Arch Linux：用 cuda 建構 opencv 的問題；libopencv_core.so.3.4.0：未定義對“cblas_dgemm”的引用

我目前正在嘗試在我的 Arch linux 電腦上建構一個具有 cuda 的 opencv 版本。為此，我使用opencv-cuda-git作為基礎版本。此外，我修改了 PKGBUILD 並添加了其他標誌以進一步使 opencv 適應我的系統。

但是，每次我執行建構過程（makepkg csri）時，它都會失敗並顯示以下錯誤消息：

[ 16%] Building CXX object modules/hdf/CMakeFiles/example_hdf_create_groups.dir/samples/create_groups.cpp.o
cd /home/tobias/builds/opencv-cuda-git/src/opencv/build/modules/hdf && /usr/bin/cmake -E cmake_link_script CMakeFiles/example_hdf_create_groups.dir/link.txt --verbose=1
/bin/g++-6  -std=c++11   -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffast-math -ffunction-sections -fdata-sections  -msse -msse2 -fvisibility=hidden -fvisibility-inlines-hidden -Wno-invalid-offsetof -O3 -DNDEBUG  -DNDEBUG  -Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now  -Wl,--gc-sections   -rdynamic CMakeFiles/example_hdf_create_groups.dir/samples/create_groups.cpp.o  -o ../../bin/example_hdf_create_groups  -L/opt/cuda/lib64 ../../lib/libopencv_hdf.so.3.4.0 ../../lib/libopencv_highgui.so.3.4.0 ../../lib/libopencv_videoio.so.3.4.0 ../../lib/libopencv_imgcodecs.so.3.4.0 ../../lib/libopencv_imgproc.so.3.4.0 ../../lib/libopencv_core.so.3.4.0 ../../lib/libopencv_cudev.so.3.4.0 
../../lib/libopencv_core.so.3.4.0: undefined reference to `cblas_zgemm'
../../lib/libopencv_core.so.3.4.0: undefined reference to `cblas_sgemm'
../../lib/libopencv_core.so.3.4.0: undefined reference to `cblas_dgemm'
../../lib/libopencv_core.so.3.4.0: undefined reference to `cblas_cgemm'
make[2]: *** [modules/hdf/CMakeFiles/example_hdf_create_groups.dir/build.make:102: bin/example_hdf_create_groups] Error 1
make[2]: Leaving directory '/home/tobias/builds/opencv-cuda-git/src/opencv/build'
make[1]: *** [CMakeFiles/Makefile2:2523: modules/hdf/CMakeFiles/example_hdf_create_groups.dir/all] Error 2
make[1]: Leaving directory '/home/tobias/builds/opencv-cuda-git/src/opencv/build'
make: *** [Makefile:163: all] Error 2

我之前的搜尋表明，由於與 cublas 的連結錯誤，可能會發生此錯誤。因此，我嘗試將**-L/opt/cuda/lib64和-lcublas 添加**到CMAKE_CXX_FLAGS。那根本沒有區別。

另一個部落格的建議包含使用 gcc-6 而不是 g++-6。然而，這會產生另一個錯誤：

[ 16%] Linking CXX executable ../../bin/example_hdf_create_groups
cd /home/tobias/builds/opencv-cuda-git/src/opencv/build/modules/hdf && /usr/bin/cmake -E cmake_link_script CMakeFiles/example_hdf_create_groups.dir/link.txt --verbose=1
/bin/gcc-6  -std=c++11   -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -Wno-long-long -pthread -fomit-frame-pointer -ffast-math -ffunction-sections -fdata-sections  -msse -msse2 -fvisibility=hidden -fvisibility-inlines-hidden -Wno-invalid-offsetof -O3 -DNDEBUG  -DNDEBUG  -Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now  -Wl,--gc-sections   -rdynamic CMakeFiles/example_hdf_create_groups.dir/samples/create_groups.cpp.o  -o ../../bin/example_hdf_create_groups  -L/opt/cuda/lib64 ../../lib/libopencv_hdf.so.3.4.0 ../../lib/libopencv_highgui.so.3.4.0 ../../lib/libopencv_videoio.so.3.4.0 ../../lib/libopencv_imgcodecs.so.3.4.0 ../../lib/libopencv_imgproc.so.3.4.0 ../../lib/libopencv_core.so.3.4.0 ../../lib/libopencv_cudev.so.3.4.0     
ld: CMakeFiles/example_hdf_create_groups.dir/samples/create_groups.cpp.o: undefined reference to symbol '_ZNSt8ios_base4InitD1Ev@@GLIBCXX_3.4'
/usr/lib/libstdc++.so.6: error adding symbols: DSO missing from command line
make[2]: *** [modules/hdf/CMakeFiles/example_hdf_create_groups.dir/build.make:102: bin/example_hdf_create_groups] Error 1
make[2]: Leaving directory '/home/tobias/builds/opencv-cuda-git/src/opencv/build'
make[1]: *** [CMakeFiles/Makefile2:2523: modules/hdf/CMakeFiles/example_hdf_create_groups.dir/all] Error 2
make[1]: Leaving directory '/home/tobias/builds/opencv-cuda-git/src/opencv/build'
make: *** [Makefile:163: all] Error 2

建構過程的整個輸出和自定義的 PKGBUILD 文件可以在這裡找到

Cuda 版本 9，nvidia-smi 的輸出：

Sun Jan 14 14:44:13 2018       
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 387.34                 Driver Version: 387.34                    |        |-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|===============================+======================+======================|
|   0  GeForce GTX 780 Ti  Off  | 00000000:01:00.0 N/A |                  N/A |
| 32%   27C    P8    N/A /  N/A |    624MiB /  3017MiB |     N/A      Default |
+-------------------------------+----------------------+----------------------+

+-----------------------------------------------------------------------------+
| Processes:                                                       GPU Memory |
|  GPU       PID   Type   Process name                             Usage      |
|=============================================================================|
|    0                    Not Supported                                       |
+-----------------------------------------------------------------------------+

好的，關閉問題：

問題是 opencv 既需要Lapack正常blas，cblas也需要使用ceres-solver. 但是，opencv build only linkscublas顯然缺乏對 cblas 一些所需功能的支持。

此問題的一種解決方案是cblas通過添加 CMAKE_EXE_LINKER_FLAGS=-lcblas到cmakePKGBUILD 文件中的呼叫來手動連結。

cublas通過在強制支持下手動建構所有依賴項，可能完全規避這個問題。但是，這很乏味並且並不總是可能的，因為cublas它只是一個部分埠。

再次感謝Philippos，他幫助我縮小了問題範圍。

引用自：https://unix.stackexchange.com/questions/417032