Re: [Boost-users] bjam does not find *.lib file

Subject: Re: [Boost-users] bjam does not find *.lib file
From: Ronny Herzog (herzog_at_[hidden])
Date: 2013-03-04 10:40:55

Thank you, Juergen,

there is a switch in the pugixml.hpp for the dll export. When I switch 
this on, it does not complain about not-finding the *.lib. I am just 
wondering, because the compilation worked some months ago.

Anyway, I get another strange error. It says

error LNK2019: unresolved external symbol [...]

The linker cannot resolve a function which is defined in the same file:
pugixml.cpp:
<code>
//[...]
     // Writer interface for node printing (see xml_node::print)
     class PUGIXML_CLASS xml_writer
     {
     public:
         virtual ~xml_writer() {}

         // Write memory chunk into stream/file/whatever
         virtual void write(const void* data, size_t size) = 0;
     };

     // xml_writer implementation for FILE*
     class PUGIXML_CLASS xml_writer_file: public xml_writer
     {
     public:
         // Construct writer from a FILE* object; void* is used to avoid 
header dependencies on stdio
         xml_writer_file(void* file);

         virtual void write(const void* data, size_t size);

     private:
         void* file;
     };

     #ifndef PUGIXML_NO_STL
     // xml_writer implementation for streams
     class PUGIXML_CLASS xml_writer_stream: public xml_writer
     {
     public:
         // Construct writer from an output stream object
         xml_writer_stream(std::basic_ostream<char, 
std::char_traits<char> >& stream);
         xml_writer_stream(std::basic_ostream<wchar_t, 
std::char_traits<wchar_t> >& stream);

         virtual void write(const void* data, size_t size);

     private:
         std::basic_ostream<char, std::char_traits<char> >* narrow_stream;
         std::basic_ostream<wchar_t, std::char_traits<wchar_t> >* 
wide_stream;
     };
     #endif
//[...]
</code>

and pugixml.hpp:
<code>
//[...]
namespace pugi
{
     PUGI__FN xml_writer_file::xml_writer_file(void* file_): file(file_)
     {
     }

     PUGI__FN void xml_writer_file::write(const void* data, size_t size)
     {
         size_t result = fwrite(data, 1, size, static_cast<FILE*>(file));
         (void)!result; // unfortunately we can't do proper error 
handling here
     }

#ifndef PUGIXML_NO_STL
     PUGI__FN 
xml_writer_stream::xml_writer_stream(std::basic_ostream<char, 
std::char_traits<char> >& stream): narrow_stream(&stream), wide_stream(0)
     {
     }

     PUGI__FN 
xml_writer_stream::xml_writer_stream(std::basic_ostream<wchar_t, 
std::char_traits<wchar_t> >& stream): narrow_stream(0), wide_stream(&stream)
     {
     }

     PUGI__FN void xml_writer_stream::write(const void* data, size_t size)
     {
         if (narrow_stream)
         {
             assert(!wide_stream);
             narrow_stream->write(reinterpret_cast<const char*>(data), 
static_cast<std::streamsize>(size));
         }
         else
         {
             assert(wide_stream);
             assert(size % sizeof(wchar_t) == 0);

             wide_stream->write(reinterpret_cast<const wchar_t*>(data), 
static_cast<std::streamsize>(size / sizeof(wchar_t)));
         }
     }
#endif
//[...]
</code>

Thanks for the help!
Ronny

Am 3/4/2013 2:40 PM, schrieb Jürgen Hunold:
> Hi Ronny,
>        On Monday, 4. March 2013 14:28:58 Ronny Herzog wrote:
>        
>> Dear all,
>>        I have troubles to compile because bjam does not find a *.lib file
>>        which I
>>        would expect to be there. I am on Windows 7 with Boost 1.50.0 and
>>        visual
>>        studio 10.
>>        It complains:
>>        LINK : fatal error LNK1181: cannot open input file
>>        '..\boost-build\additional\msvc-10.0\release\address-model-64\threading-mult
>> i\pugixml.lib'
>>        Which is true, the compiler does not build a pugixml.lib. I
>>        don't understand why it is not build, since I am building a *.dll.
>>        I would
>>        appriciate any help, because I have no clue where I should look
>>        for the
>>        problem.
>>        
> That
>        is most probably the classical bug that the msvc link.exe does not
>        generate a .lib export library when no visible symbols are
>        available. Do you export your symbols from "pugixml.cpp"
>        via "dllexport/import"? Your Jamfile for
>        "pugixml" seems to contain no controlling define for
>        that.
>        Yours,
>        Jürgen
>