C++14 simplified the specification of the generic insert function
templates to be equivalent to calling emplace (or emplace_hint).
Defining them in terms of emplace takes care of the problems described
in PR 78595, ensuring a single conversion to value_type is done at the
right time.
PR libstdc++/78595
* include/bits/stl_map.h (map::insert(_Pair&&))
(map::insert(const_iterator, _Pair&&)): Do emplace instead of insert.
* include/bits/stl_multimap.h (multimap::insert(_Pair&&))
(multimap::insert(const_iterator, _Pair&&)): Likewise.
* include/bits/unordered_map.h (unordered_map::insert(_Pair&&))
(unordered_map::insert(const_iterator, _Pair&&))
(unordered_multimap::insert(_Pair&&))
(unordered_multimap::insert(const_iterator, _Pair&&)): Likewise.
* testsuite/23_containers/map/modifiers/insert/78595.cc: New test.
* testsuite/23_containers/multimap/modifiers/insert/78595.cc: New test.
* testsuite/23_containers/unordered_map/modifiers/78595.cc: New test.
* testsuite/23_containers/unordered_multimap/modifiers/78595.cc: New
test.
Tested x86_64-linux, committed to trunk.
commit 29118cb0aa7cfee613b2f597421532562fd53318
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Mon Sep 3 13:49:09 2018 +0100
PR libstdc++/78595 implement insertion into maps in terms of emplace
C++14 simplified the specification of the generic insert function
templates to be equivalent to calling emplace (or emplace_hint).
Defining them in terms of emplace takes care of the problems described
in PR 78595, ensuring a single conversion to value_type is done at the
right time.
PR libstdc++/78595
* include/bits/stl_map.h (map::insert(_Pair&&))
(map::insert(const_iterator, _Pair&&)): Do emplace instead of
insert.
* include/bits/stl_multimap.h (multimap::insert(_Pair&&))
(multimap::insert(const_iterator, _Pair&&)): Likewise.
* include/bits/unordered_map.h (unordered_map::insert(_Pair&&))
(unordered_map::insert(const_iterator, _Pair&&))
(unordered_multimap::insert(_Pair&&))
(unordered_multimap::insert(const_iterator, _Pair&&)): Likewise.
* testsuite/23_containers/map/modifiers/insert/78595.cc: New test.
* testsuite/23_containers/multimap/modifiers/insert/78595.cc: New
test.
* testsuite/23_containers/unordered_map/modifiers/78595.cc: New
test.
* testsuite/23_containers/unordered_multimap/modifiers/78595.cc: New
test.
diff --git a/libstdc++-v3/include/bits/stl_map.h
b/libstdc++-v3/include/bits/stl_map.h
index fdd058b060d..6ce9c3e1f60 100644
--- a/libstdc++-v3/include/bits/stl_map.h
+++ b/libstdc++-v3/include/bits/stl_map.h
@@ -808,12 +808,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(value_type&& __x)
{ return _M_t._M_insert_unique(std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- std::pair<iterator, bool>
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair>::value,
+ pair<iterator, bool>>
insert(_Pair&& __x)
- { return _M_t._M_insert_unique(std::forward<_Pair>(__x)); }
+ { return _M_t._M_emplace_unique(std::forward<_Pair>(__x)); }
#endif
// @}
@@ -869,13 +868,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(const_iterator __position, value_type&& __x)
{ return _M_t._M_insert_unique_(__position, std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
insert(const_iterator __position, _Pair&& __x)
- { return _M_t._M_insert_unique_(__position,
- std::forward<_Pair>(__x)); }
+ {
+ return _M_t._M_emplace_hint_unique(__position,
+ std::forward<_Pair>(__x));
+ }
#endif
// @}
diff --git a/libstdc++-v3/include/bits/stl_multimap.h
b/libstdc++-v3/include/bits/stl_multimap.h
index 9357d1db6aa..d4973870763 100644
--- a/libstdc++-v3/include/bits/stl_multimap.h
+++ b/libstdc++-v3/include/bits/stl_multimap.h
@@ -544,12 +544,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(value_type&& __x)
{ return _M_t._M_insert_equal(std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
insert(_Pair&& __x)
- { return _M_t._M_insert_equal(std::forward<_Pair>(__x)); }
+ { return _M_t._M_emplace_equal(std::forward<_Pair>(__x)); }
#endif
// @}
@@ -589,13 +587,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(const_iterator __position, value_type&& __x)
{ return _M_t._M_insert_equal_(__position, std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator>
insert(const_iterator __position, _Pair&& __x)
- { return _M_t._M_insert_equal_(__position,
- std::forward<_Pair>(__x)); }
+ {
+ return _M_t._M_emplace_hint_equal(__position,
+ std::forward<_Pair>(__x));
+ }
#endif
// @}
diff --git a/libstdc++-v3/include/bits/unordered_map.h
b/libstdc++-v3/include/bits/unordered_map.h
index 9a9332f0305..94ce8cdb482 100644
--- a/libstdc++-v3/include/bits/unordered_map.h
+++ b/libstdc++-v3/include/bits/unordered_map.h
@@ -585,12 +585,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(value_type&& __x)
{ return _M_h.insert(std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- std::pair<iterator, bool>
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair&&>::value,
+ pair<iterator, bool>>
insert(_Pair&& __x)
- { return _M_h.insert(std::forward<_Pair>(__x)); }
+ { return _M_h.emplace(std::forward<_Pair>(__x)); }
//@}
//@{
@@ -625,12 +624,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(const_iterator __hint, value_type&& __x)
{ return _M_h.insert(__hint, std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator>
insert(const_iterator __hint, _Pair&& __x)
- { return _M_h.insert(__hint, std::forward<_Pair>(__x)); }
+ { return _M_h.emplace_hint(__hint, std::forward<_Pair>(__x)); }
//@}
/**
@@ -1571,12 +1568,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(value_type&& __x)
{ return _M_h.insert(std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator>
insert(_Pair&& __x)
- { return _M_h.insert(std::forward<_Pair>(__x)); }
+ { return _M_h.emplace(std::forward<_Pair>(__x)); }
//@}
//@{
@@ -1609,12 +1604,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
insert(const_iterator __hint, value_type&& __x)
{ return _M_h.insert(__hint, std::move(__x)); }
- template<typename _Pair, typename = typename
- std::enable_if<std::is_constructible<value_type,
- _Pair&&>::value>::type>
- iterator
+ template<typename _Pair>
+ __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator>
insert(const_iterator __hint, _Pair&& __x)
- { return _M_h.insert(__hint, std::forward<_Pair>(__x)); }
+ { return _M_h.emplace_hint(__hint, std::forward<_Pair>(__x)); }
//@}
/**
diff --git a/libstdc++-v3/testsuite/23_containers/map/modifiers/insert/78595.cc
b/libstdc++-v3/testsuite/23_containers/map/modifiers/insert/78595.cc
new file mode 100644
index 00000000000..187d165b083
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/map/modifiers/insert/78595.cc
@@ -0,0 +1,115 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+
+#include <map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ struct X {
+ mutable int conversions = 0;
+
+ operator std::pair<const int, int>() const {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::map<int, int> m;
+ m.insert(X());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), X());
+ VERIFY( m.size() == 1 );
+
+}
+void
+test02()
+{
+ struct Y {
+ int conversions = 0;
+
+ operator std::pair<const int, int>() && {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::map<int, int> m;
+ m.insert(Y());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), Y());
+ VERIFY( m.size() == 1 );
+}
+
+struct Key {
+ int key;
+ bool operator<(const Key& r) const { return key < r.key; }
+};
+
+struct Z {
+ operator std::pair<const Key, int>() const { return { { z }, 0 }; }
+ int z;
+};
+
+template<typename T>
+struct Alloc
+{
+ Alloc() = default;
+
+ template<typename U>
+ Alloc(const Alloc<U>&) { }
+
+ using value_type = T;
+
+ 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>
+ void construct(U* p, const Z& z) { ::new (p) U{ { z.z+1 }, 0}; }
+
+ template<typename U>
+ bool operator==(const Alloc<U>&) { return true; }
+
+ template<typename U>
+ bool operator!=(const Alloc<U>&) { return false; }
+};
+
+void
+test03()
+{
+ std::map<Key, int, std::less<Key>, Alloc<std::pair<const Key, int>>> m;
+ m.insert(Z{});
+ m.insert(Z{});
+ VERIFY( m.size() == 1 );
+ m.insert(Z{});
+ m.insert(Z{1});
+ VERIFY( m.size() == 2 );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+ test03();
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/multimap/modifiers/insert/78595.cc
b/libstdc++-v3/testsuite/23_containers/multimap/modifiers/insert/78595.cc
new file mode 100644
index 00000000000..2f357fcae95
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/multimap/modifiers/insert/78595.cc
@@ -0,0 +1,115 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+
+#include <map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ struct X {
+ mutable int conversions = 0;
+
+ operator std::pair<const int, int>() const {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::multimap<int, int> m;
+ m.insert(X());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), X());
+ VERIFY( m.size() == 2 );
+
+}
+void
+test02()
+{
+ struct Y {
+ int conversions = 0;
+
+ operator std::pair<const int, int>() && {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::multimap<int, int> m;
+ m.insert(Y());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), Y());
+ VERIFY( m.size() == 2 );
+}
+
+struct Key {
+ int key;
+ bool operator<(const Key& r) const { return key < r.key; }
+};
+
+struct Z {
+ operator std::pair<const Key, int>() const { return { { z }, 0 }; }
+ int z;
+};
+
+template<typename T>
+struct Alloc
+{
+ Alloc() = default;
+
+ template<typename U>
+ Alloc(const Alloc<U>&) { }
+
+ using value_type = T;
+
+ 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>
+ void construct(U* p, const Z& z) { ::new (p) U{ { z.z+1 }, 0}; }
+
+ template<typename U>
+ bool operator==(const Alloc<U>&) { return true; }
+
+ template<typename U>
+ bool operator!=(const Alloc<U>&) { return false; }
+};
+
+void
+test03()
+{
+ std::multimap<Key, int, std::less<Key>, Alloc<std::pair<const Key, int>>> m;
+ m.insert(Z{});
+ m.insert(Z{});
+ VERIFY( m.size() == 2 );
+ m.insert(Z{});
+ m.insert(Z{1});
+ VERIFY( m.size() == 4 );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+ test03();
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/unordered_map/modifiers/78595.cc
b/libstdc++-v3/testsuite/23_containers/unordered_map/modifiers/78595.cc
new file mode 100644
index 00000000000..47cd67b86d8
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_map/modifiers/78595.cc
@@ -0,0 +1,122 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+
+#include <unordered_map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ struct X {
+ mutable int conversions = 0;
+
+ operator std::pair<const int, int>() const {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::unordered_map<int, int> m;
+ m.insert(X());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), X());
+ VERIFY( m.size() == 1 );
+
+}
+void
+test02()
+{
+ struct Y {
+ int conversions = 0;
+
+ operator std::pair<const int, int>() && {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::unordered_map<int, int> m;
+ m.insert(Y());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), Y());
+ VERIFY( m.size() == 1 );
+}
+
+struct Key {
+ int key;
+ bool operator==(const Key& r) const { return key == r.key; }
+};
+
+namespace std {
+ template<> struct hash<Key> {
+ size_t operator()(const Key& k) const { return std::hash<int>()(k.key); }
+ };
+}
+
+struct Z {
+ operator std::pair<const Key, int>() const { return { { z }, 0 }; }
+ int z;
+};
+
+template<typename T>
+struct Alloc
+{
+ Alloc() = default;
+
+ template<typename U>
+ Alloc(const Alloc<U>&) { }
+
+ using value_type = T;
+
+ 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>
+ void construct(U* p, const Z& z) { ::new (p) U{ { z.z+1 }, 0}; }
+
+ template<typename U>
+ bool operator==(const Alloc<U>&) { return true; }
+
+ template<typename U>
+ bool operator!=(const Alloc<U>&) { return false; }
+};
+
+void
+test03()
+{
+ std::unordered_map<Key, int, std::hash<Key>, std::equal_to<Key>,
+ Alloc<std::pair<const Key, int>>> m;
+ m.insert(Z{});
+ m.insert(Z{});
+ VERIFY( m.size() == 1 );
+ m.insert(Z{});
+ m.insert(Z{1});
+ VERIFY( m.size() == 2 );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+ test03();
+}
diff --git
a/libstdc++-v3/testsuite/23_containers/unordered_multimap/modifiers/78595.cc
b/libstdc++-v3/testsuite/23_containers/unordered_multimap/modifiers/78595.cc
new file mode 100644
index 00000000000..e47c20cad81
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_multimap/modifiers/78595.cc
@@ -0,0 +1,122 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+
+#include <unordered_map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ struct X {
+ mutable int conversions = 0;
+
+ operator std::pair<const int, int>() const {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::unordered_multimap<int, int> m;
+ m.insert(X());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), X());
+ VERIFY( m.size() == 2 );
+
+}
+void
+test02()
+{
+ struct Y {
+ int conversions = 0;
+
+ operator std::pair<const int, int>() && {
+ if (++conversions > 1)
+ throw 1;
+ return {};
+ }
+ };
+
+ std::unordered_multimap<int, int> m;
+ m.insert(Y());
+ VERIFY( m.size() == 1 );
+ m.insert(m.begin(), Y());
+ VERIFY( m.size() == 2 );
+}
+
+struct Key {
+ int key;
+ bool operator==(const Key& r) const { return key == r.key; }
+};
+
+namespace std {
+ template<> struct hash<Key> {
+ size_t operator()(const Key& k) const { return std::hash<int>()(k.key); }
+ };
+}
+
+struct Z {
+ operator std::pair<const Key, int>() const { return { { z }, 0 }; }
+ int z;
+};
+
+template<typename T>
+struct Alloc
+{
+ Alloc() = default;
+
+ template<typename U>
+ Alloc(const Alloc<U>&) { }
+
+ using value_type = T;
+
+ 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>
+ void construct(U* p, const Z& z) { ::new (p) U{ { z.z+1 }, 0}; }
+
+ template<typename U>
+ bool operator==(const Alloc<U>&) { return true; }
+
+ template<typename U>
+ bool operator!=(const Alloc<U>&) { return false; }
+};
+
+void
+test03()
+{
+ std::unordered_multimap<Key, int, std::hash<Key>, std::equal_to<Key>,
+ Alloc<std::pair<const Key, int>>> m;
+ m.insert(Z{});
+ m.insert(Z{});
+ VERIFY( m.size() == 2 );
+ m.insert(Z{});
+ m.insert(Z{1});
+ VERIFY( m.size() == 4 );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+ test03();
+}
