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    <p>I will actually disagree with the "it depends". Never use option 2. If you want to use a translationtime constant, always use option 1 or std::array. The one advantage you listed, that dynamic arrays weigh nothing until allocated, is actually a horrible, huge disadvantage, and one that needs to be pointed out with great emphasis.</p> <p><strong>Do not ever have objects that have more than one phase of construction</strong>. Never, ever. That should be a rule committed to memory through some large tattoo. Just never do it.</p> <p>When you have zombies objects that are not quite alive yet, though not quite dead either, the complexity in managing their lifetime grows exponentially. You have to check in every method whether it is fully alive, or only pretending to be alive. Exception safety requires special cases in your destructor. Instead of one simple construction and automatic destruction, you've now added requirements that must be checked at N different places (# methods + dtor). And the compiler doesn't care if you check. And other engineers won't have this requirement broadcast, so they may adjust your code in unsafe ways, using variables without checking. And now all these methods have multiple behaviors depending on the state of the object, so every user of the object needs to know what to expect. <strong>Zombies will ruin your</strong> (coding) <strong>life.</strong></p> <p>Instead, if you have two different natural lifetimes in your program, use two different objects. But that means you have two different states in your program, so you should have a state machine, with one state having just one object and another state with both, separated by an asynchronous event. If there is no asynchronous event between the two points, if they all fit in one function scope, then the separation is artifical and you should be doing single phase construction.</p> <p>The only case where a translation time size should translate to a dynamic allocation is when the size is too large for the stack. This then gets to memory optimisation, and it should always be evaluated using memory and profiling tools to see what's best. Option 2 will never be best (it uses a naked pointer - so again we lose RAII and any automatic cleanup and management, adding invariants and making the code more complex and easily breakable by others). Vector (as suggested by bitmask) would be the appropriate first thought, though you may not like the heap allocation costs in time. Other options might be static space in your application's image. But again, these should only be considered once you've determined that you have a memory constraint and what to do from there should be determined by actual measurable needs.</p>
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    1. COYeah, your commment makes sense. When reading my code again, I realized that I was actually never having zombie objects since memory was allocated at construction though. So don't worry about that. Right, the only advantages were the gain from move operations in the end (already provided by std::vector if used). The only drawback of using a vector there would be some overhead compared to std::array. But I don't know if std::array has move semantics...
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    2. COOn the stack, you don't typically need moves, you need Return Value Optimisation, which although compiler-specific, is fairly universal. Other cases where moves might be used can almost always be done in-place (no copy), or when a copy is needed, it's actually needed (to put memory of one type into a different place), so moves don't work.
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