C:\Qt\5.8\mingw53_32\include\QtCore\qlist.h:493: предупреждение: deleting object of polymorphic class type 'Method' which has non-virtual destructor might cause undefined behaviour [-Wdelete-non-virtual-dtor] while(from != to) --to, delete reinterpret_cast<T*>(to->v); ^
C++ (Qt)class Method {public: ... virtual ~Method( void );};
C++ (Qt)class Method {virtual ~Method() = default;};