Timers don't start

[TPackard]

Our team has been having trouble with the WPILib Timer class, since the Get() method always returns 0.

void Fenrir::AutonomousInit() {
    timer.Start();
}

void Fenrir::AutonomousPeriodic() {
    std::printf("%f\n", timer.Get());
}

timer is an instance variable of Fenrir, which is our main robot class that inherits from IterativeRobot. When we run the above code, it constantly prints 0 and never changes. We've also tried using the HasPeriodPassed() and GetFPGATimestamp() methods, but they don't work either. What could the problem be?

Thanks in advance!