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POClosed source library - endianness - negative -1 is read as 0 when deserializing
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copied!<p>I am reading some floats from a binary xml and deserealize them into a struct containing 4 floats (32 bit floats to be exact). All the values get read correctly, except for those that are -1. </p> <p><em>Is this an endian-related issue?</em></p> <p>What should I look for if <code>-1</code> is converted to <code>0</code> and <em>every</em> other value is correctly deserialized? (I mean, is there an obvious, common mistake or source for a mistake I should take into account?). I do not have any access to the library that does this and I can't provide you with any details since it's confidential.</p> <p>Before this question really gets closed, I'd like to post a small hint (no code due to a harsh NDA condition):</p> <ul> <li>the library I'm working with converts some binary data from an xml to its specific types</li> <li><p>it does this in a very ugly way: </p> <p>value = <em>(T</em>)srcBuffer; </p> <p>SwapByte(value);</p></li> <li><p><code>-1</code> is thus directly read and assumed to be in BigEndian format. Unfortunately, <code>-1</code> amounts to <code>somethingE-47</code> which is indeed a very small number in BigEndian format. The assembly instructions perform some quantization <em>and</em> round it to zero. The ulterior <code>SwapByte</code> instruction will thus get the wrong data and fail for this odd case. It is an architectural problem related to an IBM/PowerPC processor. </p></li> </ul> <p>Would a <code>memcpy</code> work better and avoid the ugly quantization artifact? I can't do the swapbyte before the conversion as I will surely deteriorate other parts.</p>

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