XBT_PRIVATE bool TRACE_vm_is_enabled();
XBT_PRIVATE bool TRACE_disable_link();
XBT_PRIVATE bool TRACE_disable_speed();
-XBT_PRIVATE bool TRACE_disable_destroy();
XBT_PRIVATE bool TRACE_basic();
XBT_PRIVATE bool TRACE_display_sizes();
XBT_PRIVATE int TRACE_precision();