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copied!<ul> <li><p>Your classes don't have a virtual function. See <a href="http://www.parashift.com/c++-faq-lite/virtual-functions.html#faq-20.7" rel="nofollow noreferrer">FAQ 20.7</a></p></li> <li><p>Beacuse <code>Parent *&</code> is a reference to a pointer to a <code>Parent</code> object. You are passing a pointer to a <code>Child</code> -- these are incompatible types. You can bind a temporary to a const-reference i.e. if you change your parameter to:</p> <p><code>void RemoveObj(Parent* const& foo);</code></p></li> </ul> <p>But then you won't be able to do much with this.</p> <blockquote> <p>It was just a test code so I didn't make any virtual destructors. If I understand correctly in the second call of RemoveObj(), I get a temporary Parent* object which can be passed as a const reference to the function. Is this correct?</p> </blockquote> <p>I strongly suggest you run the following program in standard C++98 mode, once as in and then again after you have commented out <code>foo(b)</code> and uncommented <code>delete b</code>. Next, try putting in a <code>virtual</code> before <code>~s()</code>. The differences should be self-explanatory!</p> <pre><code>#include <iostream> using namespace std; struct s { s() {cout << __func__ << endl; } ~s() {cout << __func__ << endl; } }; struct t : s { t() {cout << __func__ << endl; } ~t() {cout << __func__ << endl; } }; void foo(s* const& x) { delete x; } int main() { t* b = new t; foo(b); //delete b; } </code></pre>

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