std::vector default default and move constructors

[François Dumont]

On 16/01/2018 01:20, Jonathan Wakely wrote:
> On 15/01/18 22:32 +0100, François Dumont wrote:
>> On 15/01/2018 13:29, Jonathan Wakely wrote:
>>> In fact it introduces a serious regression because of this line:
>>>
>>>> -Â Â Â Â Â  vector(vector&& __x) noexcept
>>>> -Â Â Â Â Â  : _Base(std::move(__x)) { }
>>>> +Â Â Â Â Â  vector(vector&&) = default;
>>>
>>> Consider what happens if we have an allocator that is not
>>> nothrow-move-constructible, which can happen if the allocator has a
>>> noexcept(false) move constructor, or more likely just has no move
>>> constructor but has a noexcept(false) copy constructor:
>>>
> One of the move constructors needs to be defined with a function body,
> not defaulted, so that it can also be declared noexcept

Here is an updated patch with this change. Do you also want an explicit 
noexcept on the vector(vector&&) default declaration ? Ok to commit this 
vector patch ?

I was going to propose a similar patch for vector<bool> but checking 
Standard there is not this noexcept qualification on the move constructor.

François

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