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POstd::tuple memory alignment
 

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    <p>Is there any formal specification for the layout and memory alignment for the pseudo members of a tuple?</p> <p>Is there anyway to modify the memory alignment of types in a tuple? Is it effected by a #pragma pack() directive?</p> <p>For example:</p> <pre><code>typedef std::tuple&lt;uint8_t, uint32_t&gt; myTuple; </code></pre> <p>Is there any specification that says this will be in memory the same as:</p> <pre><code>#pragma pack() // Default packing struct myStruct { uint8_t first; uint32_t second; } </code></pre> <p>Apologies if this is a stupid question but I don't entirely understand alignment when it comes to templates.</p> <p><strong>Edit: Example of what I'm trying to accomplish</strong></p> <p>Currently I have something along the lines of...</p> <pre><code>#pragma pack(push) #pragma pack(4) struct cTriangle { uint32 Index[3]; }; #pragma pack(pop) template &lt;class T&gt; inline bool Read(cFileStream&amp; fStream, std::vector&lt;T&gt;&amp; vec) { if (!vec.size()) return true; // fStream.Read(void* pBuffer, size_t Size) // Just a wrapper around a binary ifstream really return fStream.Read(&amp;vec[0], sizeof(T) * vec.size()); } std::vector&lt;cVector3&gt; vPoint; vPoint.resize(Verticies); bool result = Read(FileStream, vPoint); </code></pre> <p>If I wanted to typedef <code>cTriangle</code> as <code>std::tuple&lt;uint32, uint32, uint32&gt;</code> for metaprogramming purposes would I still be able to read/write to the raw memory of the tuple (and thus a vector of tuples) or would that memory have unknown alignment?</p>
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    1. COAsking out of curiosity, or is there a problem we can help you solve?
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    2. CO@GManNickG, I'm actually looking to see if I can use tuple as a replacement for structs and then place them in a vector which I can read and write all at once instead of element by element, tuple argument by tuple argument. I will update the main post to include an example.
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