From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id 5E809385841A; Fri, 22 Mar 2024 22:51:19 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5E809385841A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1711147879; bh=gsz+PNMVwTOtyFHt0xUmPw7XbwnVKH+bINVIMDmFKW0=; h=From:To:Subject:Date:From; b=HqyL7LP9nZ+u8Rp7Awx4NFWdIw8CIIe4uX3jby+ShL/JSnQS0QehVae3A7mLnby9J PHdYxpxZBfVUCiVZkL0pfni0lOUMNaXnf30AUekK7tQ5/8kgSIguwaw07iwQSz35Zj +CxksRZBlrrfdubRNs6nRvN2mBA5M3KBcjanPqu8= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r14-9636] libstdc++: Destroy allocators in re-inserted container nodes [PR114401] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/master X-Git-Oldrev: 142cc4c223d695e515ed2504501b91d8a7ac6eb8 X-Git-Newrev: c2e28df90a1640cebadef6c6c8ab5ea964071bb1 Message-Id: <20240322225119.5E809385841A@sourceware.org> Date: Fri, 22 Mar 2024 22:51:19 +0000 (GMT) List-Id: https://gcc.gnu.org/g:c2e28df90a1640cebadef6c6c8ab5ea964071bb1 commit r14-9636-gc2e28df90a1640cebadef6c6c8ab5ea964071bb1 Author: Jonathan Wakely 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 nothign 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. (_Hashtable::_M_merge_multi): 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. Diff: --- libstdc++-v3/include/bits/hashtable.h | 12 +- libstdc++-v3/include/bits/node_handle.h | 19 +++- libstdc++-v3/include/bits/stl_tree.h | 12 +- .../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, 530 insertions(+), 15 deletions(-) diff --git a/libstdc++-v3/include/bits/hashtable.h b/libstdc++-v3/include/bits/hashtable.h index c3ef7a0a3d5..cd3e1ac297c 100644 --- a/libstdc++-v3/include/bits/hashtable.h +++ b/libstdc++-v3/include/bits/hashtable.h @@ -1036,7 +1036,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // DR 1189. // reserve, if present, comes from _Rehash_base. -#if __cplusplus > 201402L +#if __glibcxx_node_extract // >= C++17 /// Re-insert an extracted node into a container with unique keys. insert_return_type _M_reinsert_node(node_type&& __nh) @@ -1078,7 +1078,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { __ret.position = _M_insert_unique_node(__bkt, __code, __nh._M_ptr); - __nh._M_ptr = nullptr; + __nh.release(); __ret.inserted = true; } } @@ -1098,7 +1098,7 @@ _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; } @@ -1200,7 +1200,7 @@ _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) @@ -1227,10 +1227,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION = _M_src_hash_code(__src.hash_function(), __k, *__pos._M_cur); auto __nh = __src.extract(__pos); __hint = _M_insert_multi_node(__hint, __code, __nh._M_ptr)._M_cur; - __nh._M_ptr = nullptr; + __nh.release(); } } -#endif // C++17 +#endif // C++17 __glibcxx_node_extract private: // Helper rehash method used when keys are unique. diff --git a/libstdc++-v3/include/bits/node_handle.h b/libstdc++-v3/include/bits/node_handle.h index bd9b1afc8d7..2d8e47c5062 100644 --- a/libstdc++-v3/include/bits/node_handle.h +++ b/libstdc++-v3/include/bits/node_handle.h @@ -169,6 +169,16 @@ _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; @@ -220,9 +230,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION return __tmp; } - struct _Empty { }; - - [[__no_unique_address__]] _Empty _M_empty; [[__no_unique_address__]] _NodeAlloc _M_alloc; }; @@ -232,6 +239,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION typename _Compare, typename _ValueAlloc> friend class _Rb_tree; + template + friend class _Hashtable; + /// @endcond }; diff --git a/libstdc++-v3/include/bits/stl_tree.h b/libstdc++-v3/include/bits/stl_tree.h index 6f470f04f6a..978093fc587 100644 --- a/libstdc++-v3/include/bits/stl_tree.h +++ b/libstdc++-v3/include/bits/stl_tree.h @@ -1431,7 +1431,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _M_move_assign(_Rb_tree&, false_type); #endif -#if __cplusplus > 201402L +#if __glibcxx_node_extract // >= C++17 public: /// Re-insert an extracted node. insert_return_type @@ -1449,7 +1449,7 @@ _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 @@ -1477,7 +1477,7 @@ _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; } @@ -1496,7 +1496,7 @@ _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); @@ -1519,7 +1519,7 @@ _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; } @@ -1595,7 +1595,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION } } } -#endif // C++17 +#endif // C++17 node_extract friend bool operator==(const _Rb_tree& __x, const _Rb_tree& __y) 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 00000000000..630e18e287c --- /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 +#include +#include + +template +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(identity)) { } + + template + Alloc(const Alloc a) : id(a.id) { } + + T* allocate(std::size_t n) { return std::allocator().allocate(n); } + void deallocate(T* p, std::size_t n) { std::allocator().deallocate(p, n); } + + template + friend bool + operator==(const Alloc& a, const Alloc& a2) + { return a.id == a2.id; } + + template + friend bool + operator!=(const Alloc& a, const Alloc& a2) + { return !(a == a2); } + + std::shared_ptr id; +}; + +using test_type = std::multiset, Alloc>; + +void +test_node_ops() +{ + test_type s1({1,3,5}, Alloc(1)); + test_type s2({2,4,6,8}, Alloc(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 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 00000000000..f0a06a8c1a2 --- /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 +#include +#include + +template +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(identity)) { } + + template + Alloc(const Alloc a) : id(a.id) { } + + T* allocate(std::size_t n) { return std::allocator().allocate(n); } + void deallocate(T* p, std::size_t n) { std::allocator().deallocate(p, n); } + + template + friend bool + operator==(const Alloc& a, const Alloc& a2) + { return a.id == a2.id; } + + template + friend bool + operator!=(const Alloc& a, const Alloc& a2) + { return !(a == a2); } + + std::shared_ptr id; +}; + +using test_type = std::set, Alloc>; + +void +test_node_ops() +{ + test_type s1({1,3,5}, Alloc(1)); + test_type s2({2,4,6,8}, Alloc(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 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 00000000000..0a6ea77bf31 --- /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 +#include +#include + +template +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(identity)) { } + + template + Alloc(const Alloc a) : id(a.id) { } + + T* allocate(std::size_t n) { return std::allocator().allocate(n); } + void deallocate(T* p, std::size_t n) { std::allocator().deallocate(p, n); } + + template + friend bool + operator==(const Alloc& a, const Alloc& a2) + { return a.id == a2.id; } + + template + friend bool + operator!=(const Alloc& a, const Alloc& a2) + { return !(a == a2); } + + std::shared_ptr id; +}; + +using test_type + = std::unordered_multiset, std::equal_to, Alloc>; + +void +test_node_ops() +{ + test_type s1({1,3,5}, 3, Alloc(1)); + test_type s2({2,4,6,8}, 4, Alloc(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 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 00000000000..3ae2f2d5b5c --- /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 +#include +#include + +template +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(identity)) { } + + template + Alloc(const Alloc a) : id(a.id) { } + + T* allocate(std::size_t n) { return std::allocator().allocate(n); } + void deallocate(T* p, std::size_t n) { std::allocator().deallocate(p, n); } + + template + friend bool + operator==(const Alloc& a, const Alloc& a2) + { return a.id == a2.id; } + + template + friend bool + operator!=(const Alloc& a, const Alloc& a2) + { return !(a == a2); } + + std::shared_ptr id; +}; + +using test_type + = std::unordered_set, std::equal_to, Alloc>; + +void +test_node_ops() +{ + test_type s1({1,3,5}, 3, Alloc(1)); + test_type s2({2,4,6,8}, 4, Alloc(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 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(); +}