Method fail

gecode/kernel/gpi.hpp:125–133

    : b(&fst), invd(1.0), npid(0U), us(false) {}

  forceinline void
  GPI::fail(Info& c) {
    m.acquire();
    c.afc = invd * (c.afc + 1.0);
    if (c.afc > Kernel::Config::rescale_limit)
      for (Block* i = b; i != nullptr; i = i->next)
        i->rescale();
    m.release();
  }

  forceinline double
  GPI::decay(void) const {