message: Fix segmentation fault in cv::Mat::forEach
  This issue concerns only matrices with more dimensions than columns.
  See
diff: @@ -507,7 +507,7 @@ void Mat::forEach_impl(const Functor& operation) {
  this->rowCall2(row, COLS);
  }
  } else {
  - std::vector<int> idx(COLS); /// idx is modified in this->rowCall
  + std::vector<int> idx(DIMS); /// idx is modified in this->rowCall
  idx[DIMS - 2] = range.start - 1;
  for (int line_num = range.start; line_num < range.end; ++line_num) {
  