QT GStreamer Windows linker problems - c++

Question

I'm trying to compile and run the qml-sink example which is provided inside the gstreamer-good-plugin (QT Example). But currently I get a lot of undefined reference errors during the compile time. It seems that the linker does not link the libraries correctly.
I have checked the list of linked libraries and from my point of view all needed libs are listed.
E.g. gst_object_ref, gst_init, ... are undefined.
My setup:
Windows 10
Qt 5.11
Gstreamer 1.0
Gstremer devel 1.0
Gstreamer plugin good
Installed GStreamer version from here: GStreamer Download => gstreamer-1.0-devel-x86_64-1.14.3.msi and gstreamer-1.0-x86_64-1.14.3.msi
Can anyone please help me, how I can solve this problem?
Errortrace:
"C:\Program Files\CMake\bin\cmake.exe" --build . --target all
"C:\Program Files\CMake\bin\cmake.exe" -HC:\gst-plugins-good-1.14.4\tests\examples\qt\qmlsink -BC:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe --check-build-system CMakeFiles\Makefile.cmake 0
"C:\Program Files\CMake\bin\cmake.exe" -E cmake_progress_start C:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe\CMakeFiles C:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe\CMakeFiles\progress.marks
D:/Qt/Tools/mingw530_32/bin/mingw32-make.exe -f CMakeFiles\Makefile2 all
mingw32-make.exe[1]: Entering directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
D:/Qt/Tools/mingw530_32/bin/mingw32-make.exe -f CMakeFiles\qml-example.dir\build.make CMakeFiles/qml-example.dir/depend
mingw32-make.exe[2]: Entering directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
"C:\Program Files\CMake\bin\cmake.exe" -E cmake_depends "MinGW Makefiles"
C:\gst-plugins-good-1.14.4\tests\examples\qt\qmlsink C:\gst-plugins-good-1.14.4\tests\examples\qt\qmlsink C:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe
C:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe C:\gst-plugins-good-1.14.4\tests\examples\qt\build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe\CMakeFiles\qml-example.dir\DependInfo.cmake --color=
mingw32-make.exe[2]: Leaving directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
D:/Qt/Tools/mingw530_32/bin/mingw32-make.exe -f CMakeFiles\qml-example.dir\build.make CMakeFiles/qml-example.dir/build
mingw32-make.exe[2]: Entering directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
[ 25%] Linking CXX executable qml-example.exe
"C:\Program Files\CMake\bin\cmake.exe" -E cmake_link_script CMakeFiles\qml-example.dir\link.txt --verbose=1
"C:\Program Files\CMake\bin\cmake.exe" -E remove -f CMakeFiles\qml-example.dir/objects.a
D:\Qt\Tools\mingw530_32\bin\ar.exe cr CMakeFiles\qml-example.dir/objects.a #CMakeFiles\qml-example.dir\objects1.rsp
D:\Qt\Tools\mingw530_32\bin\g++.exe -Wl,--whole-archive CMakeFiles\qml-example.dir/objects.a -Wl,--no-whole-archive -o qml-example.exe -Wl,--out-implib,libqml-example.dll.a -Wl,--major-image-version,0,--minor-image-version,0
#CMakeFiles\qml-example.dir\linklibs.rsp
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x2b): undefined reference to `gst_object_ref'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x87): undefined reference to `gst_object_unref'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0xa7): undefined reference to `operator delete(void*)'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0xc8): undefined reference to `operator delete(void*)'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0xf3): undefined reference to `gst_element_set_state'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x150): undefined reference to `gst_init'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x17d): undefined reference to `gst_pipeline_new'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x194): undefined reference to `gst_element_factory_make'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x1ab): undefined reference to `gst_element_factory_make'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x1c2): undefined reference to `gst_element_factory_make'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x203): undefined reference to `g_assertion_message_expr'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x208): undefined reference to `gst_bin_get_type'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x217): undefined reference to `g_type_check_instance_cast'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x23e): undefined reference to `gst_bin_add_many'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x25f): undefined reference to `gst_element_link_many'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x37f): undefined reference to `g_assertion_message_expr'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x3a1): undefined reference to `g_object_set'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x3ad): undefined reference to `operator new(unsigned int)'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x3f6): undefined reference to `gst_element_set_state'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x401): undefined reference to `gst_object_unref'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x41e): undefined reference to `gst_deinit'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text+0x467): undefined reference to `operator delete(void*)'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text$_ZN5QListIP7QObjectE13detach_helperEi[__ZN5QListIP7QObjectE13detach_helperEi]+0x8c): undefined reference to `__cxa_begin_catch'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text$_ZN5QListIP7QObjectE13detach_helperEi[__ZN5QListIP7QObjectE13detach_helperEi]+0xa3): undefined reference to `__cxa_rethrow'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.text$_ZN5QListIP7QObjectE13detach_helperEi[__ZN5QListIP7QObjectE13detach_helperEi]+0xaa): undefined reference to `__cxa_end_catch'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.rdata$_ZTI10SetPlaying[__ZTI10SetPlaying]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.rdata$_ZTI9QRunnable[__ZTI9QRunnable]+0x0): undefined reference to `vtable for __cxxabiv1::__class_type_info'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.eh_frame+0x13): undefined reference to `__gxx_personality_v0'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.eh_frame$_ZN5QListIP7QObjectED1Ev+0x13): undefined reference to `__gxx_personality_v0'
CMakeFiles\qml-example.dir/objects.a(main.cpp.obj):main.cpp:(.eh_frame$_ZN5QListIP7QObjectE13detach_helperEi+0x13): undefined reference to `__gxx_personality_v0'
CMakeFiles\qml-example.dir/objects.a(qrc_qml.cpp.obj):qrc_qml.cpp:(.eh_frame+0x8b): undefined reference to `__gxx_personality_v0'
collect2.exe: error: ld returned 1 exit status
mingw32-make.exe[2]: *** [qml-example.exe] Error 1
mingw32-make.exe[1]: *** [CMakeFiles/qml-example.dir/all] Error 2
CMakeFiles\qml-example.dir\build.make:112: recipe for target 'qml-example.exe' failed
mingw32-make.exe[2]: Leaving directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
CMakeFiles\Makefile2:66: recipe for target 'CMakeFiles/qml-example.dir/all' failed
mingw32-make.exe[1]: Leaving directory 'C:/gst-plugins-good-1.14.4/tests/examples/qt/build-qmlsink-Desktop_Qt_5_11_1_MinGW_32bit-Vorgabe'
Makefile:82: recipe for target 'all' failed
mingw32-make.exe: *** [all] Error 2

Answer 1

It looks like you're building for windows. The only way I've compiled the qml plugin on windows is using qmake using the provided .pro file. My experiments with compiling using the mingw toolchain provided by Qt were unsuccessful due to mismatching C++ ABI's between GStreamer and Qt. I ended up using MSVC/Visual Studio for compiling instead.
The undefined references to g_/gst_ probably means you don't have pkg-config setup correctly on your system. pkg-config.exe --modversion gstreamer-1.0 Should output the version of GStreamer you installed.
Where did you download GStreamer from? What GStreamer version exactly? Did you download binaries or did you compile it yourself?