Bundling opencv as a static library gives thousands of undefined references

Question

I have a library that I am trying to link with openCV (and I think I did successfully) into one big dynamic library. I then try and add an executable and link everything together to test the library and I get 2000-3000 errors each saying

In function `________________`: undefined reference to `________`

some examples are:

/path/to/libs/libopencv_features2d.a(matchers.cpp.o): In function `cv::FlannBasedMatcher::read(cv::FileNode const&)':
matchers.cpp:(.text._ZN2cv17FlannBasedMatcher4readERKNS_8FileNodeE+0x227): undefined reference to `cv::flann::IndexParams::setAlgorithm(int)'

/path/to/libs/libopencv_videoio.a(cap_gstreamer.cpp.o)` In function `CvCapture_GStreamer::getProperty(int) const':
cap_gstreamer.cpp:(.text._ZNK19CvCapture_GStreamer11getPropertyEi+0x8b): undefined reference to `gst_element_query_position'

/path/to/lib/libopencv_core.a(stat.cpp.o): In function `cv::norm(cv::_InputArray const&, int, cv::_InputArray const&)':
stat.cpp:(.text._ZN2cv4normERKNS_11_InputArrayEiS2_+0x1d27): undefined reference to `ippicviNorm_L1_32f_C1MR'
stat.cpp:(.text._ZN2cv4normERKNS_11_InputArrayEiS2_+0x1dab): undefined reference to `ippicviNorm_L1_8u_C1MR'

My cmake file which runs:

project(SDK-build)
cmake_minimum_required(VERSION 2.8)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

set(MYLIB_SRC
    file1.cpp
    file2.cpp
    file3.cpp
)

add_library(gesture SHARED ${MYLIB_SRC})

cmake_policy(SET CMP0015 NEW)
link_directories(./opencvlib-wgstreamer)
set(OPENCV_LIBS
    libopencv_calib3d.a
    libopencv_core.a
    libopencv_features2d.a
    libopencv_highgui.a
    libopencv_imgcodecs.a
    libopencv_imgproc.a
    libopencv_ml.a
    libopencv_objdetect.a
    libopencv_photo.a
    libopencv_video.a
    libopencv_videoio.a
)

set(TEST_SRC
    test.cpp
)

add_executable(gesture_test ${TEST_SRC})

#build library
#target_link_libraries(gesture -Wl,-whole-archive ${OPENCV_LIBS} -Wl,--no-whole-archive)

#build library with executable
target_link_libraries(gesture_test gesture -Wl,-whole-archive ${OPENCV_LIBS} -Wl,--no-whole-archive)

When I use the first target_link_libraries, everything builds and make has no problem executing, but linking with the file with main() causes the massive confusion. Any suggestions I've been banging my head over this for hours. I also tried several combinations of compiling opencv, using both WITH_IPP=ON, WITH_IPP=OFF, and WITH_GSTREAMER_ON

score 0 · Answer 1 · edited May 23 '17 at 11:59

0

You have to specify the libraries in the correct order. See here for more information.

Edit I see you are using -Wl-whole-archive which I believe is an other possible way to fix the problem, so maybe I'm wrong

edited May 23 '17 at 11:59

Community

1
1

answered Mar 23 '16 at 23:05

Dimitri Merejkowsky

1,001
10
12

Yes your edit is right. So far I have learned that I need to link against `-lpthread`, I have forgotten about `libopencv_flann` and I have added `-Wl,--no-as-needed` before `${OpenCV_LIBS}` – wprins Mar 25 '16 at 13:32

Bundling opencv as a static library gives thousands of undefined references

1 Answers1