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POWhy might my virtual function call be failing?
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  1. POWhy might my virtual function call be failing?
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    copied!<blockquote> <p><strong>Update:</strong> This issue is caused by bad memory usage, see <strong>solution</strong> at the bottom.</p> </blockquote> <p>Here's some semi-pseudo code:</p> <pre><code>class ClassA { public: virtual void VirtualFunction(); void SomeFunction(); } class ClassB : public ClassA { public: void VirtualFunction(); } void ClassA::VirtualFunction() { // Intentionally empty (code smell?). } void ClassA::SomeFunction() { VirtualFunction(); } void ClassB::VirtualFunction() { // I'd like this to be called from ClassA::SomeFunction() std::cout &lt;&lt; "Hello world!" &lt;&lt; endl; } </code></pre> <p><s>The C# equivalent is as follows:</s> Removed C# example, as it's not relevant to the actual problem.</p> <p>Why isn't the <code>ClassB::VirtualFunction</code> function being called when called from <code>ClassA::SomeFunction</code>? Instead <code>ClassA::VirtualFunction</code> is being called...</p> <p>When I <a href="https://stackoverflow.com/questions/738204/why-might-my-virtual-function-call-be-failing/738223#738223">force implementation of the virtual function</a> ClassA::VirtualFunction, like so:</p> <pre><code>class ClassA { public: virtual void VirtualFunction() = 0; void SomeFunction(); } class ClassB : public ClassA { public: void VirtualFunction(); } void ClassA::SomeFunction() { VirtualFunction(); } void ClassB::VirtualFunction() { // I'd like this to be called from ClassA::SomeFunction() std::cout &lt;&lt; "Hello world!" &lt;&lt; endl; } </code></pre> <p>The following error occurs at runtime, despite the derrived function deffinately being declared and defined.</p> <pre><code>pure virtual method called terminate called without an active exception </code></pre> <p><em>Note:</em> It seems like the error can be caused even by bad memory usage. See self-answer for details.</p> <h3>Update 1 - 4:</h3> <p><em>Comments removed (not releavnt).</em></p> <h3>Solution:</h3> <p><a href="https://stackoverflow.com/questions/738204/why-might-my-virtual-function-call-be-failing/738566#738566">Posted as an answer.</a></p>
 

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