在编译OpenCV和opencv_contrib源码时，提示

CMake Error at cmake/OpenCVModule.cmake:356 (_glob_locations):
  Syntax error in cmake code at

    F:/WorkSpace/opencv-4.8.0/cmake/OpenCVModule.cmake:356

  when parsing string

    F:\WorkSpace\opencv_contrib-4.8.0\modules

  Invalid character escape '\W'.
Call Stack (most recent call first):
  cmake/OpenCVModule.cmake:408 (ocv_glob_modules)
  CMakeLists.txt:967 (ocv_register_modules)

提示“Invalid character escape '\W'.”错误，经查询，原来是OPENCV_EXTRA_MODULES_PATH的路径斜杠不对，默认的Windows路径是用反斜杠“\"

但CMake要用正斜杠”/" 

 将路径的斜杠改为“/”即可。