What can I resolve this error?
-- Found VTK ver. 6.2.0 (usefile: /usr/lib/cmake/vtk-6.2/UseVTK.cmake) CMake Error at cmake/OpenCVModule.cmake:268 (message): The directory /home/gregory/opencv/modules is observed for OpenCV modules second time. Call Stack (most recent call first): modules/CMakeLists.txt:7 (ocv_glob_modules)
Ubuntu 16.04, opencv-3.2.0, cmake 3.5.1