[PATCH] Optimize inserting value_type into std::vector

[Jonathan Wakely]

On 18/06/16 10:41 +0800, Yubin Ruan wrote:
>my question is in regard to the two lines below
>
>>   *end() = std::move(*it);
>>   ++this->_M_impl._M_finish;
>
>Isn't it illegal to dereference `end()` ?

It was just pseudocode really (the code I gave doesn't work with
allocators that use non-builtin pointers).  The first line above
should be:

  allocator_traits<allocator_type>::construct(get_allocator(),
                                              data()+size(),
                                              std::move(*it));

>what does `++this->_M_impl._M_finish` do here ?

It updates the size of the vector, to include the new element
constructed at the end.

>Any libstdc++ specified stuff here ?

Obviously _M_impl._M_finish is specific to our implementation, but
others will have something similar with different names.