On Mon, Apr 29, 2019 at 12:09 PM Antony Polukhin via Boost < boost@lists.boost.org> wrote:
пн, 29 апр. 2019 г. в 21:52, Steven Watanabe via Boost <
boost@lists.boost.org>:
AMDG
On 4/29/19 11:30 AM, Antony Polukhin via Boost wrote:
I've merged a very cool optimization by Nikita Kniazev into the master branch. From now on boost::variant does pointer stealing for recursive variants.
This significantly improves the performance of the variants move
constructors.
However if you use a variant variable after the std::move for anything except destruction and assignment then you're getting an UB. Beware!
We've had this discussion before: https://lists.boost.org/Archives/boost/2013/02/200744.php
This discussion was considered. Please see the two comments from Nikita Kniazev https://github.com/boostorg/variant/pull/59#issuecomment-459573177
Do I understand correctly that variant no longer provides the basic guarantee, and that's considered an improvement?