id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
11541,Building with /Zc:wchar_t- on VC causes errors in boost::log since 1.59.0,dd0t@…,Andrey Semashev,"Boost 1.58.0 and earlier could be built successfully with '/Zc:wchar_t-' (no native wchar_t type) set. Since boost 1.59.0 this causes template errors in boost log. More specifically in code_conversion.hpp . I'm not quite clear on whether boost is actually interested in being able to build with this flag enabled in the first place, however I won't be the only one seeing this regression as it isn't unusual for this flag to be present in Windows projects. For example Qt was built with it throughout the 4.X series and most old systems with some MFC dependency set it at some point to retain binary compatibility.

Here one of the error messages from Visual Studio 2013 (VC12) for reference (looks pretty much the same for VC14):
{{{
.\boost/log/detail/code_conversion.hpp(114) : error C2784: 'boost::enable_if_c<boost::log::v2s_mt_nt5::aux::is_character_type<T>::value&&boost::log::v2s_mt_nt5::aux::is_character_type<TargetCharT>::value&&sizeof(SourceCharT)!=sizeof(TargetCharT),void>::type boost::log::v2s_mt_nt5::aux::code_convert(const SourceCharT *,size_t,std::basic_string<TargetCharT,TargetTraitsT,TargetAllocatorT> &,const std::locale &)' : could not deduce template argument for 'const SourceCharT *' from 'const std::wstring'
        .\boost/log/detail/code_conversion.hpp(93) : see declaration of 'boost::log::v2s_mt_nt5::aux::code_convert'
.\boost/log/detail/code_conversion.hpp(114) : error C2893: Failed to specialize function template 'boost::enable_if_c<boost::log::v2s_mt_nt5::aux::is_character_type<T>::value&&boost::log::v2s_mt_nt5::aux::is_character_type<TargetCharT>::value&&sizeof(SourceCharT)!=sizeof(TargetCharT),void>::type boost::log::v2s_mt_nt5::aux::code_convert(const std::basic_string<_Elem,_Traits,_Alloc> &,std::basic_string<TargetCharT,TargetTraitsT,TargetAllocatorT> &,const std::locale &)'
        With the following template arguments:
        'SourceCharT=wchar_t'
        'SourceTraitsT=std::char_traits<wchar_t>'
        'SourceAllocatorT=std::allocator<wchar_t>'
        'TargetCharT=char'
        'TargetTraitsT=std::char_traits<char>'
        'TargetAllocatorT=std::allocator<char>'
}}}
",Bugs,closed,To Be Determined,log,Boost 1.59.0,Regression,fixed,,