while (action != nullptr) {
SD_task_t task = static_cast<SD_task_t>(action->get_data());
XBT_VERB("Task '%s' failed", SD_task_get_name(task));
SD_task_set_state(task, SD_FAILED);
sd_global->return_set->insert(task);
while (action != nullptr) {
SD_task_t task = static_cast<SD_task_t>(action->get_data());
XBT_VERB("Task '%s' failed", SD_task_get_name(task));
SD_task_set_state(task, SD_FAILED);
sd_global->return_set->insert(task);