working of backtrace command in GDB

[Varun Kumar Erigila]

Hello Everyone,
              I'm trying to figure out whether gdb makes use of CFI information for "backtrace command."
              In case of watchpoints, gdb tries to figure out whether the frame containing the variable on which watchpoint is set is still present by going through all the frames in stack. (it calls execute_cfa_program function to figure this out).
              But in the case of the backtrace command it does not call the execute_cfa_program to unwind all the frames.
              Is there another mechanism gdb uses to unwind the stack frames apart from CFI information.

Regards,
Varun