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c++visual-studio-2012vlcstatic-linkinglibvlc

VLC Api with C++ - linker error for .lib (even when I've added it to my VC++ project)

I wanted to compile the sample C++ program that uses VLC Api, according to the https://wiki.videolan.org/LibVLC_Tutorial/, with my Visual Studio 2012 on Windows 7 x64 (I work with x86 anyway).

In order to obtain a .lib file, I've followed: https://wiki.videolan.org/GenerateLibFromDll/. I had some problems at the start, but finally I got (I've noticed the warnings): enter image description here

And I do have my libvlc.lib created. I've moved it to the folder with my main.cpp, added the path to Project -> VC++ Directories -> Library directories as well as added the .lib file with Add -> existing item. I also added the Project -> VC++ Directories -> Include Directories so it points to ...vlc-2.1.5\include.

I run the clean, rebuild all on my empty solution.

Unfortunately I got the errors:

1>------ Rebuild All started: Project: Project1, Configuration: Debug Win32 ------
1>  Source.cpp
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_new referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_release referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_new_location referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_release referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_player_new_from_media referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_player_release referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_player_play referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol _libvlc_media_player_stop referenced in function _main
1>...\Project1\Debug\Project1.exe : fatal error LNK1120: 8 unresolved externals

Which looks like either something is wrong with my .lib or its somehow it's not connected in a right way. The compilation works fine, the linking fails.

The full source code of the only .cpp file in project is an exact copy of the tutorial posted on videolan.org: http://pastebin.com/5gfFVFZd

edit:

According to @user1 comment, I've corrected the dumpbin command (in the screen shot, "libvlc.dill" should be "libvlc.dll"). That was indeed one problem. After the change, I got much more warnings (all of the same type as before, 277 together) and much bigger .def file (15MB, progress). But the output .lib file is exact same size (1.48MB - it's very small .lib) and the linker error with it prevails. So I guess there's still something wrong with the .lib creation.

The .def file: http://pastebin.com/E81s6dnh The last lines make me feel uncomfortable:

    256   FF 00001CF0 libvlc_vprinterr
    257  100 00001790 libvlc_wait
LINK : fatal error LNK1328: missing string table
Solution

  • Check dumpbin command in the screen shot,

    "libvlc.dill" should be "libvlc.dll"

    Generally speaking, when all inputs to linker are correct & yet if linker complains then I would look at some lib import #defines specifically. Sometimes, .lib can't just be imported without defining some #DEFINE in the linker input settings which allows the lib to be imported. e.g. IMPORT_X_LIB. Do you have any such import lib #define defined for vlc lib. if yes, you must add those in linker input.