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POWhy heap corruption when returning an object Mat?
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copied!<p>I don't understand why I get a corrupted heap error with this program (I'm using OpenCV for the class <code>Mat</code>): </p> <pre><code>class A { private: Mat image; static UINT ThreadProc( LPVOID pParam ) { A* pThis= (ClientNetwork*)pParam; UINT nRet= pThis->DoThreadProc(); // get out of 'static mode' return( nRet ); } UINT ClientNetwork::DoThreadProc() { vector<uchar> vect; while(1) { /**** initialize vect and get the image data to decode ****/ decode(vect); } } public: void decode(const vector<uchar>& vectorData){image=imdecode(vectorData, CV_LOAD_IMAGE_COLOR);} Mat get_image(){return image;} void start() {m_pcThread= AfxBeginThread(ThreadProc, this );} } int main() { A* a = new A(); a->start(); while(1) { Mat image = a->get_image(); } delete a; return 0; } </code></pre> <p>It seems that the error come from <code>Mat image = a->get_image();</code> because if I return a reference instead of a copy of the object, I don't have error anymore:</p> <pre><code>Mat* get_image(){return &image;} </code></pre> <p>and </p> <pre><code>Mat* image = a->get_image(); </code></pre> <p>I read that returning a copy of an object is more elegant in C++ than a reference. So I would like to know what is wrong.</p> <p>EDIT: Visual studio breaks at <code>a->decode(vect)</code> but it happens only when I return an object and not a reference.</p> <p>EDIT 2: I edited the code to reflect the full program. I think the problem comes from the shared object <code>a</code> which is copy and modified at the same time. I will see if the problem still occur using a mutex.</p>

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