GObject: NULL virtual methods during instance init

[Gustavo J A M Carneiro <ee96090 fe up pt>]

  I'm getting something weird. I have class A and class B, where class B
is derived from class A. Class A defines a virtual method, "vfunc",
which is pure virtual and only implemented in class B.
I created an instance of class B. During class A's instance init func
(but called with a B object) I try to invoke vfunc this way:

 AClass *class;
 class = A_GET_CLASS(self);
 if (class->vfunc)
    class->vfunc(self, args);

But at this point class->vfunc is NULL. I do initialize it correctly at
class B's class_init function.
  Generally, I've been using GObject with virtual methods for some time
and had no problem at all until now.
  Am I doing anything wrong here? What?
  Thanks in advance for any help.

--
Gustavo Joćo Alves Marques Carneiro <ee96090 fe up pt>
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