It depends on the cop and the city I guess. Most departments run a persons check before making a report to see if they are dealing with someone who is wanted or has a criminal history. If they run the ID the warrant will come up and he will be arrested.
Don't know how it is in NC but the only time I ever filed one (in Nevada) I filed it with a desk employee, not an actual cop, and my ID wasn't run through a computer or anything.
If it is a bench warrant for not showing up for court or something then you may as well just get it cleared up now because ID theft is horrible and they will keep using your information to bury you in debt until your credit is all burned up if you don´t know who is doing it. Do you know who the person is?
I wouldn´t chance it as they are going to ask you for contact information and stuff and if they do run you through the computer your screwed.