Warning C4099: type name first seen using 'class' now seen using 'struct' (MS VS 2k8)

Question

Is this warning anything to worry about? I\'ve read that it can cause erratic behaviour?

It\'s an example I\'m trying to compile, could someone explain to me why the

Answer 1

In c++ the only difference between a class and a struct is that class's member variables, member functions and base classes are private by default, while in a struct they're by default public; so, the fact that the class is POD should not make any difference here.
I would guess that this warning comes from code maintenance (definition updated somewhere but not somewhere else), and fix the code so that the warning disappears (e.g. using class in the typedef).