PR libstdc++/82522 overload map insert functions for rvalues (LWG 2354)

	PR libstdc++/82522
	* doc/xml/manual/intro.xml: Document LWG 2354 changes.
	* include/bits/stl_map.h (map::insert(value_type&&))
	(map::insert(const_iterator, value_type&&)): Add overload for rvalues.
	* include/bits/stl_multimap.h (multimap::insert(value_type&&))
	(multimap::insert(const_iterator, value_type&&)): Likewise.
	* include/bits/unordered_map.h (unordered_map::insert(value_type&&))
	(unordered_map::insert(const_iterator, value_type&&))
	(unordered_multimap::insert(value_type&&))
	(unordered_multimap::insert(const_iterator, value_type&&)): Likewise.
	* testsuite/23_containers/map/modifiers/insert/dr2354.cc: New test.
	* testsuite/23_containers/multimap/modifiers/insert/dr2354.cc: New
	test.
	* testsuite/23_containers/unordered_map/insert/dr2354.cc: New test.
	* testsuite/23_containers/unordered_multimap/insert/dr2354.cc: New
	test.

From-SVN: r253725

3 files changed, 54 insertions, 1 deletions

diff --git a/libstdc++-v3/include/bits/stl_map.h b/libstdc++-v3/include/bits/stl_map.h
index 0e8a98a..bad6020 100644
--- a/libstdc++-v3/include/bits/stl_map.h
+++ b/libstdc++-v3/include/bits/stl_map.h
@@ -778,7 +778,6 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 
       /**
        *  @brief Attempts to insert a std::pair into the %map.
-
        *  @param __x Pair to be inserted (see std::make_pair for easy
        *	     creation of pairs).
        *
@@ -791,12 +790,19 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  first element (the key) is not already present in the %map.
        *
        *  Insertion requires logarithmic time.
+       *  @{
        */
       std::pair<iterator, bool>
       insert(const value_type& __x)
       { return _M_t._M_insert_unique(__x); }
 
 #if __cplusplus >= 201103L
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      std::pair<iterator, bool>
+      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>
@@ -804,6 +810,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	insert(_Pair&& __x)
 	{ return _M_t._M_insert_unique(std::forward<_Pair>(__x)); }
 #endif
+      // @}
 
 #if __cplusplus >= 201103L
       /**
@@ -840,6 +847,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  for more on @a hinting.
        *
        *  Insertion requires logarithmic time (if the hint is not taken).
+       *  @{
        */
       iterator
 #if __cplusplus >= 201103L
@@ -850,6 +858,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       { return _M_t._M_insert_unique_(__position, __x); }
 
 #if __cplusplus >= 201103L
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      iterator
+      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>
@@ -858,6 +872,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	{ return _M_t._M_insert_unique_(__position,
 					std::forward<_Pair>(__x)); }
 #endif
+      // @}
 
       /**
        *  @brief Template function that attempts to insert a range of elements.
diff --git a/libstdc++-v3/include/bits/stl_multimap.h b/libstdc++-v3/include/bits/stl_multimap.h
index 7e3cea4..6f5cb7a 100644
--- a/libstdc++-v3/include/bits/stl_multimap.h
+++ b/libstdc++-v3/include/bits/stl_multimap.h
@@ -526,12 +526,19 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  thus multiple pairs with the same key can be inserted.
        *
        *  Insertion requires logarithmic time.
+       *  @{
        */
       iterator
       insert(const value_type& __x)
       { return _M_t._M_insert_equal(__x); }
 
 #if __cplusplus >= 201103L
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      iterator
+      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>
@@ -539,6 +546,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	insert(_Pair&& __x)
 	{ return _M_t._M_insert_equal(std::forward<_Pair>(__x)); }
 #endif
+      // @}
 
       /**
        *  @brief Inserts a std::pair into the %multimap.
@@ -559,6 +567,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
        *
        *  Insertion requires logarithmic time (if the hint is not taken).
+       * @{
        */
       iterator
 #if __cplusplus >= 201103L
@@ -569,6 +578,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       { return _M_t._M_insert_equal_(__position, __x); }
 
 #if __cplusplus >= 201103L
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      iterator
+      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>
@@ -577,6 +592,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	{ return _M_t._M_insert_equal_(__position,
 				       std::forward<_Pair>(__x)); }
 #endif
+      // @}
 
       /**
        *  @brief A template function that attempts to insert a range
diff --git a/libstdc++-v3/include/bits/unordered_map.h b/libstdc++-v3/include/bits/unordered_map.h
index df1302c..2fd4cd5 100644
--- a/libstdc++-v3/include/bits/unordered_map.h
+++ b/libstdc++-v3/include/bits/unordered_map.h
@@ -579,6 +579,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       insert(const value_type& __x)
       { return _M_h.insert(__x); }
 
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      std::pair<iterator, bool>
+      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>
@@ -613,6 +619,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       insert(const_iterator __hint, const value_type& __x)
       { return _M_h.insert(__hint, __x); }
 
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      iterator
+      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>
@@ -1468,6 +1480,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       insert(const value_type& __x)
       { return _M_h.insert(__x); }
 
+      iterator
+      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>
@@ -1500,6 +1516,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       insert(const_iterator __hint, const value_type& __x)
       { return _M_h.insert(__hint, __x); }
 
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // 2354. Unnecessary copying when inserting into maps with braced-init
+      iterator
+      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>