http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55043
--- Comment #19 from Paolo Carlini <paolo.carlini at oracle dot com> 2012-10-24 18:51:24 UTC --- Essentially memory allocation is needed because that is the "simplest" state for such containers, what the default constructor also does in other terms. Given that the moved from container must remain in a sane state and all the normal operations must still be well defined, I don't think we can have something "simpler", thus not allocating memory, than the default constructed state. We can of course in principle redesign the affected containers to have a different, simpler, default (it's already the case for containers like vector or list, of course) but that isn't that easy to do, AFAICS. That said, I'm not convinced this is the *real* issue, because: 1- I think a move-constructor not noexcept is still conforming; 2- As we often say when teaching these things, the std:: containers are just *examples* from the generic programming point of view, and we should anyway be ready for user code with throwing move constructors...
