[Boost-bugs] [Boost C++ Libraries] #2409: boost::optional (boost-1.36.0) fails to compile on MSVS 9.0 with struct member alignment being set to 1 byte

Subject: [Boost-bugs] [Boost C++ Libraries] #2409: boost::optional (boost-1.36.0) fails to compile on MSVS 9.0 with struct member alignment being set to 1 byte
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-10-13 12:10:49

#2409: boost::optional (boost-1.36.0) fails to compile on MSVS 9.0 with struct
member alignment being set to 1 byte
----------------------------------+-----------------------------------------
 Reporter:  slava_at_[hidden]  |       Owner:  fcacciola 
     Type:  Bugs                  |      Status:  new       
Milestone:  Boost 1.37.0          |   Component:  optional  
  Version:  Boost 1.36.0          |    Severity:  Regression
 Keywords:                        |  
----------------------------------+-----------------------------------------
 When I try to compile the following code with MSVS 9.0 and boost-1.36.0
 with struct member alignment being set to 1 or 2 bytes, it fails with
 boost::STATIC_ASSERTION_FAILURE:
 {{{
 #include <boost/optional.hpp>

 boost::optional<int> test_func(int i) {
         if(i) return boost::optional<int>(1234);
         else return boost::optional<int>();
 }


 int main(int argc, char* argv[])
 {
         test_func(1);
         return 0;
 }
 }}}

 The errors are:
 {{{
 d:\users\slava\etap\external\boost\boost\type_traits\type_with_alignment.hpp(206)
 : error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE<x>'
 1>        with
 1>        [
 1>            x=false
 1>        ]
 1>
 d:\users\slava\etap\external\boost\boost\type_traits\type_with_alignment.hpp(218)
 : see reference to class template instantiation
 'boost::detail::type_with_alignment_imp<Align>' being compiled
 1>        with
 1>        [
 1>            Align=4
 1>        ]
 1>
 d:\users\slava\etap\external\boost\boost\optional\optional.hpp(112) : see
 reference to class template instantiation
 'boost::type_with_alignment<Align>' being compiled
 1>        with
 1>        [
 1>            Align=4
 1>        ]
 1>
 d:\users\slava\etap\external\boost\boost\optional\optional.hpp(113) : see
 reference to class template instantiation
 'boost::optional_detail::aligned_storage<T>::dummy_u' being compiled
 1>        with
 1>        [
 1>            T=int
 1>        ]
 1>
 d:\users\slava\etap\external\boost\boost\optional\optional.hpp(448) : see
 reference to class template instantiation
 'boost::optional_detail::aligned_storage<T>' being compiled
 1>        with
 1>        [
 1>            T=int
 1>        ]
 1>
 d:\users\slava\etap\external\boost\boost\optional\optional.hpp(455) : see
 reference to class template instantiation
 'boost::optional_detail::optional_base<T>' being compiled
 1>        with
 1>        [
 1>            T=int
 1>        ]
 1>        d:\users\slava\test\test.cpp(8) : see reference to class
 template instantiation 'boost::optional<T>' being compiled
 1>        with
 1>        [
 1>            T=int
 1>        ]
 1>d:\users\slava\etap\external\boost\boost\type_traits\type_with_alignment.hpp(207)
 : error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE<x>'
 1>        with
 1>        [
 1>            x=false
 1>        ]
 }}}

 Setting struct member alignment to 4 or more bytes solves the problem. The
 same code compiles well with any alignment value with boost-1.35.

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/2409>
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