Minimal GObject boilerplate (~ 8 lines of additional code)

foobar.c

#include "foobar.h"

G_DEFINE_TYPE (FooBar, foo_bar, G_TYPE_OBJECT)
static void foo_bar_class_init (FooBarClass *klass) {}
static void foo_bar_init (FooBar *self) {}

// Test program, doesn't count :)
int main()
{
    g_type_init();
    GObject *theObj = g_object_new(foo_bar_get_type(), NULL);
    g_object_ref(theObj);
    g_object_unref(theObj);
    g_object_unref(theObj);
    return 0;
}

foobar.h

#ifndef FOOBAR_H_
#define FOOBAR_H_ 1

#include <glib-object.h>

typedef struct FooBar_ {
  GObject parent;
}
FooBar;

typedef struct FooBarClass_ {
  GObjectClass parent_class;
}
FooBarClass;

GType foo_bar_get_type(void);

#endif /* FOOBAR_H_ */