https://gcc.gnu.org/g:69ce8e406a2aa0aba5dcae5e419503ec105355b0
commit r11-11567-g69ce8e406a2aa0aba5dcae5e419503ec105355b0
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Thu Mar 21 13:25:15 2024 +0000
libstdc++: Destroy allocators in re-inserted container nodes [PR114401]
The allocator objects in container node handles were not being destroyed
after the node was re-inserted into a container. They are stored in a
union and so need to be explicitly destroyed when the node becomes
empty. The containers were zeroing the node handle's pointer, which
makes it empty, causing the handle's destructor to think there's nothing
to clean up.
Add a new member function to the node handle which destroys the
allocator and zeros the pointer. Change the containers to call that
instead of just changing the pointer manually.
We can also remove the _M_empty member of the union which is not
necessary.
libstdc++-v3/ChangeLog:
PR libstdc++/114401
* include/bits/hashtable.h (_Hashtable::_M_reinsert_node): Call
release() on node handle instead of just zeroing its pointer.
(_Hashtable::_M_reinsert_node_multi): Likewise.
(_Hashtable::_M_merge_unique): Likewise.
* include/bits/node_handle.h (_Node_handle_common::release()):
New member function.
(_Node_handle_common::_Optional_alloc::_M_empty): Remove
unnecessary union member.
(_Node_handle_common): Declare _Hashtable as a friend.
* include/bits/stl_tree.h (_Rb_tree::_M_reinsert_node_unique):
Call release() on node handle instead of just zeroing its
pointer.
(_Rb_tree::_M_reinsert_node_equal): Likewise.
(_Rb_tree::_M_reinsert_node_hint_unique): Likewise.
(_Rb_tree::_M_reinsert_node_hint_equal): Likewise.
* testsuite/23_containers/multiset/modifiers/114401.cc: New test.
* testsuite/23_containers/set/modifiers/114401.cc: New test.
* testsuite/23_containers/unordered_multiset/modifiers/114401.cc:
New test.
* testsuite/23_containers/unordered_set/modifiers/114401.cc: New
test.
(cherry picked from commit c2e28df90a1640cebadef6c6c8ab5ea964071bb1)
Diff:
---
libstdc++-v3/include/bits/hashtable.h | 8 +-
libstdc++-v3/include/bits/node_handle.h | 19 +++-
libstdc++-v3/include/bits/stl_tree.h | 10 +-
.../23_containers/multiset/modifiers/114401.cc | 125 ++++++++++++++++++++
.../23_containers/set/modifiers/114401.cc | 125 ++++++++++++++++++++
.../unordered_multiset/modifiers/114401.cc | 126 +++++++++++++++++++++
.../unordered_set/modifiers/114401.cc | 126 +++++++++++++++++++++
7 files changed, 527 insertions(+), 12 deletions(-)
diff --git a/libstdc++-v3/include/bits/hashtable.h
b/libstdc++-v3/include/bits/hashtable.h
index eeefa7859226..ad0d6731de0a 100644
--- a/libstdc++-v3/include/bits/hashtable.h
+++ b/libstdc++-v3/include/bits/hashtable.h
@@ -950,7 +950,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// DR 1189.
// reserve, if present, comes from _Rehash_base.
-#if __cplusplus > 201402L
+#if __cplusplus > 201404L
/// Re-insert an extracted node into a container with unique keys.
insert_return_type
_M_reinsert_node(node_type&& __nh)
@@ -975,7 +975,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{
__ret.position
= _M_insert_unique_node(__bkt, __code, __nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
__ret.inserted = true;
}
}
@@ -995,7 +995,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
auto __code = this->_M_hash_code(__k);
auto __ret
= _M_insert_multi_node(__hint._M_cur, __code, __nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
return __ret;
}
@@ -1062,7 +1062,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{
auto __nh = __src.extract(__pos);
_M_insert_unique_node(__bkt, __code, __nh._M_ptr, __n_elt);
- __nh._M_ptr = nullptr;
+ __nh.release();
__n_elt = 1;
}
else if (__n_elt != 1)
diff --git a/libstdc++-v3/include/bits/node_handle.h
b/libstdc++-v3/include/bits/node_handle.h
index 7d8d0dc8cea8..8f500c2f8303 100644
--- a/libstdc++-v3/include/bits/node_handle.h
+++ b/libstdc++-v3/include/bits/node_handle.h
@@ -168,6 +168,16 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_ptr = nullptr;
}
+ // Destroys the allocator. Does not deallocate or destroy the node.
+ // Precondition: !empty()
+ // Postcondition: empty()
+ void
+ release() noexcept
+ {
+ _M_alloc.release();
+ _M_ptr = nullptr;
+ }
+
protected:
typename _AllocTraits::pointer _M_ptr;
@@ -219,9 +229,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
return __tmp;
}
- struct _Empty { };
-
- [[__no_unique_address__]] _Empty _M_empty;
[[__no_unique_address__]] _NodeAlloc _M_alloc;
};
@@ -231,6 +238,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
typename _Compare, typename _ValueAlloc>
friend class _Rb_tree;
+ template<typename _Key2, typename _Value2, typename _ValueAlloc,
+ typename _ExtractKey, typename _Equal,
+ typename _Hash, typename _RangeHash, typename _Unused,
+ typename _RehashPolicy, typename _Traits>
+ friend class _Hashtable;
+
/// @endcond
};
diff --git a/libstdc++-v3/include/bits/stl_tree.h
b/libstdc++-v3/include/bits/stl_tree.h
index ca7a663aaef3..3aa2c766362d 100644
--- a/libstdc++-v3/include/bits/stl_tree.h
+++ b/libstdc++-v3/include/bits/stl_tree.h
@@ -1434,7 +1434,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_move_assign(_Rb_tree&, false_type);
#endif
-#if __cplusplus > 201402L
+#if __cplusplus > 201404L
public:
/// Re-insert an extracted node.
insert_return_type
@@ -1452,7 +1452,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{
__ret.position
= _M_insert_node(__res.first, __res.second, __nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
__ret.inserted = true;
}
else
@@ -1480,7 +1480,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
__ret = _M_insert_node(__res.first, __res.second, __nh._M_ptr);
else
__ret = _M_insert_equal_lower_node(__nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
}
return __ret;
}
@@ -1499,7 +1499,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
if (__res.second)
{
__ret = _M_insert_node(__res.first, __res.second, __nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
}
else
__ret = iterator(__res.first);
@@ -1522,7 +1522,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
__ret = _M_insert_node(__res.first, __res.second, __nh._M_ptr);
else
__ret = _M_insert_equal_lower_node(__nh._M_ptr);
- __nh._M_ptr = nullptr;
+ __nh.release();
}
return __ret;
}
diff --git a/libstdc++-v3/testsuite/23_containers/multiset/modifiers/114401.cc
b/libstdc++-v3/testsuite/23_containers/multiset/modifiers/114401.cc
new file mode 100644
index 000000000000..630e18e287c6
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/multiset/modifiers/114401.cc
@@ -0,0 +1,125 @@
+// { dg-do run { target c++17 } }
+
+// PR libstdc++/114401 allocator destructor omitted when reinserting
node_handle
+
+#include <set>
+#include <memory>
+#include <testsuite_hooks.h>
+
+template<typename T>
+struct Alloc
+{
+ using value_type = T;
+ using propagate_on_container_copy_assignment = std::true_type;
+ using propagate_on_container_move_assignment = std::true_type;
+ using propagate_on_container_swap = std::true_type;
+
+ Alloc(int identity) : id(std::make_shared<int>(identity)) { }
+
+ template<typename U>
+ Alloc(const Alloc<U> a) : id(a.id) { }
+
+ T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
+ void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n);
}
+
+ template<typename U>
+ friend bool
+ operator==(const Alloc& a, const Alloc<U>& a2)
+ { return a.id == a2.id; }
+
+ template<typename U>
+ friend bool
+ operator!=(const Alloc& a, const Alloc<U>& a2)
+ { return !(a == a2); }
+
+ std::shared_ptr<int> id;
+};
+
+using test_type = std::multiset<int, std::less<int>, Alloc<int>>;
+
+void
+test_node_ops()
+{
+ test_type s1({1,3,5}, Alloc<int>(1));
+ test_type s2({2,4,6,8}, Alloc<int>(2));
+ VERIFY( s1.get_allocator() != s2.get_allocator() );
+
+ auto node_a = s1.extract(1);
+ VERIFY( ! node_a.empty() );
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+
+ node_a = std::move(node_a); // self-move
+ VERIFY( node_a.empty() );
+
+ swap(node_a, node_a); // self-swap
+ VERIFY( node_a.empty() );
+
+ auto node_b = s2.extract(2);
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ node_a = std::move(node_b); // empty = !empty
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(!empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ node_a = s1.extract(3); // !empty = !empty
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+ node_b = s2.extract(0); // empty = empty
+ VERIFY( node_b.empty() );
+ node_b = s2.extract(6); // empty = !empty
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(!empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.get_allocator() == s1.get_allocator() );
+
+ node_a = {};
+ node_b = std::move(node_a); // !empty = empty
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+}
+
+void
+test_alloc_lifetime()
+{
+ Alloc<int> a(1);
+ test_type s({1,2,3}, a);
+ VERIFY( a.id.use_count() == 2 ); // a and the copy in s
+
+ s.insert(s.extract(1));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(s.begin(), s.extract(2));
+ VERIFY( a.id.use_count() == 2 );
+
+ auto node = s.extract(1);
+ VERIFY( a.id.use_count() == 3 );
+ node = s.extract(0);
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(std::move(node));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type(s));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type({4,5,6}, a));
+ VERIFY( a.id.use_count() == 2 );
+}
+
+int main()
+{
+ test_node_ops();
+ test_alloc_lifetime();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/set/modifiers/114401.cc
b/libstdc++-v3/testsuite/23_containers/set/modifiers/114401.cc
new file mode 100644
index 000000000000..f0a06a8c1a28
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/set/modifiers/114401.cc
@@ -0,0 +1,125 @@
+// { dg-do run { target c++17 } }
+
+// PR libstdc++/114401 allocator destructor omitted when reinserting
node_handle
+
+#include <set>
+#include <memory>
+#include <testsuite_hooks.h>
+
+template<typename T>
+struct Alloc
+{
+ using value_type = T;
+ using propagate_on_container_copy_assignment = std::true_type;
+ using propagate_on_container_move_assignment = std::true_type;
+ using propagate_on_container_swap = std::true_type;
+
+ Alloc(int identity) : id(std::make_shared<int>(identity)) { }
+
+ template<typename U>
+ Alloc(const Alloc<U> a) : id(a.id) { }
+
+ T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
+ void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n);
}
+
+ template<typename U>
+ friend bool
+ operator==(const Alloc& a, const Alloc<U>& a2)
+ { return a.id == a2.id; }
+
+ template<typename U>
+ friend bool
+ operator!=(const Alloc& a, const Alloc<U>& a2)
+ { return !(a == a2); }
+
+ std::shared_ptr<int> id;
+};
+
+using test_type = std::set<int, std::less<int>, Alloc<int>>;
+
+void
+test_node_ops()
+{
+ test_type s1({1,3,5}, Alloc<int>(1));
+ test_type s2({2,4,6,8}, Alloc<int>(2));
+ VERIFY( s1.get_allocator() != s2.get_allocator() );
+
+ auto node_a = s1.extract(1);
+ VERIFY( ! node_a.empty() );
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+
+ node_a = std::move(node_a); // self-move
+ VERIFY( node_a.empty() );
+
+ swap(node_a, node_a); // self-swap
+ VERIFY( node_a.empty() );
+
+ auto node_b = s2.extract(2);
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ node_a = std::move(node_b); // empty = !empty
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(!empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ node_a = s1.extract(3); // !empty = !empty
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+ node_b = s2.extract(0); // empty = empty
+ VERIFY( node_b.empty() );
+ node_b = s2.extract(6); // empty = !empty
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(!empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.get_allocator() == s1.get_allocator() );
+
+ node_a = {};
+ node_b = std::move(node_a); // !empty = empty
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+}
+
+void
+test_alloc_lifetime()
+{
+ Alloc<int> a(1);
+ test_type s({1,2,3}, a);
+ VERIFY( a.id.use_count() == 2 ); // a and the copy in s
+
+ s.insert(s.extract(1));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(s.begin(), s.extract(2));
+ VERIFY( a.id.use_count() == 2 );
+
+ auto node = s.extract(1);
+ VERIFY( a.id.use_count() == 3 );
+ node = s.extract(0);
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(std::move(node));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type(s));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type({4,5,6}, a));
+ VERIFY( a.id.use_count() == 2 );
+}
+
+int main()
+{
+ test_node_ops();
+ test_alloc_lifetime();
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/unordered_multiset/modifiers/114401.cc
b/libstdc++-v3/testsuite/23_containers/unordered_multiset/modifiers/114401.cc
new file mode 100644
index 000000000000..0a6ea77bf317
--- /dev/null
+++
b/libstdc++-v3/testsuite/23_containers/unordered_multiset/modifiers/114401.cc
@@ -0,0 +1,126 @@
+// { dg-do run { target c++17 } }
+
+// PR libstdc++/114401 allocator destructor omitted when reinserting
node_handle
+
+#include <unordered_set>
+#include <memory>
+#include <testsuite_hooks.h>
+
+template<typename T>
+struct Alloc
+{
+ using value_type = T;
+ using propagate_on_container_copy_assignment = std::true_type;
+ using propagate_on_container_move_assignment = std::true_type;
+ using propagate_on_container_swap = std::true_type;
+
+ Alloc(int identity) : id(std::make_shared<int>(identity)) { }
+
+ template<typename U>
+ Alloc(const Alloc<U> a) : id(a.id) { }
+
+ T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
+ void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n);
}
+
+ template<typename U>
+ friend bool
+ operator==(const Alloc& a, const Alloc<U>& a2)
+ { return a.id == a2.id; }
+
+ template<typename U>
+ friend bool
+ operator!=(const Alloc& a, const Alloc<U>& a2)
+ { return !(a == a2); }
+
+ std::shared_ptr<int> id;
+};
+
+using test_type
+ = std::unordered_multiset<int, std::hash<int>, std::equal_to<int>,
Alloc<int>>;
+
+void
+test_node_ops()
+{
+ test_type s1({1,3,5}, 3, Alloc<int>(1));
+ test_type s2({2,4,6,8}, 4, Alloc<int>(2));
+ VERIFY( s1.get_allocator() != s2.get_allocator() );
+
+ auto node_a = s1.extract(1);
+ VERIFY( ! node_a.empty() );
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+
+ node_a = std::move(node_a); // self-move
+ VERIFY( node_a.empty() );
+
+ swap(node_a, node_a); // self-swap
+ VERIFY( node_a.empty() );
+
+ auto node_b = s2.extract(2);
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ node_a = std::move(node_b); // empty = !empty
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(!empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ node_a = s1.extract(3); // !empty = !empty
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+ node_b = s2.extract(0); // empty = empty
+ VERIFY( node_b.empty() );
+ node_b = s2.extract(6); // empty = !empty
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(!empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.get_allocator() == s1.get_allocator() );
+
+ node_a = {};
+ node_b = std::move(node_a); // !empty = empty
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+}
+
+void
+test_alloc_lifetime()
+{
+ Alloc<int> a(1);
+ test_type s({1,2,3}, 3, a);
+ VERIFY( a.id.use_count() == 2 ); // a and the copy in s
+
+ s.insert(s.extract(1));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(s.begin(), s.extract(2));
+ VERIFY( a.id.use_count() == 2 );
+
+ auto node = s.extract(1);
+ VERIFY( a.id.use_count() == 3 );
+ node = s.extract(0);
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(std::move(node));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type(s));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type({4,5,6}, 3, a));
+ VERIFY( a.id.use_count() == 2 );
+}
+
+int main()
+{
+ test_node_ops();
+ test_alloc_lifetime();
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/114401.cc
b/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/114401.cc
new file mode 100644
index 000000000000..3ae2f2d5b5c3
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/114401.cc
@@ -0,0 +1,126 @@
+// { dg-do run { target c++17 } }
+
+// PR libstdc++/114401 allocator destructor omitted when reinserting
node_handle
+
+#include <unordered_set>
+#include <memory>
+#include <testsuite_hooks.h>
+
+template<typename T>
+struct Alloc
+{
+ using value_type = T;
+ using propagate_on_container_copy_assignment = std::true_type;
+ using propagate_on_container_move_assignment = std::true_type;
+ using propagate_on_container_swap = std::true_type;
+
+ Alloc(int identity) : id(std::make_shared<int>(identity)) { }
+
+ template<typename U>
+ Alloc(const Alloc<U> a) : id(a.id) { }
+
+ T* allocate(std::size_t n) { return std::allocator<T>().allocate(n); }
+ void deallocate(T* p, std::size_t n) { std::allocator<T>().deallocate(p, n);
}
+
+ template<typename U>
+ friend bool
+ operator==(const Alloc& a, const Alloc<U>& a2)
+ { return a.id == a2.id; }
+
+ template<typename U>
+ friend bool
+ operator!=(const Alloc& a, const Alloc<U>& a2)
+ { return !(a == a2); }
+
+ std::shared_ptr<int> id;
+};
+
+using test_type
+ = std::unordered_set<int, std::hash<int>, std::equal_to<int>, Alloc<int>>;
+
+void
+test_node_ops()
+{
+ test_type s1({1,3,5}, 3, Alloc<int>(1));
+ test_type s2({2,4,6,8}, 4, Alloc<int>(2));
+ VERIFY( s1.get_allocator() != s2.get_allocator() );
+
+ auto node_a = s1.extract(1);
+ VERIFY( ! node_a.empty() );
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+
+ node_a = std::move(node_a); // self-move
+ VERIFY( node_a.empty() );
+
+ swap(node_a, node_a); // self-swap
+ VERIFY( node_a.empty() );
+
+ auto node_b = s2.extract(2);
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ node_a = std::move(node_b); // empty = !empty
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(!empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.empty() );
+
+ node_a = s1.extract(3); // !empty = !empty
+ VERIFY( node_a.get_allocator() == s1.get_allocator() );
+ node_b = s2.extract(0); // empty = empty
+ VERIFY( node_b.empty() );
+ node_b = s2.extract(6); // empty = !empty
+ VERIFY( node_b.get_allocator() == s2.get_allocator() );
+
+ swap(node_a, node_b); // swap(!empty, !empty)
+ VERIFY( node_a.get_allocator() == s2.get_allocator() );
+ VERIFY( node_b.get_allocator() == s1.get_allocator() );
+
+ node_a = {};
+ node_b = std::move(node_a); // !empty = empty
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+
+ swap(node_a, node_b); // swap(empty, empty)
+ VERIFY( node_a.empty() );
+ VERIFY( node_b.empty() );
+}
+
+void
+test_alloc_lifetime()
+{
+ Alloc<int> a(1);
+ test_type s({1,2,3}, 3, a);
+ VERIFY( a.id.use_count() == 2 ); // a and the copy in s
+
+ s.insert(s.extract(1));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(s.begin(), s.extract(2));
+ VERIFY( a.id.use_count() == 2 );
+
+ auto node = s.extract(1);
+ VERIFY( a.id.use_count() == 3 );
+ node = s.extract(0);
+ VERIFY( a.id.use_count() == 2 );
+
+ s.insert(std::move(node));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type(s));
+ VERIFY( a.id.use_count() == 2 );
+
+ s.merge(test_type({4,5,6}, 3, a));
+ VERIFY( a.id.use_count() == 2 );
+}
+
+int main()
+{
+ test_node_ops();
+ test_alloc_lifetime();
+}
