[Boost-bugs] [Boost C++ Libraries] #4530: errors with is_convertible on msvc10

Subject: [Boost-bugs] [Boost C++ Libraries] #4530: errors with is_convertible on msvc10
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-08-11 21:58:25

#4530: errors with is_convertible on msvc10
-------------------------------------+--------------------------------------
 Reporter:  cschmidt                 |       Owner:  johnmaddock
     Type:  Bugs                     |      Status:  new        
Milestone:  Boost 1.44.0             |   Component:  type_traits
  Version:  Boost Development Trunk  |    Severity:  Problem    
 Keywords:                           |  
-------------------------------------+--------------------------------------
 {{{
 #include <boost/spirit/include/qi.hpp>
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_convertible.hpp>
 #include <type_traits>

 template<typename T>
 struct test
 {
         template<typename A>
         test(A&&, typename boost::enable_if<boost::is_convertible<A&&, T>
 >::type* =0);
 };

 int main()
 {
         typedef
 boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard,true,false>
 A;

         boost::is_convertible<test<A>, A>::value;
         //std::tr1::is_convertible<test<A>, A>::value;
 }
 }}}

 This snippet fails on msvc10 with the following errors:

 {{{
 1>z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(295): error C2039: 'value'
 : is not a member of 'boost::detail::is_convertible_basic_impl<From,To>'
 1>          with
 1>          [
 1>              From=test<A> ,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(372) : see reference to
 class template instantiation 'boost::detail::is_convertible_impl<From,To>'
 being compiled
 1>          with
 1>          [
 1>              From=test<A> ,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(418) : see reference to
 class template instantiation
 'boost::detail::is_convertible_impl_dispatch<From,To>' being compiled
 1>          with
 1>          [
 1>              From=test<A> ,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\utility\enable_if.hpp(36) : see reference to class
 template instantiation 'boost::is_convertible<From,To>' being compiled
 1>          with
 1>          [
 1>              From=test<A> &,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(263) : see reference to
 class template instantiation 'boost::enable_if<Cond,T>' being compiled
 1>          with
 1>          [
 1>              Cond=boost::is_convertible<test<A> &,A>,
 1>              T=void
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(295) : see reference to
 class template instantiation
 'boost::detail::is_convertible_basic_impl<From,To>' being compiled
 1>          with
 1>          [
 1>              From=test<A> ,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(372) : see reference to
 class template instantiation 'boost::detail::is_convertible_impl<From,To>'
 being compiled
 1>          with
 1>          [
 1>              From=test<A>,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(418) : see reference to
 class template instantiation
 'boost::detail::is_convertible_impl_dispatch<From,To>' being compiled
 1>          with
 1>          [
 1>              From=test<A>,
 1>              To=A
 1>          ]
 1>          z:\dev\projekte\_test\main.cpp(17) : see reference to class
 template instantiation 'boost::is_convertible<From,To>' being compiled
 1>          with
 1>          [
 1>              From=test<A>,
 1>              To=A
 1>          ]
 1>z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(295): error C2065: 'value'
 : undeclared identifier
 1>z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(295): error C2955:
 'boost::type_traits::ice_or' : use of class template requires template
 argument list
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\detail\ice_or.hpp(21) : see declaration of
 'boost::type_traits::ice_or'
 1>z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(295): error C2057: expected
 constant expression
 1>z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\is_convertible.hpp(418): error C2975: 'val' :
 invalid template argument for 'boost::integral_constant', expected
 compile-time constant expression
 1>          z:\dev\projekte\boost\boost-
 dev\boost\boost\type_traits\integral_constant.hpp(18) : see declaration of
 'val'
 }}}

 Switching to std::tr1::is_convertible makes the code compile fine.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4530>
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