We consider the unconstrained minimization of a continuously different
iable function with semismooth gradient by line search methods; in par
ticular we focus on the problem of the acceptance of the unit stepsize
. We show that, under mild conditions, if the full search direction br
ings superlinear convergence, then the unit stepsize is eventually acc
epted so that: the Maratos effect does not occur. The relevance to thi
s issue of a generalization of the classical second-order sufficient c
ondition for optimality is pointed out.