# Issues with crosscompiling opencvsharp: "Error adding symbols; File in wrong format" for .so files
**URL:** https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352
**Category:** Uncategorized
**Tags:** arm, build, csharp
**Created:** [May 29, 2023, 12:56pm UTC](https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352 "2023-05-29T12:56:53Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@rash\_dev](https://forum.opencv.org/u/rash_dev)
#### Post date: [May 29, 2023, 12:56pm UTC](https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352/1 "2023-05-29T12:56:53Z")
I am having this problem when trying to cross compile opencvsharp after successfully building and making opencv (for linux-arm64). I cmake opencvsharp with no problems but when I make I get this “Error adding Symbols; File in wrong format” error:
```auto
Scanning dependencies of target OpenCvSharpExtern
[2%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/bgsegm.cpp.o
[8%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/aruco.cpp.o
[8%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/calib3d.cpp.o
[11%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/core.cpp.o
[14%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/flann.cpp.o
[17%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/dnn.cpp.o
[20%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/img_hash.cpp.o
[23%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/cuda.cpp.o
[26%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/line_descriptor.cpp.o
[29%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/imgcodecs.cpp.o
[32%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/ml.cpp.o
[35%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/features2d.cpp.o
[38%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/dnn_superres.cpp.o
[41%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/quality.cpp.o
[44%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/tracking.cpp.o
[50%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/xfeatures2d.cpp.o
[55%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/highgui.cpp.o
[50%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/imgproc.cpp.o
[52%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/ximgproc.cpp.o
[61%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/text.cpp.o
[64%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/stitching.cpp.o
[67%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/wechat_qrcode.cpp.o
[67%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/video.cpp.o
[73%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/objdetect.cpp.o
[73%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/xphoto.cpp.o
[76%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/std_string.cpp.o
[82%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/shape.cpp.o
[79%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/videoio.cpp.o
[97%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/face.cpp.o
[97%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/optflow.cpp.o
[85%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/photo.cpp.o
[97%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/std_vector.cpp.o
[88%] Building CXX object OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/superres.cpp.o
[100%] Linking CXX shared library libOpenCvSharpExtern.so
/media/data/[CENSORED]/dotnet/lib/opencv/opencv/platforms/linux/build/lib/libopencv_gapi.so.4.7.0: error adding symbols: File in wrong format
collect2: error: ld returned 1 exit status
OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/build.make:978: recipe for target 'OpenCvSharpExtern/libOpenCvSharpExtern.so' failed
make[2]: *** [OpenCvSharpExtern/libOpenCvSharpExtern.so] Error 1
CMakeFiles/Makefile2:85: recipe for target 'OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/all' failed
make[1]: *** [OpenCvSharpExtern/CMakeFiles/OpenCvSharpExtern.dir/all] Error 2
Makefile:129: recipe for target 'all' failed
make: *** [all] Error 2
Error adding Symbols; File in wrong format
```
for libopencv\_gapi.so.4.7.0
and I built fresh from master branches of opencv, opencv\_contrib and opencvsharp… please help
---
### Author:  [@crackwitz](https://forum.opencv.org/u/crackwitz)
#### Post date: [May 29, 2023, 3:05pm UTC](https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352/2 "2023-05-29T15:05:50Z")
that’s not “the same problem” though. I’ve split your post off into a new thread.
“opencvsharp” is a **separate project** unrelated to OpenCV. you should contact the maintainers of that project.
---
### Author:  [@berak](https://forum.opencv.org/u/berak)
#### Post date: [May 30, 2023, 5:24am UTC](https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352/3 "2023-05-30T05:24:12Z")
when doing major changes to the build process, as changing target-arch or cc-chain, – clean the build folder ! (and start all over with cmake)
---
### Author:  [@rash\_dev](https://forum.opencv.org/u/rash_dev)
#### Post date: [May 30, 2023, 5:39am UTC](https://forum.opencv.org/t/issues-with-crosscompiling-opencvsharp-error-adding-symbols-file-in-wrong-format-for-so-files/13352/4 "2023-05-30T05:39:38Z")
I followed this practice, it does not fix the problem unfortunately.