Re: [Boost-users] [boost::variant] problem with swap

Subject: Re: [Boost-users] [boost::variant] problem with swap
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2009-12-20 10:53:08

AMDG

Ondrej Kuncar wrote:
> I have problems to compile this code with Visual Studio 9.0 SP1 and
> Boost 1.41:
>
> -------------------------------------------------------------------
>
> #include <boost/variant.hpp>
> #include <deque>
>
> typedef boost::variant<std::deque<int>::iterator> SemanticValue;
>
> int main() {
> 	SemanticValue v1;
> 	SemanticValue v2;
> 	v1.swap(v2);
> }
>
> -------------------------------------------------------------------
>
> I got this error:
>
> c:\program files\boost\boost_1_41_0\boost\variant\detail\move.hpp(155) :
> error C2668: 'std::swap' : ambiguous call to overloaded function
>         c:\program
> files\boost\boost_1_41_0\boost\variant\detail\move.hpp(141): could be
> 'void boost::detail::variant::detail::move_swap::swap<T>(T &,T &)'
>         with
>         [
>             T=T0
>         ]
>         c:\program files\microsoft visual studio
> 9.0\vc\include\utility(16): or       'void std::swap<T>(_Ty &,_Ty &)'
> [found using argument-dependent lookup]
>         with
>         [
>             T=T0,
>             _Ty=T0
>         ]
>         while trying to match the argument list '(T0, T0)'
> <snip>
>
>
> Do you have any ideas?
>   

This is a known bug.  I believe that there's an open trac ticket
for it.  I don't think anyone has found a good solution yet.

In Christ,
Steven Watanabe