While it has been common practice to use integers and pointers interchangeably in C, the C99 standard states that pointer to integer and integer to pointer conversions are implementation-defined.
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According to C99 \[[ISO/IEC 9899-1999|AA. C References#ISO/IEC 9899-1999]\], the only value that can be considered interchangeable between pointers and integers is the constant 0. Except in this case, conversions between integers and pointers may have undesired consequences depending on the implementation: |
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