message: a sanity check
diff: @@ -483,6 +483,11 @@ void drawStackedBar(const std::string & label, std::vector<StackedBarItem> & h,
  {
  real_width += scale(i.fraction);
  }
  + if (real_width > 2*width)
  + {
  + std::cout << "ERROR: sum of fractions > 2 ("<< real_width << " > " << width << ")" << std::endl;
  + return;
  + }
  drawBar((int)label.length(), DOWN_AND_RIGHT, real_width, DOWN_AND_LEFT);
  std::cout << label << VERTICAL;
  for (const auto & i : h)
  