[v3] C++11 allocator reqs for vector in debug & profile mode

Jonathan Wakely jwakely.gcc@gmail.com
Mon Nov 14 21:15:00 GMT 2011


On 14 November 2011 20:15, François Dumont wrote:
>    I wonder if playing with allocator propagation in such a context is
> right. The Standard define shrink_to_fit as a member method and not as a
> global function. People implementing an allocator might not expect
> allocators to be copy or anything else when calling vector::shrink_to_fit
> which can normally be implemented without it.

I don't see what being a member function or global function has to do
with anything.

Allocators must be copyable, containers take a copy of an allocator,
if copying them misbehaves then you're in big trouble, long before
calling shrink_to_fit.

Could you explain why you think the current code is a problem?

My change ensures that the new storage is created with the same
allocator, so whether propagate_on_container_swap is true or not, the
container ends up with the same allocator it had originally (or a copy
of it) and storage that can be freed by that allocator.



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