In this day and age, could it not fly 2 reds/2 whites perfectly whilst in LNAV/VNAV? After all its a GPS derived signal.
VNAV profile uses barometric altimeter, which has its usual failings when outside temperature does not conform to ISA. GPS for vertical profile is only used for SBAS (LPV), which is not yet available on the 737 to the best of my knowledge.
ICAO does not prescribe any procedures for correcting the altitudes for temperatures warmer than ISA, and one is not to fly below the prescribed altitudes by the State, hence you will be high on profile in hot weather and will have to deal with it once you are visual, as in any other aircraft.