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Date: Wed, 12 Jul 2006 20:29:00 -0000
From: "michid@gmail.com" <michid@gmail.com>
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To:  gcc-help@gcc.gnu.org
Subject: Wrong virtual method called (bug?)
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The following program gives different output on g++ 3.3.6 and 4.0.3. 
With 3.3.6 it prints

D::foo()
D::foo()

with 4.0.3 it prints

C::foo()
D::foo()

which is what I'd expected it to print. Is this a known issue?

Michael


#include <iostream>
using namespace std;

struct B {
   virtual void foo() const = 0;
};

struct C: B {
   virtual void foo() const {  cout << "C::foo()" << endl;  }
};

struct D: B {
   virtual void foo() const {  cout << "D::foo()" << endl;  }
};

struct A {
   const B &b;
   A(const B& x = C()): b(x) {}
   void foo() {  b.foo();  }
};

int main() {
   A a1 = A(C());
   A a2 = A(D());
   a1.foo();
   a2.foo();
   return 0;
}