Issue running mingw32-make in build folder

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after running cmake on the source folder, then I ran mingw32-make on the build folder and this was the error output. Please I need a solutuion.

Building CXX object modules/video/CMakeFiles/opencv_video.dir/src/dis_flow.cpp.obj
C:\opencv\sources\modules\video\src\dis_flow.cpp:54:1: error: expected class-name before '{' token
 {
 ^
C:\opencv\sources\modules\video\src\dis_flow.cpp:136:16: error: 'VariationalRefinement' was not declared in this scope
     vector<Ptr<VariationalRefinement> > variational_refinement_processors;
                ^~~~~~~~~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:136:16: note: suggested alternative: 'setVariationalRefinementGamma'
     vector<Ptr<VariationalRefinement> > variational_refinement_processors;
                ^~~~~~~~~~~~~~~~~~~~~
                setVariationalRefinementGamma
C:\opencv\sources\modules\video\src\dis_flow.cpp:136:37: error: template argument 1 is invalid
     vector<Ptr<VariationalRefinement> > variational_refinement_processors;
                                     ^
C:\opencv\sources\modules\video\src\dis_flow.cpp:136:39: error: template argument 1 is invalid
     vector<Ptr<VariationalRefinement> > variational_refinement_processors;
                                       ^
C:\opencv\sources\modules\video\src\dis_flow.cpp:136:39: error: template argument 2 is invalid
C:\opencv\sources\modules\video\src\dis_flow.cpp:58:10: error: 'void cv::DISOpticalFlowImpl::calc(cv::InputArray, cv::InputArray, cv::InputOutputArray)' marked 'override', but does not override
     void calc(InputArray I0, InputArray I1, InputOutputArray flow) CV_OVERRIDE;
          ^~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:59:10: error: 'void cv::DISOpticalFlowImpl::collectGarbage()' marked 'override', but does not override
     void collectGarbage() CV_OVERRIDE;
          ^~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:79:9: error: 'int cv::DISOpticalFlowImpl::getFinestScale() const' marked 'override', but does not override
     int getFinestScale() const CV_OVERRIDE { return finest_scale; }
         ^~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:80:10: error: 'void cv::DISOpticalFlowImpl::setFinestScale(int)' marked 'override', but does not override
     void setFinestScale(int val) CV_OVERRIDE { finest_scale = val; }
          ^~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:81:9: error: 'int cv::DISOpticalFlowImpl::getPatchSize() const' marked 'override', but does not override
     int getPatchSize() const CV_OVERRIDE { return patch_size; }
         ^~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:82:10: error: 'void cv::DISOpticalFlowImpl::setPatchSize(int)' marked 'override', but does not override
     void setPatchSize(int val) CV_OVERRIDE { patch_size = val; }
          ^~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:83:9: error: 'int cv::DISOpticalFlowImpl::getPatchStride() const' marked 'override', but does not override
     int getPatchStride() const CV_OVERRIDE { return patch_stride; }
         ^~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:84:10: error: 'void cv::DISOpticalFlowImpl::setPatchStride(int)' marked 'override', but does not override
     void setPatchStride(int val) CV_OVERRIDE { patch_stride = val; }
          ^~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:85:9: error: 'int cv::DISOpticalFlowImpl::getGradientDescentIterations() const' marked 'override', but does not override
     int getGradientDescentIterations() const CV_OVERRIDE { return grad_descent_iter; }
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:86:10: error: 'void cv::DISOpticalFlowImpl::setGradientDescentIterations(int)' marked 'override', but does not override
     void setGradientDescentIterations(int val) CV_OVERRIDE { grad_descent_iter = val; }
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:87:9: error: 'int cv::DISOpticalFlowImpl::getVariationalRefinementIterations() const' marked 'override', but does not override
     int getVariationalRefinementIterations() const CV_OVERRIDE { return variational_refinement_iter; }
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:88:10: error: 'void cv::DISOpticalFlowImpl::setVariationalRefinementIterations(int)' marked 'override', but does not override
     void setVariationalRefinementIterations(int val) CV_OVERRIDE { variational_refinement_iter = val; }
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\opencv\sources\modules\video\src\dis_flow.cpp:89 ...