc
diff --git a/libstdc++-v3/include/bits/list.tcc
b/libstdc++-v3/include/bits/list.tcc
index 65835c1379f..58892f78c8f 100644
--- a/libstdc++-v3/include/bits/list.tcc
+++ b/libstdc++-v3/include/bits/list.tcc
@@ -66,11 +66,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_List_base<_Tp, _Alloc>::
_M_clear() _GLIBCXX_NOEXCEPT
{
- typedef _List_node<_Tp> _Node;
- __detail::_List_node_base* __cur = _M_impl._M_node._M_next;
- while (__cur != &_M_impl._M_node)
+ typedef typename _Node_traits::_Node _Node;
+ typedef typename _Node::_Node_ptr _Node_ptr;
+ typename _Node::_Base_ptr __cur = _M_impl._M_node._M_next;
+ while (__cur != _M_impl._M_node._M_base())
{
- _Node* __tmp = static_cast<_Node*>(__cur);
+ _Node_ptr __tmp = static_cast<_Node&>(*__cur)._M_node_ptr();
__cur = __tmp->_M_next;
_Tp* __val = __tmp->_M_valptr();
#if __cplusplus >= 201103L
@@ -89,10 +90,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
list<_Tp, _Alloc>::
emplace(const_iterator __position, _Args&&... __args)
{
- _Node* __tmp = _M_create_node(std::forward<_Args>(__args)...);
+ _Node_ptr __tmp = _M_create_node(std::forward<_Args>(__args)...);
__tmp->_M_hook(__position._M_const_cast()._M_node);
this->_M_inc_size(1);
- return iterator(__tmp);
+ return iterator(__tmp->_M_base());
}
#endif
@@ -105,10 +106,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(iterator __position, const value_type& __x)
#endif
{
- _Node* __tmp = _M_create_node(__x);
+ _Node_ptr __tmp = _M_create_node(__x);
__tmp->_M_hook(__position._M_const_cast()._M_node);
this->_M_inc_size(1);
- return iterator(__tmp);
+ return iterator(__tmp->_M_base());
}
#if __cplusplus >= 201103L
@@ -482,10 +483,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
sort()
{
// Do nothing if the list has length 0 or 1.
- if (this->_M_impl._M_node._M_next != &this->_M_impl._M_node
- && this->_M_impl._M_node._M_next->_M_next != &this->_M_impl._M_node)
+ if (empty() || ++begin() == end())
+ return;
+
{
- using __detail::_Scratch_list;
+ typedef __list::_Scratch_list<typename _Node_traits::_Node_base>
+ _Scratch_list;
+
// The algorithm used here is largely unchanged from the SGI STL
// and is described in The C++ Standard Template Library by Plauger,
// Stepanov, Lee, Musser.
@@ -499,7 +503,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_Scratch_list* __fill = __tmp;
_Scratch_list* __counter;
- _Scratch_list::_Ptr_cmp<iterator, void> __ptr_comp;
+ typename _Scratch_list::template _Ptr_cmp<iterator, void> __ptr_comp;
__try
{
@@ -614,17 +618,21 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
sort(_StrictWeakOrdering __comp)
{
// Do nothing if the list has length 0 or 1.
- if (this->_M_impl._M_node._M_next != &this->_M_impl._M_node
- && this->_M_impl._M_node._M_next->_M_next != &this->_M_impl._M_node)
+ if (empty() || ++begin() == end())
+ return;
+
{
- using __detail::_Scratch_list;
+ typedef __list::_Scratch_list<typename _Node_traits::_Node_base>
+ _Scratch_list;
+
_Scratch_list __carry;
_Scratch_list __tmp[64];
_Scratch_list* __fill = __tmp;
_Scratch_list* __counter;
- _Scratch_list::_Ptr_cmp<iterator, _StrictWeakOrdering> __ptr_comp
- = { __comp };
+ typename _Scratch_list::
+ template _Ptr_cmp<iterator, _StrictWeakOrdering> __ptr_comp
+ = { __comp };
__try
{
diff --git a/libstdc++-v3/include/bits/stl_list.h
b/libstdc++-v3/include/bits/stl_list.h
index b1ab335ba4c..4628c782db6 100644
--- a/libstdc++-v3/include/bits/stl_list.h
+++ b/libstdc++-v3/include/bits/stl_list.h
@@ -62,6 +62,7 @@
#if __cplusplus >= 201103L
#include <initializer_list>
#include <bits/allocated_ptr.h>
+#include <bits/ptr_traits.h>
#include <ext/aligned_buffer.h>
#endif
#if __glibcxx_ranges_to_container // C++ >= 23
@@ -69,6 +70,13 @@
# include <bits/ranges_util.h> // ranges::subrange
#endif
+#if __cplusplus < 201103L
+#undef _GLIBCXX_LIST_USE_ALLOC_PTR
+#define _GLIBCXX_LIST_USE_ALLOC_PTR 0
+#elif ! defined _GLIBCXX_LIST_USE_ALLOC_PTR
+#define _GLIBCXX_LIST_USE_ALLOC_PTR 1
+#endif
+
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
@@ -84,6 +92,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
/// Common part of a node in the %list.
struct _List_node_base
{
+ typedef _List_node_base* _Base_ptr;
+
_List_node_base* _M_next;
_List_node_base* _M_prev;
@@ -102,6 +112,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
void
_M_unhook() _GLIBCXX_USE_NOEXCEPT;
+
+ _List_node_base* _M_base() { return this; }
+ const _List_node_base* _M_base() const { return this; }
};
struct _List_size
@@ -112,7 +125,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
#endif
};
-
/// The %list node header.
struct _List_node_header : public _List_node_base, _List_size
{
@@ -157,18 +169,302 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_List_size::operator=(_List_size());
}
- private:
- _List_node_base* _M_base() { return this; }
+ using _List_node_base::_M_base;
+#if ! _GLIBCXX_INLINE_VERSION
+ _List_node_base* _M_base() { return this; } // XXX GLIBCXX_ABI Deprecated
+#endif
};
- // Used by list::sort to hold nodes being sorted.
- struct _Scratch_list : _List_node_base
+ } // namespace detail
+
+_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
+ template<typename _Tp> struct _List_node;
+ template<typename _Tp> struct _List_iterator;
+ template<typename _Tp> struct _List_const_iterator;
+_GLIBCXX_BEGIN_NAMESPACE_CXX11
+ template<typename _Tp, typename _Allocator> class list;
+_GLIBCXX_END_NAMESPACE_CXX11
+_GLIBCXX_END_NAMESPACE_CONTAINER
+
+namespace __list
+{
+ // Determine the node and iterator types used by std::list.
+ template<typename _Tp, typename _Ptr>
+ struct _Node_traits;
+
+ // Specialization for the simple case where the allocator's pointer type
+ // is the same type as value_type*.
+ // For ABI compatibility we can't change the types used for this case.
+ template<typename _Tp>
+ struct _Node_traits<_Tp, _Tp*>
{
- _Scratch_list() { _M_next = _M_prev = this; }
+ typedef __detail::_List_node_base _Node_base;
+ typedef __detail::_List_node_header _Node_header;
+ typedef _GLIBCXX_STD_C::_List_node<_Tp> _Node;
+ typedef _GLIBCXX_STD_C::_List_iterator<_Tp> _Iterator;
+ typedef _GLIBCXX_STD_C::_List_const_iterator<_Tp> _Const_iterator;
+ };
- bool empty() const { return _M_next == this; }
+#if ! _GLIBCXX_LIST_USE_ALLOC_PTR
+ // Always use the T* specialization.
+ template<typename _Tp, typename _Ptr>
+ struct _Node_traits
+ : _Node_traits<_Tp, _Tp*>
+ { };
+#else
- void swap(_List_node_base& __l) { _List_node_base::swap(*this, __l); }
+ // The base class for a list node. Contains the pointers connecting nodes.
+ template<typename _VoidPtr>
+ struct _Node_base
+ {
+ using _Base_ptr = __ptr_rebind<_VoidPtr, _Node_base>;
+ _Base_ptr _M_next;
+ _Base_ptr _M_prev;
+
+ static void
+ swap(_Node_base& __x, _Node_base& __y) noexcept;
+
+ void
+ _M_transfer(_Base_ptr const __first, _Base_ptr const __last);
+
+ void
+ _M_hook(_Base_ptr const __position) noexcept
+ {
+ auto __self = pointer_traits<_Base_ptr>::pointer_to(*this);
+ this->_M_next = __position;
+ this->_M_prev = __position->_M_prev;
+ __position->_M_prev->_M_next = __self;
+ __position->_M_prev = __self;
+ }
+
+ void
+ _M_unhook() noexcept
+ {
+ auto const __next_node = this->_M_next;
+ auto const __prev_node = this->_M_prev;
+ __prev_node->_M_next = __next_node;
+ __next_node->_M_prev = __prev_node;
+ }
+
+ // This is not const-correct, but it's only used in a const access path
+ // by std::list::empty(), where it doesn't escape, and by
+ // std::list::end() const, where the pointer is used to initialize a
+ // const_iterator and so constness is restored.
+ _Base_ptr
+ _M_base() const noexcept
+ {
+ return pointer_traits<_Base_ptr>::
+ pointer_to(const_cast<_Node_base&>(*this));
+ }
+ };
+
+ using ::std::__detail::_List_size;
+
+ // The special sentinel node contained by a std::list.
+ // begin()->_M_node->_M_prev and end()->_M_node point to this header.
+ // This is not a complete node, as it doesn't contain a value.
+ template<typename _VoidPtr>
+ struct _Node_header
+ : public _Node_base<_VoidPtr>, _List_size
+ {
+ _Node_header() noexcept
+ { _M_init(); }
+
+ _Node_header(_Node_header&& __x) noexcept
+ : _Node_base<_VoidPtr>(__x), _List_size(__x)
+ {
+ if (__x._M_base()->_M_next == __x._M_base())
+ this->_M_next = this->_M_prev = this->_M_base();
+ else
+ {
+ this->_M_next->_M_prev = this->_M_prev->_M_next = this->_M_base();
+ __x._M_init();
+ }
+ }
+
+ void
+ _M_move_nodes(_Node_header&& __x) noexcept
+ {
+ auto const __xnode = __x._M_base();
+ if (__xnode->_M_next == __xnode)
+ _M_init();
+ else
+ {
+ auto const __node = this->_M_base();
+ __node->_M_next = __xnode->_M_next;
+ __node->_M_prev = __xnode->_M_prev;
+ __node->_M_next->_M_prev = __node->_M_prev->_M_next = __node;
+ _List_size::operator=(__x);
+ __x._M_init();
+ }
+ }
+
+ void
+ _M_init() noexcept
+ {
+ this->_M_next = this->_M_prev = this->_M_base();
+ _List_size::operator=(_List_size());
+ }
+
+ void _M_reverse() noexcept;
+ };
+
+ // The node type used for allocators with fancy pointers.
+ template<typename _ValPtr>
+ struct _Node : public __list::_Node_base<__ptr_rebind<_ValPtr, void>>
+ {
+ using value_type = typename pointer_traits<_ValPtr>::element_type;
+ using _Node_ptr = __ptr_rebind<_ValPtr, _Node>;
+
+ union {
+ value_type _M_data;
+ };
+
+ _Node() { }
+ ~_Node() { }
+ _Node(_Node&&) = delete;
+
+ value_type* _M_valptr() { return std::__addressof(_M_data); }
+ value_type const* _M_valptr() const { return std::__addressof(_M_data); }
+
+ _Node_ptr
+ _M_node_ptr()
+ { return pointer_traits<_Node_ptr>::pointer_to(*this); }
+ };
+
+ template<bool _Const, typename _Ptr> class _Iterator;
+
+ // Primary template used when the allocator uses fancy pointers.
+ template<typename _Tp, typename _Ptr>
+ struct _Node_traits
+ {
+ private:
+ using _VoidPtr = __ptr_rebind<_Ptr, void>;
+ using _ValPtr = __ptr_rebind<_Ptr, _Tp>;
+
+ public:
+ using _Node_base = __list::_Node_base<_VoidPtr>;
+ using _Node_header = __list::_Node_header<_VoidPtr>;
+ using _Node = __list::_Node<_ValPtr>;
+ using _Iterator = __list::_Iterator<false, _ValPtr>;
+ using _Const_iterator = __list::_Iterator<true, _ValPtr>;
+ };
+
+ template<bool _Const, typename _Ptr>
+ class _Iterator
+ {
+ using _Node = __list::_Node<_Ptr>;
+ using _Base_ptr = typename _Node::_Base_ptr;
+
+ template<typename _Tp>
+ using __maybe_const = __conditional_t<_Const, const _Tp, _Tp>;
+
+ public:
+ using value_type = typename pointer_traits<_Ptr>::element_type;
+ using difference_type = ptrdiff_t;
+ using iterator_category = bidirectional_iterator_tag;
+ using pointer = __maybe_const<value_type>*;
+ using reference = __maybe_const<value_type>&;
+
+ constexpr _Iterator() noexcept : _M_node() { }
+
+ _Iterator(const _Iterator&) = default;
+ _Iterator& operator=(const _Iterator&) = default;
+
+#ifdef __glibcxx_concepts
+ constexpr
+ _Iterator(const _Iterator<false, _Ptr>& __i) requires _Const
+#else
+ template<bool _OtherConst,
+ typename = __enable_if_t<_Const && !_OtherConst>>
+ _Iterator(const _Iterator<_OtherConst, _Ptr>& __i)
+#endif
+ : _M_node(__i._M_node) { }
+
+ constexpr explicit
+ _Iterator(_Base_ptr __x) noexcept
+ : _M_node(__x) { }
+
+ // Must downcast from _Node_base to _Node to get to value.
+ [[__nodiscard__]]
+ constexpr reference
+ operator*() const noexcept
+ { return static_cast<_Node&>(*_M_node)._M_data; }
+
+ [[__nodiscard__]]
+ constexpr pointer
+ operator->() const noexcept
+ { return std::__addressof(operator*()); }
+
+ _GLIBCXX14_CONSTEXPR _Iterator&
+ operator++() noexcept
+ {
+ _M_node = _M_node->_M_next;
+ return *this;
+ }
+
+ _GLIBCXX14_CONSTEXPR _Iterator
+ operator++(int) noexcept
+ {
+ auto __tmp = *this;
+ _M_node = _M_node->_M_next;
+ return __tmp;
+ }
+
+ _GLIBCXX14_CONSTEXPR _Iterator&
+ operator--() noexcept
+ {
+ _M_node = _M_node->_M_prev;
+ return *this;
+ }
+
+ _GLIBCXX14_CONSTEXPR _Iterator
+ operator--(int) noexcept
+ {
+ auto __tmp = *this;
+ _M_node = _M_node->_M_prev;
+ return __tmp;
+ }
+
+ [[__nodiscard__]]
+ friend constexpr bool
+ operator==(const _Iterator& __x, const _Iterator& __y) noexcept
+ { return __x._M_node == __y._M_node; }
+
+#if __cpp_impl_three_way_comparison < 201907L
+ [[__nodiscard__]]
+ friend constexpr bool
+ operator!=(const _Iterator& __x, const _Iterator& __y) noexcept
+ { return __x._M_node != __y._M_node; }
+#endif
+
+ private:
+ template<typename _Tp, typename _Allocator>
+ friend class _GLIBCXX_STD_C::list;
+
+ constexpr _Iterator<false, _Ptr>
+ _M_const_cast() const noexcept
+ { return _Iterator<false, _Ptr>(_M_node); }
+
+ friend _Iterator<!_Const, _Ptr>;
+
+ _Base_ptr _M_node;
+ };
+#endif // LIST_USE_ALLOC_PTR
+
+ // Used by std::list::sort to hold nodes being sorted.
+ template<typename _NodeBaseT>
+ struct _Scratch_list
+ : _NodeBaseT
+ {
+ typedef _NodeBaseT _Base;
+ typedef typename _Base::_Base_ptr _Base_ptr;
+
+ _Scratch_list() { this->_M_next = this->_M_prev = this->_M_base(); }
+
+ bool empty() const { return this->_M_next == this->_M_base(); }
+
+ void swap(_Base& __l) { _Base::swap(*this, __l); }
template<typename _Iter, typename _Cmp>
struct _Ptr_cmp
@@ -176,8 +472,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_Cmp _M_cmp;
bool
- operator()(__detail::_List_node_base* __lhs,
- __detail::_List_node_base* __rhs) /* not const */
+ operator()(_Base_ptr __lhs, _Base_ptr __rhs) /* not const */
{ return _M_cmp(*_Iter(__lhs), *_Iter(__rhs)); }
};
@@ -185,26 +480,25 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
struct _Ptr_cmp<_Iter, void>
{
bool
- operator()(__detail::_List_node_base* __lhs,
- __detail::_List_node_base* __rhs) const
+ operator()(_Base_ptr __lhs, _Base_ptr __rhs) const
{ return *_Iter(__lhs) < *_Iter(__rhs); }
};
// Merge nodes from __x into *this. Both lists must be sorted wrt _Cmp.
template<typename _Cmp>
void
- merge(_List_node_base& __x, _Cmp __comp)
+ merge(_Base& __x, _Cmp __comp)
{
- _List_node_base* __first1 = _M_next;
- _List_node_base* const __last1 = this;
- _List_node_base* __first2 = __x._M_next;
- _List_node_base* const __last2 = std::__addressof(__x);
+ _Base_ptr __first1 = this->_M_next;
+ _Base_ptr const __last1 = this->_M_base();
+ _Base_ptr __first2 = __x._M_next;
+ _Base_ptr const __last2 = __x._M_base();
while (__first1 != __last1 && __first2 != __last2)
{
if (__comp(__first2, __first1))
{
- _List_node_base* __next = __first2->_M_next;
+ _Base_ptr __next = __first2->_M_next;
__first1->_M_transfer(__first2, __next);
__first2 = __next;
}
@@ -216,18 +510,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
// Splice the node at __i into *this.
- void _M_take_one(_List_node_base* __i)
+ void _M_take_one(_Base_ptr __i)
{ this->_M_transfer(__i, __i->_M_next); }
// Splice all nodes from *this after __i.
- void _M_put_all(_List_node_base* __i)
+ void _M_put_all(_Base_ptr __i)
{
if (!empty())
- __i->_M_transfer(_M_next, this);
+ __i->_M_transfer(this->_M_next, this->_M_base());
}
};
- } // namespace detail
+} // namespace __list
+
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
@@ -235,6 +530,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
template<typename _Tp>
struct _List_node : public __detail::_List_node_base
{
+ typedef _List_node* _Node_ptr;
+
#if __cplusplus >= 201103L
__gnu_cxx::__aligned_membuf<_Tp> _M_storage;
_Tp* _M_valptr() { return _M_storage._M_ptr(); }
@@ -244,6 +541,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_Tp* _M_valptr() { return std::__addressof(_M_data); }
_Tp const* _M_valptr() const { return std::__addressof(_M_data); }
#endif
+
+ _Node_ptr _M_node_ptr() { return this; }
};
/**
@@ -432,14 +731,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
rebind<_Tp>::other _Tp_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type>
_Tp_alloc_traits;
+
+ typedef __list::_Node_traits<_Tp, typename _Tp_alloc_traits::pointer>
+ _Node_traits;
typedef typename _Tp_alloc_traits::template
- rebind<_List_node<_Tp> >::other _Node_alloc_type;
+ rebind<typename _Node_traits::_Node>::other _Node_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Node_alloc_type> _Node_alloc_traits;
struct _List_impl
: public _Node_alloc_type
{
- __detail::_List_node_header _M_node;
+ typename _Node_traits::_Node_header _M_node;
_List_impl() _GLIBCXX_NOEXCEPT_IF(
is_nothrow_default_constructible<_Node_alloc_type>::value)
@@ -481,6 +783,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
void _M_dec_size(size_t) { }
#endif
+#if __cplusplus < 201103L || _GLIBCXX_LIST_USE_ALLOC_PTR
typename _Node_alloc_traits::pointer
_M_get_node()
{ return _Node_alloc_traits::allocate(_M_impl, 1); }
@@ -488,6 +791,22 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
void
_M_put_node(typename _Node_alloc_traits::pointer __p) _GLIBCXX_NOEXCEPT
{ _Node_alloc_traits::deallocate(_M_impl, __p, 1); }
+#else
+ // When not using the allocator's pointer type internally we must
+ // convert between _Node_ptr (i.e. _List_node*) and the allocator's
+ // pointer type. We do that here.
+ _List_node<_Tp>*
+ _M_get_node()
+ { return std::__to_address(_Node_alloc_traits::allocate(_M_impl, 1)); }
+
+ void
+ _M_put_node(_List_node<_Tp>* __p)
+ {
+ using __alloc_pointer = typename _Node_alloc_traits::pointer;
+ auto __ap = pointer_traits<__alloc_pointer>::pointer_to(*__p);
+ _Node_alloc_traits::deallocate(_M_impl, __ap, 1);
+ }
+#endif
public:
typedef _Alloc allocator_type;
@@ -547,13 +866,24 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
// so that explicit instantiation declarations of std::list that were
// compiled with old versions of GCC can still find these old symbols.
+ // Use 'if constexpr' so that the functions don't do anything for
+ // specializations using _Node_traits<T, fancy-pointer>, because any
+ // old code referencing these symbols wasn't using the fancy-pointer
+ // specializations.
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
+
# if __cplusplus >= 201103L
_List_base(_List_base&& __x, _Node_alloc_type&& __a)
: _M_impl(std::move(__a))
{
- if (__x._M_get_Node_allocator() == _M_get_Node_allocator())
- _M_move_nodes(std::move(__x));
- // else caller must move individual elements.
+#if _GLIBCXX_LIST_USE_ALLOC_PTR
+ if constexpr (is_same<typename _Tp_alloc_traits::pointer, _Tp*>::value)
+#endif
+ if (__x._M_get_Node_allocator() == _M_get_Node_allocator())
+ _M_move_nodes(std::move(__x));
+ // else caller must move individual elements.
}
# endif
@@ -561,13 +891,20 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
_S_distance(const __detail::_List_node_base* __first,
const __detail::_List_node_base* __last)
{
- size_t __n = 0;
- while (__first != __last)
+#if _GLIBCXX_LIST_USE_ALLOC_PTR
+ if constexpr (!is_same<typename _Tp_alloc_traits::pointer, _Tp*>::value)
+ return 0;
+ else
+#endif
{
- __first = __first->_M_next;
- ++__n;
+ size_t __n = 0;
+ while (__first != __last)
+ {
+ __first = __first->_M_next;
+ ++__n;
+ }
+ return __n;
}
- return __n;
}
#if _GLIBCXX_USE_CXX11_ABI
@@ -584,10 +921,16 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
// count the number of nodes
size_t _M_node_count() const
{
- return _S_distance(_M_impl._M_node._M_next,
- std::__addressof(_M_impl._M_node));
+#if _GLIBCXX_LIST_USE_ALLOC_PTR
+ if constexpr (!is_same<typename _Tp_alloc_traits::pointer, _Tp*>::value)
+ return 0;
+ else
+#endif
+ return _S_distance(_M_impl._M_node._M_next,
+ _M_impl._M_node._M_base());
}
#endif
+#pragma GCC diagnostic pop
#endif // ! INLINE_VERSION
};
@@ -663,6 +1006,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
typedef typename _Base::_Tp_alloc_traits _Tp_alloc_traits;
typedef typename _Base::_Node_alloc_type _Node_alloc_type;
typedef typename _Base::_Node_alloc_traits _Node_alloc_traits;
+ typedef typename _Base::_Node_traits _Node_traits;
public:
typedef _Tp value_type;
@@ -670,8 +1014,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
typedef typename _Tp_alloc_traits::const_pointer const_pointer;
typedef typename _Tp_alloc_traits::reference reference;
typedef typename _Tp_alloc_traits::const_reference const_reference;
- typedef _List_iterator<_Tp> iterator;
- typedef _List_const_iterator<_Tp> const_iterator;
+ typedef typename _Node_traits::_Iterator iterator;
+ typedef typename _Node_traits::_Const_iterator const_iterator;
typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
typedef std::reverse_iterator<iterator> reverse_iterator;
typedef size_t size_type;
@@ -681,7 +1025,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
protected:
// Note that pointers-to-_Node's can be ctor-converted to
// iterator types.
- typedef _List_node<_Tp> _Node;
+ typedef typename _Node_traits::_Node _Node;
+ typedef typename _Node::_Node_ptr _Node_ptr;
using _Base::_M_impl;
using _Base::_M_put_node;
@@ -695,10 +1040,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
* @a __args in it.
*/
#if __cplusplus < 201103L
- _Node*
+ _Node_ptr
_M_create_node(const value_type& __x)
{
- _Node* __p = this->_M_get_node();
+ _Node_ptr __p = this->_M_get_node();
__try
{
_Tp_alloc_type __alloc(_M_get_Node_allocator());
@@ -713,7 +1058,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
}
#else
template<typename... _Args>
- _Node*
+ _Node_ptr
_M_create_node(_Args&&... __args)
{
auto __p = this->_M_get_node();
@@ -1070,7 +1415,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
_GLIBCXX_NODISCARD
iterator
end() _GLIBCXX_NOEXCEPT
- { return iterator(&this->_M_impl._M_node); }
+ { return iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read-only (constant) iterator that points one past
@@ -1080,7 +1425,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
_GLIBCXX_NODISCARD
const_iterator
end() const _GLIBCXX_NOEXCEPT
- { return const_iterator(&this->_M_impl._M_node); }
+ { return const_iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read/write reverse iterator that points to the last
@@ -1141,7 +1486,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
[[__nodiscard__]]
const_iterator
cend() const noexcept
- { return const_iterator(&this->_M_impl._M_node); }
+ { return const_iterator(this->_M_impl._M_node._M_base()); }
/**
* Returns a read-only (constant) reverse iterator that points to
@@ -1171,7 +1516,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
*/
_GLIBCXX_NODISCARD bool
empty() const _GLIBCXX_NOEXCEPT
- { return this->_M_impl._M_node._M_next == &this->_M_impl._M_node; }
+ {
+ return this->_M_impl._M_node._M_next == this->_M_impl._M_node._M_base();
+ }
/** Returns the number of elements in the %list. */
_GLIBCXX_NODISCARD
@@ -1682,8 +2029,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
void
swap(list& __x) _GLIBCXX_NOEXCEPT
{
- __detail::_List_node_base::swap(this->_M_impl._M_node,
- __x._M_impl._M_node);
+ _Node_traits::_Node_base::swap(this->_M_impl._M_node,
+ __x._M_impl._M_node);
size_t __xsize = __x._M_get_size();
__x._M_set_size(this->_M_get_size());
@@ -2105,7 +2452,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
void
_M_insert(iterator __position, const value_type& __x)
{
- _Node* __tmp = _M_create_node(__x);
+ _Node_ptr __tmp = _M_create_node(__x);
__tmp->_M_hook(__position._M_node);
this->_M_inc_size(1);
}
@@ -2114,7 +2461,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
void
_M_insert(iterator __position, _Args&&... __args)
{
- _Node* __tmp = _M_create_node(std::forward<_Args>(__args)...);
+ _Node_ptr __tmp = _M_create_node(std::forward<_Args>(__args)...);
__tmp->_M_hook(__position._M_node);
this->_M_inc_size(1);
}
@@ -2126,7 +2473,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
{
this->_M_dec_size(1);
__position._M_node->_M_unhook();
- _Node* __n = static_cast<_Node*>(__position._M_node);
+ _Node_ptr __n = static_cast<_Node&>(*__position._M_node)._M_node_ptr();
#if __cplusplus >= 201103L
_Node_alloc_traits::destroy(_M_get_Node_allocator(), __n->_M_valptr());
#else
@@ -2397,6 +2744,113 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
}
return __n;
}
+
+#if _GLIBCXX_LIST_USE_ALLOC_PTR
+ template<bool _Const, typename _Ptr>
+ inline ptrdiff_t
+ __distance(__list::_Iterator<_Const, _Ptr> __first,
+ __list::_Iterator<_Const, _Ptr> __last,
+ input_iterator_tag __tag)
+ {
+ using _Tp = typename __list::_Iterator<_Const, _Ptr>::value_type;
+ using _Sentinel = typename __list::_Node_traits<_Tp, _Ptr>::_Node_header;
+ auto __beyond = __last;
+ ++__beyond;
+ const bool __whole = __first == __beyond;
+ if (__builtin_constant_p (__whole) && __whole)
+ return static_cast<const _Sentinel&>(*__last._M_node)._M_size;
+
+ ptrdiff_t __n = 0;
+ while (__first != __last)
+ {
+ ++__first;
+ ++__n;
+ }
+ return __n;
+ }
+#endif
+#endif
+
+#if _GLIBCXX_LIST_USE_ALLOC_PTR
+namespace __list
+{
+ template<typename _VoidPtr>
+ void
+ _Node_base<_VoidPtr>::swap(_Node_base& __x, _Node_base& __y) noexcept
+ {
+ auto __px = pointer_traits<_Base_ptr>::pointer_to(__x);
+ auto __py = pointer_traits<_Base_ptr>::pointer_to(__y);
+
+ if (__x._M_next != __px)
+ {
+ if (__y._M_next != __py)
+ {
+ using std::swap;
+ // Both __x and __y are not empty.
+ swap(__x._M_next,__y._M_next);
+ swap(__x._M_prev,__y._M_prev);
+ __x._M_next->_M_prev = __x._M_prev->_M_next = __px;
+ __y._M_next->_M_prev = __y._M_prev->_M_next = __py;
+ }
+ else
+ {
+ // __x is not empty, __y is empty.
+ __y._M_next = __x._M_next;
+ __y._M_prev = __x._M_prev;
+ __y._M_next->_M_prev = __y._M_prev->_M_next = __py;
+ __x._M_next = __x._M_prev = __px;
+ }
+ }
+ else if (__y._M_next != __py)
+ {
+ // __x is empty, __y is not empty.
+ __x._M_next = __y._M_next;
+ __x._M_prev = __y._M_prev;
+ __x._M_next->_M_prev = __x._M_prev->_M_next = __px;
+ __y._M_next = __y._M_prev = __py;
+ }
+ }
+
+ template<typename _VoidPtr>
+ void
+ _Node_base<_VoidPtr>::_M_transfer(_Base_ptr const __first,
+ _Base_ptr const __last)
+ {
+ __glibcxx_assert(__first != __last);
+
+ auto __self = pointer_traits<_Base_ptr>::pointer_to(*this);
+ if (__self != __last)
+ {
+ // Remove [first, last) from its old position.
+ __last->_M_prev->_M_next = __self;
+ __first->_M_prev->_M_next = __last;
+ this->_M_prev->_M_next = __first;
+
+ // Splice [first, last) into its new position.
+ auto const __tmp = this->_M_prev;
+ this->_M_prev = __last->_M_prev;
+ __last->_M_prev = __first->_M_prev;
+ __first->_M_prev = __tmp;
+ }
+ }
+
+ template<typename _VoidPtr>
+ void
+ _Node_header<_VoidPtr>::_M_reverse() noexcept
+ {
+ const auto __self = this->_M_base();
+ auto __tmp = __self;
+ do
+ {
+ using std::swap;
+ swap(__tmp->_M_next, __tmp->_M_prev);
+
+ // Old next node is now prev.
+ __tmp = __tmp->_M_prev;
+ }
+ while (__tmp != __self);
+ }
+} // namespace __list
#endif
_GLIBCXX_END_NAMESPACE_VERSION
diff --git
a/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc
b/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc
new file mode 100644
index 00000000000..01715b599a9
--- /dev/null
+++
b/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc
@@ -0,0 +1,76 @@
+// { dg-do compile { target c++11 } }
+
+#include <list>
+#include <testsuite_allocator.h>
+
+// An allocator that uses __gnu_cxx::_Pointer_adapter as its pointer type.
+template class std::list<int, __gnu_test::CustomPointerAlloc<int>>;
+
+// Unlike __gnu_cxx::_Pointer_adapter, this fancy pointer supports neither
+// implicit nor explicit conversions from raw pointers. The constructor from
+// a raw pointer is explicit and requires a second parameter. The only way for
+// containers to construct one of these pointers is pointer_traits::pointer_to.
+template<typename T>
+struct Pointer : __gnu_test::PointerBase<Pointer<T>, T>
+{
+ using Base = __gnu_test::PointerBase<Pointer<T>, T>;
+
+ Pointer() = default;
+ Pointer(std::nullptr_t) : Base() { }
+ explicit Pointer(T* p, int) : Base(p) { }
+
+ // Allow conversions to const_pointer and to void_pointer
+ template<typename U, typename = typename std::enable_if<
+ (!std::is_const<U>::value && std::is_same<T, const U>::value)
+ || (std::is_void<T>::value && std::is_convertible<U*, T*>::value)
+ >::type>
+ Pointer(const Pointer<U>& p) : Base(p.operator->()) { }
+
+ template<typename U>
+ static typename std::enable_if<std::is_same<U, T>::value, Pointer>::type
+ pointer_to(U& t)
+ { return Pointer(std::addressof(t), 1); }
+};
+
+// A minimal allocator that uses Pointer as its pointer type.
+template<typename T>
+struct Allocator
+{
+ using value_type = T;
+ using pointer = Pointer<T>;
+
+ Allocator() = default;
+ template<typename U>
+ Allocator(const Allocator<U>&) { }
+
+ pointer allocate(std::size_t n)
+ { return pointer(std::allocator<T>().allocate(n), 1); }
+
+ void deallocate(pointer p, std::size_t n)
+ {
+ std::allocator<T>().deallocate(p.operator->(), n);
+ }
+
+ bool operator==(const Allocator&) const { return true; }
+ bool operator!=(const Allocator&) const { return false; }
+};
+
+template class std::list<int, Allocator<int>>;
+
+#include <testsuite_iterators.h>
+
+void
+test_template_members(__gnu_test::input_container<short>& c)
+{
+ // Use member functions that are not included in explicit instantiations.
+ std::list<int, Allocator<int>> l(c.begin(), c.end());
+ l.assign(c.begin(), c.end());
+ l.emplace_front(1);
+ l.emplace_back(1);
+ l.emplace(l.begin(), 1);
+ l.remove_if([](int) { return false; });
+ l.unique([](int, int) { return false; });
+ l.merge(l, [](int, int) { return false; });
+ l.merge(std::move(l), [](int, int) { return false; });
+ l.sort([](int, int) { return false; });
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc
b/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc
new file mode 100644
index 00000000000..e6a499d2716
--- /dev/null
+++
b/libstdc++-v3/testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc
@@ -0,0 +1,4 @@
+// { dg-options "-D_GLIBCXX_LIST_USE_ALLOC_PTR=0" }
+// { dg-do compile { target c++11 } }
+
+#include "alloc_ptr.cc"
--
2.47.0
