Re: [boost] [interprocess][move] enum template argument fails to be a valid base class

Subject: Re: [boost] [interprocess][move] enum template argument fails to be a valid base class
From: vicente.botet (vicente.botet_at_[hidden])
Date: 2010-04-21 19:26:35

----- Original Message ----- 
From: "vicente.botet" <vicente.botet_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Thursday, April 22, 2010 12:30 AM
Subject: [boost] [interprocess][move] enum template argument fails to be avalid base class

I have find a possible bug on the move emulation on "
Boost::Container::Vector with Enum Template Argument - Not Legal Base Class" http://stackoverflow.com/questions/2678476/boostcontainervector-with-enum-template-argument-not-legal-base-class

As rv inherits from the movable class

template <class T>
class rv : public T
{
   rv();
   ~rv();
   rv(rv const&);
   void operator=(rv const&);
};

it doesn't works for enum types. With gcc 3.4. I get

../../../boost/interprocess/detail/move.hpp:79: error: base type `Test::Types' fails to be a struct or class type.

I don't know if this is a know issue with the move emulation. 

I have tried to add a specialization for is_movable

namespace boost {
namespace interprocess { // get inside boost
template<>
class is_movable<Test::Types> // add custom specialization of is_movable
   : public mpl::bool_<false>
{};
}}

but this doesn't works neither. I have tried to specialize the rv template with

template <>
class rv<Test::Types> 
{
   Test::Types v;
   rv();
   ~rv();
   rv(rv const&);
   void operator=(rv const&);
   operator Test::Types() const {return v;}
};

and it compiles but the execution fails.

Is there any workaround to this issue or better yet a generic solution?

_______________________________________________

Sorry, the execution doesn't fails with cygwin 3.4 or msvc 9 Express. I'm not sure if the rv specialization works on all the cases. Ion could you comment on this issue?

Best,
_____________________
Vicente Juan Botet Escribá
http://viboes.blogspot.com/