There’s none. CLT is a smoke-free facility. This includes all restaurants, bars and airline clubs.
However, smoking is still allowed 100 feet away from the terminal's doorway. Because smoking areas are located outside the terminal, passengers are required to go through TSA security screening before going back to the gate area.
Get more info about the airport's other services at their Passenger Visitor FAQ's page.
If you need immediate information, call CLT at 704-359-4013. Other numbers are listed here.
For the latest updates and current CLT news, see the official online newsroom of Charlotte Douglas International Airport here.