if(this->attr_get<T>(keyval, &value, &flag)==MPI_SUCCESS){
int ret = call_deleter<T>((T*)this, elem, keyval,value,&flag);
if(ret!=MPI_SUCCESS)
return ret;
}
if(this->attr_get<T>(keyval, &value, &flag)==MPI_SUCCESS){
int ret = call_deleter<T>((T*)this, elem, keyval,value,&flag);
if(ret!=MPI_SUCCESS)
return ret;
}