extern XBT_PRIVATE double sg_weight_S_parameter;
extern XBT_PRIVATE std::vector<std::string> surf_path;
extern XBT_PRIVATE std::unordered_map<std::string, simgrid::kernel::profile::Profile*> traces_set_list;
-extern XBT_PRIVATE std::set<std::string> watched_hosts;
+extern XBT_PRIVATE std::set<std::string, std::less<>> watched_hosts;
static inline void double_update(double* variable, double value, double precision)
{