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Dynamic_cast not working

I have a base class and a derived class. Each class has a .h file and a .cpp file.

I am doing a dynamic_cast of a base class object to a derived class in the following code:

h files:

class Base
{
  public:
    Base();
    virtual ~Base();
};

class Derived : public Base
{
  public:
    Derived(){};
    void foo();
};

class Another
{
  public:
    Another(){};
    void bar(Base* pointerToBaseObject);
};

cpp files:

Base::Base()
{
    //do something....
}
Base::~Base()
{
    //do something....
}
void Derived::foo()
{
    Another a;
    a.bar(this);
}
void Another::bar(Base* pointerToBaseObject)
{
    dynamic_cast<Derived*>(pointerToBaseObject)
}

For some strange reason, casting fails (returns NULL). However, casting succeeds if I move the Derived class constructor implementation from .h to the .cpp file.

What can cause this?

The compiler is gcc 3.1, on Linux-SUSE. BTW, I see this behavior only on this platform, and the same code works fine in Visual Studio.

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6 answers

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