  We express the two-massless-flavor Gell-Mann--Oakes--Renner ratio in terms of
low-energy pi-pi observables, including the O(p^6) double chiral logarithms of
generalized chiral perturbation theory. Their contribution is sizeable and
tends to compensate the one from the single chiral logarithms. However it is
not large enough to spoil the convergence of the chiral expansion. As a signal
of reduced theoretical uncertainty, we find that the scale dependence from the
one-loop single logarithms is almost completely canceled by the one from the
two-loop double logarithms.
