Fixes #88 ("Implement C++17 MoveAssignable requirements for self-move assignments")

doc/container.qbk

@@ -1267,7 +1267,7 @@ use [*Boost.Container]? There are several reasons for that:
 [section:release_notes Release Notes]
 
 [section:release_notes_boost_1_71_00 Boost 1.71 Release]
-
+   * [@https://github.com/boostorg/container/issues/88 GitHub #88: ['"Implement C++17 MoveAssignable requirements for self-move assignments"]].
    * [@https://github.com/boostorg/container/pull/109  GitHub #109: ['"Get rid of integer overflow in copy_move_algo.hpp (-fsanitize=integer)"]].
    * [@https://github.com/boostorg/container/pull/110  GitHub #110: ['"Avoid gcc 9 deprecated copy warnings in new_allocator.hpp"]].
    * [@https://github.com/boostorg/container/issues/112 GitHub #112: ['"vector::resize() compilation error with msvc-10..12: data is not a member of boost::detail::aligned_storage"]].

include/boost/container/deque.hpp

@@ -811,7 +811,7 @@ class deque : protected deque_base<typename real_allocator<T, Allocator>::type,
    //! <b>Complexity</b>: Linear to the number of elements in x.
    deque& operator= (BOOST_COPY_ASSIGN_REF(deque) x)
    {
-      if (&x != this){
+      if (BOOST_LIKELY(&x != this)){
          allocator_type &this_alloc     = this->alloc();
          const allocator_type &x_alloc  = x.alloc();
          dtl::bool_<allocator_traits_type::
@@ -839,7 +839,7 @@ class deque : protected deque_base<typename real_allocator<T, Allocator>::type,
       BOOST_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value
                                   || allocator_traits_type::is_always_equal::value)
    {
-      BOOST_ASSERT(this != &x);
+      if (BOOST_LIKELY(this != &x)) {
          allocator_type &this_alloc = this->alloc();
          allocator_type &x_alloc    = x.alloc();
          const bool propagate_alloc = allocator_traits_type::
@@ -862,6 +862,7 @@ class deque : protected deque_base<typename real_allocator<T, Allocator>::type,
             this->assign( boost::make_move_iterator(x.begin())
                         , boost::make_move_iterator(x.end()));
          }
+      }
       return *this;
    }
 

include/boost/container/detail/tree.hpp

@@ -788,7 +788,7 @@ class tree
 
    tree& operator=(BOOST_COPY_ASSIGN_REF(tree) x)
    {
-      if (&x != this){
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc     = this->get_stored_allocator();
          const NodeAlloc &x_alloc  = x.get_stored_allocator();
          dtl::bool_<allocator_traits<NodeAlloc>::
@@ -822,7 +822,7 @@ class tree
                           allocator_traits_type::is_always_equal::value) &&
                            boost::container::dtl::is_nothrow_move_assignable<Compare>::value)
    {
-      BOOST_ASSERT(this != &x);
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc = this->node_alloc();
          NodeAlloc &x_alloc    = x.node_alloc();
          const bool propagate_alloc = allocator_traits<NodeAlloc>::
@@ -857,6 +857,7 @@ class tree
                AllocHolder::destroy_node(p);
             }
          }
+      }
       return *this;
    }
 

include/boost/container/list.hpp

@@ -367,7 +367,7 @@ class list
    //! <b>Complexity</b>: Linear to the number of elements in x.
    list& operator=(BOOST_COPY_ASSIGN_REF(list) x)
    {
-      if (&x != this){
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc     = this->node_alloc();
          const NodeAlloc &x_alloc  = x.node_alloc();
          dtl::bool_<allocator_traits_type::
@@ -396,7 +396,7 @@ class list
       BOOST_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value
                                   || allocator_traits_type::is_always_equal::value)
    {
-      BOOST_ASSERT(this != &x);
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc = this->node_alloc();
          NodeAlloc &x_alloc    = x.node_alloc();
          const bool propagate_alloc = allocator_traits_type::
@@ -417,6 +417,7 @@ class list
             this->assign( boost::make_move_iterator(x.begin())
                         , boost::make_move_iterator(x.end()));
          }
+      }
       return *this;
    }
 

include/boost/container/slist.hpp

@@ -395,7 +395,7 @@ class slist
    //! <b>Complexity</b>: Linear to the number of elements in x.
    slist& operator= (BOOST_COPY_ASSIGN_REF(slist) x)
    {
-      if (&x != this){
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc     = this->node_alloc();
          const NodeAlloc &x_alloc  = x.node_alloc();
          dtl::bool_<allocator_traits_type::
@@ -424,7 +424,7 @@ class slist
       BOOST_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value
                                   || allocator_traits_type::is_always_equal::value)
    {
-      BOOST_ASSERT(this != &x);
+      if (BOOST_LIKELY(this != &x)) {
          NodeAlloc &this_alloc = this->node_alloc();
          NodeAlloc &x_alloc    = x.node_alloc();
          const bool propagate_alloc = allocator_traits_type::
@@ -445,6 +445,7 @@ class slist
             this->assign( boost::make_move_iterator(x.begin())
                         , boost::make_move_iterator(x.end()));
          }
+      }
       return *this;
    }
 

include/boost/container/stable_vector.hpp

@@ -823,7 +823,7 @@ class stable_vector
    stable_vector& operator=(BOOST_COPY_ASSIGN_REF(stable_vector) x)
    {
       STABLE_VECTOR_CHECK_INVARIANT;
-      if (&x != this){
+      if (BOOST_LIKELY(this != &x)) {
          node_allocator_type &this_alloc     = this->priv_node_alloc();
          const node_allocator_type &x_alloc  = x.priv_node_alloc();
          dtl::bool_<allocator_traits_type::
@@ -855,7 +855,7 @@ class stable_vector
                                   || allocator_traits_type::is_always_equal::value)
    {
       //for move constructor, no aliasing (&x != this) is assumed.
-      BOOST_ASSERT(this != &x);
+      if (BOOST_LIKELY(this != &x)) {
          node_allocator_type &this_alloc = this->priv_node_alloc();
          node_allocator_type &x_alloc    = x.priv_node_alloc();
          const bool propagate_alloc = allocator_traits_type::
@@ -879,6 +879,7 @@ class stable_vector
             this->assign( boost::make_move_iterator(x.begin())
                         , boost::make_move_iterator(x.end()));
          }
+      }
       return *this;
    }
 

include/boost/container/string.hpp

@@ -865,7 +865,7 @@ class basic_string
    //! <b>Complexity</b>: Linear to the elements x contains.
    basic_string& operator=(BOOST_COPY_ASSIGN_REF(basic_string) x)
    {
-      if (&x != this){
+      if (BOOST_LIKELY(this != &x)) {
          allocator_type &this_alloc     = this->alloc();
          const allocator_type &x_alloc  = x.alloc();
          dtl::bool_<allocator_traits_type::
@@ -896,8 +896,7 @@ class basic_string
       BOOST_NOEXCEPT_IF(allocator_traits_type::propagate_on_container_move_assignment::value
                                   || allocator_traits_type::is_always_equal::value)
    {
-      //for move constructor, no aliasing (&x != this) is assumed.
+      if (BOOST_LIKELY(this != &x)) {
-      BOOST_ASSERT(this != &x);
          allocator_type &this_alloc = this->alloc();
          allocator_type &x_alloc    = x.alloc();
          const bool propagate_alloc = allocator_traits_type::
@@ -918,6 +917,7 @@ class basic_string
          else{
             this->assign( x.begin(), x.end());
          }
+      }
       return *this;
    }