Modifying a variable through a pointer of an incompatible type (other than unsigned char) can lead to unpredictable results. This is often caused by a violation of aliasing rules. C, Section 6.5, para. 7 [ISO/IEC 9899:2011], specifies those circumstances in which an object may or may not be aliased.
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Accessing an object by means of any other lvalue expression (other than unsigned char) results in undefined behavior . See undefined behavior 34 of Annex J.
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