id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
9644,Containers and move-only elements w/Move Emulation,John M. Długosz <mpbecey7gu@…>,Ion Gaztañaga,"The definition of boost::container::vector includes: BOOST_COPYABLE_AND_MOVABLE
rather than BOOST_MOVABLE_BUT_NOT_COPYABLE if the element type cannot be copied.

If I have:

{{{
    typedef boost::container::vector<MyType> VecType;

    VecType foo()
        {
        ⋮
        return boost::move(some_other_vec);
        }

    VecType x= foo();
}}}


On a configuration with BOOST_NO_RVALUE_REFERENCES defined, this gives an error within VecType's copy constructor, since MyType cannot be copied.

If I write

{{{
    VecType x= boost::move(foo());
}}}

then I get an error that no matching move is viable, as the move(T&) wants an lvalue as the argument.

I can't write the return type of foo to be rv<VecType> because that can't be copied (fake move-out like auto_pointer) either; the members are declared private and never defined.

This is a bug on Boost.Container, as it defines the copy constructor and the move emulation is not good enough to avoid the defined copy constructor.

(The project I found this on was using Boost 1.49.  It is unchanged in the current version, but I've not tested it on that.)",Bugs,closed,To Be Determined,container,Boost 1.49.0,Problem,wontfix,,igaztanaga@…