Re: [Boost-users] [Boost.Move] Conflict between std::move and boost::move (Boost 1.49.0)

Subject: Re: [Boost-users] [Boost.Move] Conflict between std::move and boost::move (Boost 1.49.0)
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2012-07-10 17:49:05

Le 10/07/12 23:18, Jonathan Jones a écrit :
> Hi folks,
>
> Consider the following code (which distilled from a real world example):
>
>
> #include <boost/move/move.hpp>
> #include <boost/optional/optional.hpp>
> #include <utility>
> #include <vector>
>
> typedef boost::optional<int> data_type;
> typedef std::vector<data_type> vector_type;
>
> vector_type func()
> {
>     vector_type vv;
> return move(vv);
> }
>
>
> If I compile this code using Boost 1.49 on Visual Studio 2010, or on a 
> recent version of g++ (e.g. 4.7.1) which supports some C++11 features, 
> the code fails to compile, complaining about ambiguity between 
> std::move and boost::move.  Strangely, the code compiles fine with 
> Apple Clang version 3.1.
Which compiler has the correct behavior?

> Is there a way to work around the compilation problem which doesn't 
> involve explicitly qualifying the calls to move?  I'd prefer to use 
> argument-dependent-lookup.  Removing the includes of boost/move.hpp is 
> not possible.  In the real world example, that header is included 
> indirectly.
>
> I did notice that if I define the macro 
> BOOST_MOVE_USE_STANDARD_LIBRARY_MOVE, the compilation errors 
> disappear.  Is this the correct approach for compilers which support 
> std::move?  I find it odd that this macro isn't already defined for 
> such compilers.
>
>
It seems you have found the solution. Could you create a ticket so that 
macro is defined when the std library provides std::move? In the 
meantime you could define the macro yourself.

Best,
Vicente