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copied!<p>Try/catch function blocks are frowned upon, in the same way as goto --there might be some corner case where they make sense, but they are better avoided: when an object fails to be constructed, best thing you can do is fail and fail fast.</p> <p>On you specific questions, when an exception is thrown in a constructor, all fully constructed subobjects will be destroyed. That means that in the case of <code>b</code> it will be destroyed, in the case of <code>c</code>, it being a raw pointer, nothing is done. The simplest solution is changing <code>c</code> to be a smart pointer that handles the allocated memory. That way, if <code>d</code> throws, the smart pointer will be destroyed and the object released. This is not related to the try/catch block, but rather to how constructors work.</p> <p>It is also, in general, unsafe to delete the pointer from the catch block, as there is no guarantee of the actual value of the pointer <em>before</em> the initialization is performed. That is, if <code>b</code> or <code>c</code> throw, it might be the case that <code>c</code> is not 0, but is not a valid pointer either, and deleting it would be undefined behavior. As always there are cases, as if you have a guarantee that neither <code>b</code> nor <code>c</code> will throw, and assuming that a <code>bad_alloc</code> is not something you usually recover from, then it might be safe.</p> <p>Note that if you need to keep a pointer with a raw pointer for some specific reason, it is better to initialize it to 0 in the initialization list, and then create the object inside the construction block to avoid this problem. Remember also that holding more than one (raw) resource directly in a class makes it really hard to ensure that no resource is leaked -- if first resource is created and assigned, and the second one fails, the destructor will not be called and the resource will leak. Again, if you can use a smart pointer you will have one less problem to deal with.</p>

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