Apparent Segfault in std::vector Iterator

[tatman]

I've got a class with a simple function for returning an entry found in a vector.


Something like this:

class A
{
  public:
    B* getB()
    {
      return bees[index];
    }

  private:
    unsigned index;
    vector< B* > bees;
};

When I run this function, I get a segfault. (gdb traces the segfault to this function) "Okay," I say to myself. "Must just be because index is out of bounds somehow."

Wrong answer. Adding a check that index is less than bees.size() gives me a segfault in the size function, on the begin iterator.

The function is not trying to return a null pointer or some such thing, all 'B*'s pass a functionality test with flying colors before being pushed into the vector.

Any ideas from this bright crowd?

[Disch]

Are you doing something silly like raw memory operations on your A object?

1) Make sure A's ctor is called (don't use malloc() -- use new)
2) Make sure you're not memset'ing or memcpy'ing any A objects

[tatman]

Nuh uh, the code that handles these objects looks something like this:

B* b = new B();

// Various methods of b are run, all working without any problems.

A* a = new A();

a->addB( b ); // 'addB' is just 'bees.push_back( b );'

B* tempB = a->getB(); // (with index = 0) Segfault.

tempB->doMethod(); // Doesn't happen. 

Oh wait...

Okay, that's embarrassing. I just recently added a pointer as a member of the B class, and forgot to implement a copy constructor... Good job wasting three hours, self.

Thanks anyway!