https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86127
--- Comment #7 from Scott Constable <fidget324 at gmail dot com> --- (In reply to Jonathan Wakely from comment #1) > The allocator requirements say that move construction must be equivalent to > copy construction, and allocators should be cheap to copy anyway. I don't > consider this a bug. To be nitpicky, it looks like this equivalence requirement was introduced recently in the C++20 draft. I'm compiling using C++14. I agree that allocators should be cheap to copy, but as a general principle I think that all objects should be copied only when necessary. This is the behavior I have observed in STL containers in libc++, as shown in my example above. It just makes sense to me that when an STL container is moved, its allocator should be moved, and no copying should be performed.
