  Integrated positioning and communication (IPAC) system and reconfigurable
intelligent surface (RIS) are both considered to be key technologies for future
wireless networks. Therefore, in this paper, we propose a RIS-enabled IPAC
scheme with the millimeter wave system. First, we derive the explicit
expressions of the time-of-arrival (ToA)-based Cram\'er-Rao bound (CRB) and
positioning error bound (PEB) for the RIS-aided system as the positioning
metrics. Then, we formulate the IPAC system by jointly optimizing active
beamforming in the base station (BS) and passive beamforming in the RIS to
minimize the transmit power, while satisfying the communication data rate and
PEB constraints. Finally, we propose an efficient two-stage algorithm to solve
the optimization problem based on a series of methods such as the exhaustive
search and semidefinite relaxation (SDR). Simulation results show that by
changing various critical system parameters, the proposed RIS-enabled IPAC
system can cater to both reliable data rates and high-precision positioning in
different transmission environments.
