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    <p>I am not familiar with coverity or the exact rules that it uses, but it seems that you will have a memory leak if the name of the node is already in the map. That is, if the body of your if statement is not executed, then you loose the pointer to the memory that you just allocated. Perhaps you wanted something like:</p> <pre><code>if (m_name2NodeMap.find(nodeName) == m_name2NodeMap.end()) m_name2NodeMap[nodeName] = NodePtr; else delete NodePtr; NodePtr = NULL; </code></pre> <p>Edit: since I responded almost at the same time as Daemin, let me add more details:</p> <p>As ildjarn mentioned, you also need to deallocate those objects that do end up in the map by adding a destructor:</p> <pre><code>~graph() { for( std::map&lt; std::string, node*&gt;::iterator i = m_name2NodeMap.begin(); i != m_name2NodeMap.end(); ++i ) { delete i-&gt;second; } } </code></pre> <p>For completeness, I should note that:</p> <ol> <li>The map will be deleted automatically after the destructor finishes because it's a member variable.</li> <li>The entries in the node map will be deleted automatically when the map is deleted.</li> <li>The string keys will be deleted when the entries are deleted.</li> </ol> <hr> <p>The preferred way to deal with complex object lifetimes is to use a smart pointer. For example, the <a href="http://www.boost.org/doc/libs/1_46_1/libs/smart_ptr/shared_ptr.htm" rel="nofollow">boost::shared_ptr</a> or the tr1::shared_ptr would work like this. Note: I may not have the syntax exact.</p> <pre><code>class node { ... } class graph { public : void populateGraph() { std::string nodeName = getNodeName(); boost::shared_ptr&lt; node &gt; NodePtr( new node(nodeName) ); NodePtr-&gt;setLevel(-1); if (m_name2NodeMap.find(nodeName) == m_name2NodeMap.end()) m_name2NodeMap[nodeName] = NodePtr; } .... private : std::map&lt; std::string, boost::shared_ptr&lt;node&gt; &gt; m_name2NodeMap; } }; </code></pre> <p>See how we've eliminated the destructor and explicit calls to delete? Now the node objects will be destroyed automatically just like the node names.</p> <p>On another node, you should look into the <a href="http://www.cplusplus.com/reference/stl/map/insert/" rel="nofollow">std::map::insert</a> function which should eliminate that if statement all together.</p>
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    1. COThanks for the answer. I have a question about "2. The entries in the node map will be deleted automatically when the map is deleted". By entry do you mean each element is deleted..If so, why is the node* in each element not deleted. E.g. Map["A"] = AddrofObjA. Let's say each node Obj takes 50 bytes, wouldn't deletion of entry "A" in map, delete the 50 bytes starting from AddrofObjA? Thanks
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    2. COshared pointers are for expert only. Shared ownership is extremely difficult to manage properly (both semantically and technically) and should only be envisaged as a last resort. Oh, and if one needs a destructor, one also needs a copy constructor and assignment operator.
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    3. CO@srikrish: what you are storing in the map are pointers to nodes. The map is only storing the key "A" and a memory address. When you delete the element from the map, it frees the memory associated with the key and the address. However, it does not automatically delete whatever is stored at the address. Note: I am glossing over the issue that the key is stored in an std::string object which does some funny stuff with memory management, but it gives the illusion that the key is just stored right there in the element and deleted with it.
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