how to list class methods in gdb?

Question

I've been googling for this and checking through the gdb manual but can't seem to find an answer to what I'm trying to do.

Is there a way to get gdb to print out a listing of all the methods for a given class type? The print command only seems to show the data members and fields, none of the methods are displayed for it.

Additionally, to take it a step further, is there a way to print all the correct virtual methods given a base *pointer? Say like for example:

struct A
{
  virtual void foo() {}
};

struct B : public A
{
  void foo() {}
};

int main()
{
  A *b = new B;
}

How can I get gdb to print variable *b and have it show the correct virtual method(s)?

Thanks

Answer 1

You can use ptype.

Suppose I add these lines to your example:

A alpha;
B beta;

Now in gdb I can ask for a description of a class type (or an instance of one):

(gdb) ptype alpha
type = class A {
  public:
    virtual void foo();
}

(gdb) ptype A
type = class A {
  public:
    virtual void foo();
}

(gdb) ptype beta
type = class B : public A {
  public:
    virtual void foo();
}

(gdb) ptype B
type = class B : public A {
  public:
    virtual void foo();
}

If I try that with a pointer, I get the declared type:

(gdb) ptype b
type = class A {
  public:
    virtual void foo();
} *

If I want the real type, I must set the `print object' variable:

(gdb) set print object on
(gdb) ptype b
type = /* real type = B * */
class A {
  public:
    virtual void foo();
} *

and then call ptype again to see what B has (I don't know how to do it in one step).