Can't really stockpile gas. Even after treatment with Sta-Bil, it gets gummy and useless after a year or so.
I've put gas in one of my cars more than a year ago, as it's a project (1989 BMW 320i coupe) waiting for spare cash to burn, I've started it the other day (using cables) and it ran fine, so the gas must still be OK.
Don't properly care for your tools, they'll eventually let you down. Sometimes, when your life depends upon their proper functioning.