linesearch fails

[electrodan99]

When the initial x in the Rosenbrock example is changed from zeros to random, the linesearch fails.
VectorXf x = VectorXf::Random(n);

The linesearch fails the sufficient decrease condition.

I ran into this trying to use this BFGS optimizer on a neural net. Reproduced it with the included Rosenbrock example. I haven't figured out the problem, but was wondering if you know.