undefined reference to vtable

[Jonathan Wakely]

On 16 July 2011 19:20, Kalle Olavi Niemitalo wrote:
> eric <cneric12lin0@gmail.com> writes:
>
>> actually that book even did not specially define Superhero::walk(),
>> that is I add by myself to escape my compile's error
>> (is that right? or book's is right?)
>
> I see you did not define Superhero::eat(), however.  You must
> define all the virtual functions of class Superhero, even if the
> program never calls them.  http://gcc.gnu.org/faq.html#vtables

http://gcc.gnu.org/ml/gcc-help/2011-07/msg00143.html