I agree with the above.
I take my Lantus every night, around 9pm, and if (for whatever reason) my lantus dose is to high i wake up with a mild hypo of around 4mmol/L to have a snack..
If you are waking up with low sugars its because you are likely taking to much Lantus, or you should go to bed with higher sugars.. I try to get to bed when my sugars are around 6-6.5, so that i wake up they are around 5.5-6. Knowing that the lantus will slowly drop my sugars a bit ( less then 1 mmol/L) over the night.
On weekends or when i know I will be sleeping longer then 7-8 hours i eat before bed so that i can sleep in without having my sugars drop too much over the 12 hours i want to spend in bed lol So Friday and saturday night i go to be with my sugars around 7 lol so i can wake up at 1pm and still be around 5mmol/L lol