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Only pass a nonstandard-layout type object across execution boundaries when both sides of the execution boundary adhere to the same ABI—for instance, ABI. This is permissible if the same version of the a compiler is used to compile both sides of the execution boundary, or if the compiler used to compile both sides of the execution boundary is ABI-compatible across multiple versions, or if the differing compilers used document that they adhere to the same ABI.
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