Ubuntu编译opencv3.4.5报错undefined reference to `cv::cuda::SURF

报错信息：

CMakeFiles/example_gpu_surf_keypoint_matcher.dir/surf_keypoint_matcher.cpp.o: In function `main':
surf_keypoint_matcher.cpp:(.text.startup.main+0x352): undefined reference to `cv::cuda::SURF_CUDA::SURF_CUDA()'
surf_keypoint_matcher.cpp:(.text.startup.main+0x579): undefined reference to `cv::cuda::SURF_CUDA::operator()(cv::cuda::GpuMat const&, cv::cuda::GpuMat const&, cv::cuda::GpuMat&, cv::cuda::GpuMat&, bool)'
surf_keypoint_matcher.cpp:(.text.startup.main+0x60d): undefined reference to `cv::cuda::SURF_CUDA::operator()(cv::cuda::GpuMat const&, cv::cuda::GpuMat const&, cv::cuda::GpuMat&, cv::cuda::GpuMat&, bool)'
surf_keypoint_matcher.cpp:(.text.startup.main+0x6af): undefined reference to `cv::cuda::SURF_CUDA::defaultNorm() const'
surf_keypoint_matcher.cpp:(.text.startup.main+0x7ca): undefined reference to `cv::cuda::SURF_CUDA::downloadKeypoints(cv::cuda::GpuMat const&, std::vector >&)'
surf_keypoint_matcher.cpp:(.text.startup.main+0x7ea): undefined reference to `cv::cuda::SURF_CUDA::downloadKeypoints(cv::cuda::GpuMat const&, std::vector >&)'
surf_keypoint_matcher.cpp:(.text.startup.main+0x800): undefined reference to `cv::cuda::SURF_CUDA::downloadDescriptors(cv::cuda::GpuMat const&, std::vector >&)'
surf_keypoint_matcher.cpp:(.text.startup.main+0x812): undefined reference to `cv::cuda::SURF_CUDA::downloadDescriptors(cv::cuda::GpuMat const&, std::vector >&)'
collect2: error: ld returned 1 exit status
samples/gpu/CMakeFiles/example_gpu_surf_keypoint_matcher.dir/build.make:132: recipe for target 'bin/example_gpu_surf_keypoint_matcher' failed
make[2]: *** [bin/example_gpu_surf_keypoint_matcher] Error 1

解决方案：

修改build文件夹下文件内容，具体路径为：

./build/samples/gpu/CMakeFiles/example_gpu_surf_keypoint_matcher.dir/link.txt 

在

CMakeFiles/example_gpu_surf_keypoint_matcher.dir/surf_keypoint_matcher.cpp.o

后面添加

../../modules/xfeatures2d/CMakeFiles/opencv_xfeatures2d.dir/src/surf.cuda.cpp.o ../../modules/xfeatures2d/CMakeFiles/cuda_compile_1.dir/src/cuda/cuda_compile_1_generated_surf.cu.o

建议改成绝对路径。

问题解决