Know who is the inheritor while debugging core dumps with GDB

Question

My process has crashed, and I have a core dump. I see that the process crashed while running a code similar to that :

class father
{
public:
  void virtual runVirtualFunc() = 0;
  void func()
  {
    runVirtualFunc();
    // ... crash here ...  THIS IS THE PLACE I NEED TO KNOW WHO IS THE INHERITOR (so I could analyze which "runVirtualFunc" ran).
  }
  virtual ~father() {}
};

class son1 : public father
{
public:
  void virtual runVirtualFunc() { /* do something 1*/} 
};

class son2 : public father
{
public:
  void virtual runVirtualFunc() { /* do something 2*/} 
};

I have a full call stack in the core dump, but I don't know who is the inheritor that runs the "func". Is there a way to figure it out (maybe by some pointer calculation tricks on this ? )

I don't have a live attached process, only core dump.

Answer 1

You can use info vtbl this or just print *this. You will see the inheritor in output (son1 in my example):

(gdb) info vtbl this 
vtable for 'father' @ 0x400920 (subobject @ 0x613c20):
[0]: 0x4007d8 <son1::runVirtualFunc()>
(gdb) p *this
$2 = {_vptr.father = 0x400920 <vtable for son1+16>}
(gdb)