if (not check_for_cycle(dag)) {
std::string base = simgrid::xbt::Path(filename).get_base_name();
XBT_ERROR("The DOT described in %s is not a DAG. It contains a cycle.", base.c_str());
if (not check_for_cycle(dag)) {
std::string base = simgrid::xbt::Path(filename).get_base_name();
XBT_ERROR("The DOT described in %s is not a DAG. It contains a cycle.", base.c_str());