Get out of there fast. Also note that very probably the company isn't sending the money it's supposed to be withholding from your paychecks to the government, so you will have tax problems this year, that are the company's fault but you will end up having to resolve.
I.E., your paystubs say the company withheld $5,000 from your paychecks and gave you $10,000. You file your tax return, and the IRS comes back and says, "We don't know what you're talking about, Company X didn't send us any $5,000. You can go ahead and send us the $5K now though."
Missing payroll is a VERY VERY VERY VERY bad sign. Do not continue to waste your time working there for free.
I.E., your paystubs say the company withheld $5,000 from your paychecks and gave you $10,000. You file your tax return, and the IRS comes back and says, "We don't know what you're talking about, Company X didn't send us any $5,000. You can go ahead and send us the $5K now though."
Missing payroll is a VERY VERY VERY VERY bad sign. Do not continue to waste your time working there for free.