An object that has volatile-qualified type may be modified in ways unknown to the implementation or have other unknown side effects. It is possible to reference a volatile object by using a non-volatile value, but the resulting behavior is undefined. According to ISO/IEC 9899:1999, Section 6.7.3 "Type Qualifiers":
If an attempt is made to refer to an object defined with a volatile-qualified type through use of an lvalue with non-volatile-qualified type, the behavior is undefined
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Noncompliant Code Example
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