g++'s cool messages (1)

In file included from ../cache/CostFunction.hpp:3,
                from Session.hpp:56,
                from Session.cpp:44:
../metadata/UserPreferences.hpp: In copy constructor `Feature::Feature(const Feature&)':
../metadata/UserPreferences.hpp:193: warning: cannot pass objects of non-POD
  type `const struct Feature' through `...'; call will abort at runtime
../metadata/UserPreferences