Error adding OpenCV 3.0 OpenCL UMat

I'm trying to use the OpenCV API (3.0 beta) for OpenCL, but I have strange compilation errors for simple operations (at least for addition and subtraction).

Here's some sample code:

#include <opencv2/core.hpp>
#include <opencv2/core/ocl.hpp>
#include <iostream>

using namespace std;
using namespace cv;

Mat temp;

int main() {

    // activating opencl
    ocl::setUseOpenCL(true);

    UMat mat1 = UMat::ones(3,4,CV_32F);
    UMat mat2 = UMat::ones(3,4,CV_32F);
    UMat mat3;
    mat3 = mat1 + mat2;
    mat3.copyTo(temp);
    cout << "mat3 = " << endl << " " << temp << endl << endl;
}

      

        
        
        
      

    

I am getting this error:

/home/matthieu/git/stages/singapore/opencv_perf_tests/opencl_test.cpp: In function ‘int main()’:
/home/matthieu/git/stages/singapore/opencv_perf_tests/opencl_test.cpp:19:17: error: no match for ‘operator+’ (operand types are ‘cv::UMat’ and ‘cv::UMat’)
    mat3 = mat1 + mat2;
                ^

      

        
        
        
      

    

It's the same with subtraction. I cannot find anyone with the same error. Am I doing something wrong?