A good friend and 2A supporter sent this to me:

 I spoke to Assemblyman David DiPietro about the big problem gun owners will have when marijuana becomes legal to buy and to use.  This is a way the federal government can take away your second amendment rights.  It seems that the legal purchase of pot will need you to show proof of your age with a government document with a photo.  Usually this is a driver's license.  That information can be captured by the government and your name will be on a list of marijuana purchases which can be sent to the FBI and the NICS list to make you ineligible for purchasing guns.  It also opens the door for the feds to check the list against the list of people who own guns, like pistol permits an hunting licenses and could give them a reason to knock on your door, arrest you and confiscate all your guns.  This last sentence is my opinion, but I believe this federal government is capable and willing to do so as their passion for "more gun control" increases.  Attached is the statement from Assemblyman DiPietro who has a perfect Second Amendment record as a legislator.  I believe what he says. Pass this on to your gun owning friends.

From Assemblyman DiPietro:

Hi .."To all firearms owners: please be advised that any purchase of legalized marijuana in New York State will result in the confiscation of your firearms. Marijuana is still a controlled substance according to federal law. Federal law supercedes state law.