/************************** Synchro simcalls **********************************/
SG_BEGIN_DECL()
XBT_PUBLIC smx_mutex_t simcall_mutex_init();
-XBT_PUBLIC smx_mutex_t SIMIX_mutex_ref(smx_mutex_t mutex);
-XBT_PUBLIC void SIMIX_mutex_unref(smx_mutex_t mutex);
XBT_PUBLIC void simcall_mutex_lock(smx_mutex_t mutex);
XBT_PUBLIC int simcall_mutex_trylock(smx_mutex_t mutex);
XBT_PUBLIC void simcall_mutex_unlock(smx_mutex_t mutex);