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In this noncompliant code example, the complete object representation is accessed when comparing two objects of type S. Per the C++ Standard, [class], paragraph 13 [ISO/IEC 14882-2014], classes may be padded with data to ensure that they are properly aligned in memory. The contents of the padding and the amount of padding added is implementation-defined. This can lead to incorrect results when comparing the object representation of classes instead of the value representation, as the padding may assume different unspecified values for each object instance.
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