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

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Ion Gaztañaga
2019-04-30 18:05:50 +02:00
parent 909ccf6057
commit 5f0ce60b39
7 changed files with 151 additions and 146 deletions
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include/boost/container/string.hpp
+22 -22
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@@ -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::
@@ -896,27 +896,27 @@ 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.
BOOST_ASSERT(this != &x);
allocator_type &this_alloc = this->alloc();
allocator_type &x_alloc = x.alloc();
const bool propagate_alloc = allocator_traits_type::
propagate_on_container_move_assignment::value;
dtl::bool_<propagate_alloc> flag;
const bool allocators_equal = this_alloc == x_alloc; (void)allocators_equal;
//Resources can be transferred if both allocators are
//going to be equal after this function (either propagated or already equal)
if(propagate_alloc || allocators_equal){
//Destroy objects but retain memory in case x reuses it in the future
this->clear();
//Move allocator if needed
dtl::move_alloc(this_alloc, x_alloc, flag);
//Nothrow swap
this->swap_data(x);
}
//Else do a one by one move
else{
this->assign( x.begin(), x.end());
if (BOOST_LIKELY(this != &x)) {
allocator_type &this_alloc = this->alloc();
allocator_type &x_alloc = x.alloc();
const bool propagate_alloc = allocator_traits_type::
propagate_on_container_move_assignment::value;
dtl::bool_<propagate_alloc> flag;
const bool allocators_equal = this_alloc == x_alloc; (void)allocators_equal;
//Resources can be transferred if both allocators are
//going to be equal after this function (either propagated or already equal)
if(propagate_alloc || allocators_equal){
//Destroy objects but retain memory in case x reuses it in the future
this->clear();
//Move allocator if needed
dtl::move_alloc(this_alloc, x_alloc, flag);
//Nothrow swap
this->swap_data(x);
}
//Else do a one by one move
else{
this->assign( x.begin(), x.end());
}
}
return *this;
}