Merge pull request #7854 from alalek:backports_2016

(2.4) Backports from master branch (#7854)

modules/stitching/CMakeLists.txt

@@ -1,4 +1,5 @@
 set(the_description "Images stitching")
+ocv_warnings_disable(CMAKE_CXX_FLAGS -Woverloaded-virtual)
 if(ENABLE_DYNAMIC_CUDA)
   add_definitions(-DDYNAMIC_CUDA_SUPPORT)
   ocv_define_module(stitching opencv_imgproc opencv_features2d opencv_calib3d opencv_objdetect OPTIONAL opencv_nonfree)

modules/stitching/include/opencv2/stitching/stitcher.hpp

@@ -43,6 +43,11 @@
 #ifndef __OPENCV_STITCHING_STITCHER_HPP__
 #define __OPENCV_STITCHING_STITCHER_HPP__
 
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Woverloaded-virtual"
+#endif
+
 #include "opencv2/core/core.hpp"
 #include "opencv2/features2d/features2d.hpp"
 #include "opencv2/stitching/warpers.hpp"
@@ -171,4 +176,8 @@ private:
 
 } // namespace cv
 
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
 #endif // __OPENCV_STITCHING_STITCHER_HPP__