When setting the linker verbose, it indeed reports that it is searching log4cxx.lib. When setting fully verbose, it even reports *finding* symbols in log4cxx.lib with the file that references them. So indeed, the linker finds log4cxx.lib AND manages to find some of the symbols I use. Also, it seems that all the found symbols have a __thiscall declaration, while all the ones that are *not* found have a __stdcall declaration.
I have no idea whether this has any significance. regarding the __declspec thing, I noticed that the linker says the symbols it cannot find are __declspec(import), not __declspec(export). What are the differences between these two? Could it be that the "export" variations are in the log4cxx.lib file but cannot be matched to the "import" variation it's looking for? <venting frustration> Why is the Windows platform so poorly designed? None of those charades are necessary on the BSD architecture that MacOS X is built upon! </venting frustration> I am not sure what I can do next. I'll try to look for those symbols in the log4cxx source to check their declarations. Jean-Denis On May 7, 2010, at 12:02 , Fabian Jacquet wrote: > Mh, maybe those symbols are in the DLL but not in the lib. To be in the lib, > it must have __declspec(dllexport) when compiling. > log4cxx use this define to do this: > #if defined(LOG4CXX_STATIC) > #define LOG4CXX_EXPORT > // definitions used when building DLL > #elif defined(LOG4CXX) > #define LOG4CXX_EXPORT __declspec(dllexport) > #else > // definitions used when using DLL > #define LOG4CXX_EXPORT __declspec(dllimport) > #endif > > So, "LOG4CXX_EXPORT __declspec(dllexport)" when compiling log4cxx.dll > and > "LOG4CXX_EXPORT __declspec(dllimport)" when including log4cxx.h from your > project. > > If for some reason, LOG4CXX_STATIC is defined, it's possible that some > symbols are not exported. But I don't know how it's possible. > > If you don't use more than those 13 symbols maybe nothing is exported or > maybe the link don't use log4cxx.lib. > You can check the list of lib used by the linker like this: > Project properties>Linker>General>Show Progress = /VERBOSE:LIB > The linker will dump the lib list in the output window of visual studio when > compiling. Check that you have something like that: > 1> Searching [your directories]\log4cxx.lib: > > I don't know any tools to check symbols. I think you could check with > notepad, you can search about "getLogger" by example but if you find it, I > don't know if you can conclude that the symbol is right exported. If you > don't find it, I think the problem comes from the lib :-) > > On Fri, May 7, 2010 at 11:08, Jean-Denis Muys <jdm...@mac.com> wrote: > Thanks for answering. I wish the solution was that simple. I apologize for > not explicitly mentioning it, but my project is - I think - set up correctly. > > That is: > > - both the Debug and Release configurations mention log4cxx.lib in its > Linker>Input>Additional Dependencies > - both the Debug and Release configurations mention a *different* directory > in Linker>General>Additional Library Directories. They are different because > they point to the Debug version and the Relase version of loc4cxx > respectively (apache-log4cxx-0.10.0\projects\Debug and > apache-log4cxx-0.10.0\projects\Release) > > > Of course both configurations of log4cxx were previously built with no > failure (from its Visual Studio project). They were built in "DLL" mode as > explained on the log4cxx web site. While doing a static library version is on > my todo list, I'd rather solve the present issue first. > > At this point in time, I suppose the 13 missing symbols are present in the > Debug version of the log4cxx.lib stub library, but not in the Release > version. How can I verify this hypothesis? What could explain that? How can I > fix it? > > Another hypothesis might be that there is yet another dependency that needs > to be set in Release mode only. This seems less plausible though. And what > would it be? > > Again, thanks for you answer. Any other idea on how I could make progress on > this issue? > > Regards, > > Jean-Denis > > > On May 7, 2010, at 10:29 , Fabian Jacquet wrote: > >> Hi, >> >> The project configuration is different between debug and release. In debug >> you certainly added log4cxx.lib in the field "Linker/Input/Additional >> dependencies" but you have a drop-down which select the configuration, if >> you switch to release, I think you don't have log4cxx.lib in "Additional >> dependencies" . >> >> Don't forget to add the directory of this lib in the field >> "Linker/General/Additional Library Directories" >> >> log4cxx.lib is not really a static lib. It's only the interface to the dll >> class and functions. >> >> I hope it help you. >> >> On Fri, May 7, 2010 at 04:00, Jean-Denis Muys <jdm...@mac.com> wrote: >> Hi, >> >> I have a Visual Studio 2008 project using log4cxx that links (and runs) fine >> in Debug mode using the Debug version of log4cxx, but fails to link in >> Release mode using the release version of log4cxx. Here are the 13 undefined >> symbols: >> >> >> 1>------ Build started: Project: RepliKator04, Configuration: Release Win32 >> ------ >> 1>Linking... >> 1> Creating library >> z:\PCdev\RepliKator2004\RK_Demo_2004\plugins\RepliKator04.bundle\contents\windows\RepliKator04.lib >> and object >> z:\PCdev\RepliKator2004\RK_Demo_2004\plugins\RepliKator04.bundle\contents\windows\RepliKator04.exp >> 1>RKConnector.obj : error LNK2001: unresolved external symbol >> "__declspec(dllimport) public: static class >> log4cxx::helpers::ObjectPtrT<class log4cxx::Level> __stdcall >> log4cxx::Level::getTrace(void)" >> (__imp_?gettr...@level@log4cxx@@sg?av?$objectp...@vlevel@log4cxx@@@help...@2@XZ) >> [...] >> 1>RepliKator04 - 13 error(s), 0 warning(s) >> ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== >> >> >> As I am a Mac developer, not a Windows developer, I feel lost here. What can >> I do to fix that issue? I really don't get why those symbols would not be >> defined in Release mode. >> >> Note that my project is not an application, but a Plugin for a third party >> app. >> I link against the DLL version of log4cxx. I'd rather use a static library >> version, but I failed to build it so, and I could not find detailed >> instructions on the net to do it. >> >> So for the time being, I am mainly interested in understanding why these >> link-time errors occur, and in how to fix them. >> >> Thanks and regards. >> >> Jean-Denis >> >> > >
