Thread: __declspec(align(16)) and function parameters

  1. #1
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    __declspec(align(16)) and function parameters

    Hello,
    I am using align(16) to align a structure. I use
    typedef __declspec(align(16)) Vector3 Vec3;

    Now, I am passing that Vec3 to a function, but the compiler (MSVC++ 7) says that Translate': formal parameter with __declspec(align('16')) won't be aligned

    Can't align(16) structures be used as parameters?
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  2. #2
    and the hat of int overfl Salem's Avatar
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    Why would you want to pass a (large?) structure by value anyway?

    Why not pass a pointer (or a reference) to the structure, then it will maintain its alignment since it's not actually copied anywhere.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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  3. #3
    Registered User Codeplug's Avatar
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    That use of align() will only align the Vec3 instance of Vector3.

    Read more about it here.

    gg

  4. #4
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    So what should I do to pass a structure which has the align(16) in front of it?
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