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A particular platform (that is, hardware, operating system, compiler, and Standard C library) might guarantee that a memory address is correctly aligned for the pointer type, and actually contains a value for that type. A common practice is to use addresses that are known to point to hardware that provides valid values.
Exceptions
INT36-C-EX1: A null pointer can be converted to an integer; it takes on the value 0. Likewise, the The integer value 0 can be converted to a pointer; it becomes the null pointer.
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