Re: [boost] Boost and auto_ptr (was Boost 1.60.0 beta 1...)

Subject: Re: [boost] Boost and auto_ptr (was Boost 1.60.0 beta 1...)
From: Mateusz Loskot (mateusz_at_[hidden])
Date: 2015-11-10 08:54:53

On 10 November 2015 at 14:31, Vladimir Prus <vladimir.prus_at_[hidden]> wrote:
> On 10-Nov-15 4:08 PM, Andrey Semashev wrote:
>>
>> On 2015-11-10 15:51, Artyom Beilis wrote:
>>>
>>>
>>>> On 2015-11-09 18:52, Marshall Clow wrote:
>>>>
>>>
>>>> [snip]
>>>> I'm seeing lots of warnings about use of deprecated std::auto_ptr in
>>>> >different libraries: Boost.DateTime,
>>>> Boost.Locale, Boost.Signals. I've
>>>> attached the list of places where these warnings occur.
>>>> [snip]
>>>>
>>>
>>>
>>> See... unlike Boost, most of the ordinary world still uses C++2003 and
>>> will use
>>> it for a long time especially for existing projects.
>>>
>>> Existing libraries like Boost.Locale support C++2003.
>>>
>>> std::auto_ptr is perfect way to provide ownership move semantics
>>> without rvalue reference despite the fact some may abuse it.
>>
>>
>> I wouldn't call it perfect. In the lack of rvalue references I would have
>> preferred an explicit method to return a proxy
>> that acts like rvalue reference. But that's offtopic.
>>
>> Would you consider porting Boost.Locale to boost::movelib::unique_ptr from
>> Boost.Move?
>>
>> Note that you will have to switch at some point as MSVC developers are
>> planning to remove auto_ptr from the standard
>> library at some point.
>
>
> Do you have a link saying so? That's quite unfortunate stance, indeed.

I think, this is the relevant announcement:

http://blogs.msdn.com/b/vcblog/archive/2015/04/29/c-11-14-17-features-in-vs-2015-rc.aspx

"""
[2015 opt-in] Available in VS 2015 RC, but guarded by a macro.  By
default, we provide auto_ptr/etc.
If you define _HAS_AUTO_PTR_ETC to 0 project-wide (which you should do
via the command line
or project file, not via #define), then we won't provide auto_ptr/etc.

This opt-in behavior will remain unchanged in 2015 RTM.  In the next
major version,
I'm planning to make this opt-out, and in the major version after
that, I'm planning to eliminate auto_ptr/etc. entirely.
Now would be a good time to start migrating your code.  (I've already
informed Boost's maintainers.)
"""

BTW, I have been asking about _HAS_AUTO_PTR_ETC support too
http://lists.boost.org/boost-users/2015/09/84965.php

Best regards,
-- 
Mateusz  Loskot, http://mateusz.loskot.net