not able to include non free OpenCV 3.0

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I'm trying to use SURF/SIFT in the alpha version of the OpenCV 3.0. I already checked these links 1,2,3,4 without being able to solve the error occured when I include "opencv2/xfeatures2d/nonfree.hpp".

I debrief below what I've tried:

1. I knew that SURF/SIFT are now in a separate module and we should load it upon builiding OpenCV to make it work so I got the module repository from this link and I built OpenCV using the following command :

cmake -DOPENCV_EXTRA_MODULES_PATH=/home/opencvContrib/modules ..

1. Here is a text extracted from the results displayed after running this command:

OpenCV modules:

1. To be built: core flann imgproc imgcodecs videoio highgui features2d calib3d ml objdetect photo video shape stitching superres ts videostab
2. Disabled: world
3. Disabled by dependency: -
4. Unavailable: androidcamera cuda cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaoptflow cudastereo cudawarping cudev java python2 python3 viz

It seems to me weird to have these modules because they are just the modules in the openCV repository and none of them are from the module repository so I would assume it as a reason for my problem.

Any idea on what's going on?