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    <p>These are not doing the same thing:</p> <pre><code>ClassA::ClassA(void) : objectB(ClassB( this )), objectC(ClassC( std::make_shared&lt;ClassA&gt;(*this) )) </code></pre> <p>The first initializer creates a temporary of type <code>ClassB</code> with the <code>this</code> pointer and initializes <code>objectB</code> by copying that temporary:</p> <pre><code>objectB(ClassB( this )) </code></pre> <p>The second creates a <em>new</em> <code>ClassA</code> as a copy of <code>*this</code>, stores it in a <code>shared_ptr</code>, then initializes a temporary <code>ClassC</code> with that <code>shared_ptr</code>, then initializes <code>objectC</code> by copying that temporary:</p> <pre><code>objectC(ClassC( std::make_shared&lt;ClassA&gt;(*this) )) </code></pre> <p>Your syntax is unnecessarily verbose, avoid the temporaries and copies and initialize your members directly:</p> <pre><code> objectB( this ), objectC( std::make_shared&lt;ClassA&gt;(*this) ) </code></pre> <p>This is equivalent to:</p> <pre><code> objectB( this ), objectC( std::shared_ptr&lt;ClassA&gt;( new ClassA(*this) ) ) </code></pre> <p>It should be clear that <code>objectB</code> has a pointer to <code>this</code> but <code>objectB</code> has a (shared) pointer to a <em>different</em> object, that is a copy of <code>*this</code>.</p> <p>The point of a <code>shared_ptr</code> is it owns the pointer you give it, and will (generally) delete the pointer. You can't have a <code>shared_ptr</code> that owns <code>this</code> in an object's constructor, because until the object has finished being constructed it can't be owned by any <code>shared_ptr</code> (the pointer you give to a <code>shared_ptr</code> is a pointer to a <em>complete</em> object, not a partially constructed one half way through it's constructor) so there's no safe way to get a <code>shared_ptr</code> referring to <code>this</code> that you can pass to <code>objectC</code>'s constructor. There is a way to do it, using the aliasing feature of <code>shared_ptr</code> but I think you should re-examine your design and ask <em>why</em> you want <code>objectC</code> to "own" the object it's part of ... that doesn't make sense.</p>
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    1. POWhat is the correct syntax to construct a class with a shared_ptr as member field?
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    1. USJonathan Wakely
    1. USJonathan Wakely
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    1. COThat makes a lot of sense, thanks! I indeed don't want that objectC "owns" objectA, it is the other way around. I do want however that objectC knows its "owner", and therefore it needs some reference to objectA. Is it best practice then to use a general pointer for it?
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      1. USphysicalattraction
    2. CO@physicalattraction, yes, a simple pointer is fine if you don't need to own the thing it points to, and you know the pointer will always remain valid. In your case the parent object will always outlive its sub-objects, so it's safe for the sub-objects to store a `ClassA*` to their parent.
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