Sent from my HTC ----- Reply message ----- From: "Jonathan Wakely" To: "boost@lists.boost.org" Subject: [boost] ASIO into the standard (was: Re: C++ committee meeting report) Date: Fri, Jul 4, 2014 15:45 On 4 July 2014 12:44, Niall Douglas wrote:

There are lots of things going on here. STL allocators were always half baked because they were never finished - John Lakos is but one of many who took them to all sorts of interesting new places, indeed Stepanov's original design had enormous potential. Unfortunately, we've ended up stuck with these half finished things, and now they are creating slow path performance with std::vector because STL containers can't have a noexcept move constructor due to allocators!

That's not txrue, the move constructor always propagates the allocator so doesn't need to re-allocate. The reason for it not being noexcept is not because of allocators, and at the last meeting we agreed that vector and string should have noexcept move constructors, always. Move assignment might need to reallocate for non-equal allocators, so that can't always be noexcept (but the implementation can add a conditional noexcept using the propagate_on_container_move_assignment trait, if your vendor doesn't do that complain to them :-) _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost