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    <p>I noticed in your comments that you have an object allocated on the stack that you want a <code>std::shared_ptr</code> to ... if that is the case, you'll have to copy your object from the stack into the heap doing something like:</p> <pre><code>std::shared_ptr&lt;my_object_t&gt; sh_ptr(new my_object_t(stack_object)); </code></pre> <p>That will then allocate a copy of your stack-object on the heap and created a <code>std::shared_ptr</code> from that heap-allocated object. You can then copy your newly created shared pointer into a container, etc.</p> <p>Also I would concur with Nemo's comments that you should have your class <code>CurveShift</code> hold a copy of the <code>shared_ptr</code> rather than a constant reference to a <code>Curve</code> class object ... that way the <code>shared_ptr</code> object will control the life-time of the pointer reference, and should a container or some other object try to destroy the memory pointed to by the <code>shared_ptr</code> instance during it's own deconstruction, the memory reference will still be maintained in the <code>CurveShift</code> instance since calling the destructor of the <code>shared_ptr</code> elsewhere will not actually deallocate the memory for the object on the heap as your <code>CurveShift</code> instance object has an active reference to that heap allocated object held by the <code>shared_ptr</code>. By holding just a constant reference, you remove the whole advantage of using a <code>shared_ptr</code> type which is controlled deconstruction of an object allocated on the heap through some form of reference-counting. </p> <p>In the end, I would write you class like:</p> <pre><code>class CurveShift: public Curve { public: CurveShift(const shared_ptr&lt;Curve&gt;&amp; ptr): _curve(ptr) { // ... rest of constructor } private: shared_ptr&lt;Curve&gt; curve_; //will remain valid for lifetime of CurveShift instance // ... }; </code></pre> <p>And then you would make a call like:</p> <pre><code>CurveShift cs(SomeGlobalRepository::Get("key")); </code></pre> <p>Which copies in the <code>shared_ptr</code> to your <code>CurveShift</code> instance and increases the reference count to the pointer on the heap its managing.</p>
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    1. POReferences to boost::smart_ptr pointed to object and checking their validity
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    1. CO+1 -- for your first code snippet though I would recommend `std::make_shared` instead. One should not create unnamed `shared_ptr` that way because it can lead to memory leaks if an exception is thrown and the compiler is unfavorable to you in how it orders the calls.
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    2. COSee Scott Meyers' Effective C++ Item #17: Store newed objects in smart pointers in standalone statements.
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    3. CO@Billy ONeal: Thanks for the tip ... I've updated the code.
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