Thread: passing vector<Base*> reference gives segmentation fault

Code:

int main() {
vector< Base*> scene_;

get_input(scene_);

for(size_t i =0; i < scene_.size(); i++)
{

std::cout << scene_[i]->getSomething();

}

return1;

}


void get_input( vector<Base*>&scene) {


Derived obj_a(some_param);

Derived obj_b(some_other_param);



scene.push_back(dynamic_cast<Base*> (&obj_a));

scene.push_back(dynamic_cast<Base*> (&obj_b));

}

I also have

Code:

class Derived : public Base {};

So I am trying to populate scene_ which is a vector of Base* objects which actually contains derived class objects;

I am encountering a segmentation fault in this code while I am iterating through the scene_

Code:

Derived obj_a(some_param);
Derived obj_b(some_other_param);
scene.push_back(dynamic_cast<Base*> (&obj_a));
scene.push_back(dynamic_cast<Base*> (&obj_b));

Your objects go out of scope when the function returns.

Try this.

Code:

Derived *obj_a = new Derived(some_param);
Derived *obj_b = new Derived(some_other_param);

scene.push_back(dynamic_cast<Base*> (obj_a));
scene.push_back(dynamic_cast<Base*> (obj_b));

By the way, you shouldn't use dynamic_cast here. The pointer to Derived would be implicitly converted to a pointer to Base.