-XBT_PUBLIC(void) xbt_cfg_register_double (const char *name, double default_val, xbt_cfg_cb_t cb_set, const char *desc);
-XBT_PUBLIC(void) xbt_cfg_register_int (const char *name, int default_val, xbt_cfg_cb_t cb_set, const char *desc);
-XBT_PUBLIC(void) xbt_cfg_register_string (const char *name, const char*default_val,xbt_cfg_cb_t cb_set, const char *desc);
-XBT_PUBLIC(void) xbt_cfg_register_boolean(const char *name, const char*default_val,xbt_cfg_cb_t cb_set, const char *desc);
-XBT_PUBLIC(void) xbt_cfg_register_alias(const char *newname, const char *oldname);
-
-XBT_PUBLIC(void) xbt_cfg_aliases();
-XBT_PUBLIC(void) xbt_cfg_help();
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::declare_flag<double>") XBT_PUBLIC
+ void xbt_cfg_register_double(const char* name, double default_val, xbt_cfg_cb_t cb_set, const char* desc);
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::declare_flag<int>") XBT_PUBLIC
+ void xbt_cfg_register_int(const char* name, int default_val, xbt_cfg_cb_t cb_set, const char* desc);
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::declare_flag<std::string>") XBT_PUBLIC
+ void xbt_cfg_register_string(const char* name, const char* default_val, xbt_cfg_cb_t cb_set, const char* desc);
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::declare_flag<bool>") XBT_PUBLIC
+ void xbt_cfg_register_boolean(const char* name, const char* default_val, xbt_cfg_cb_t cb_set, const char* desc);
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::alias") XBT_PUBLIC
+ void xbt_cfg_register_alias(const char* newname, const char* oldname);
+
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::show_aliases") XBT_PUBLIC void xbt_cfg_aliases();
+XBT_ATTRIB_DEPRECATED_v323("Please use simgrid::config::help") XBT_PUBLIC void xbt_cfg_help();