Some environments provide environment pointers that are valid when main() is called but may be invalided by operations that modify the environment.
SubclauseJSubclause J.5.1 of the C Standard [ISO/IEC 9899:2011] states:
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For example, when compiled with GCC 3GCC 4.48.6 1 and run on a 32-bit Intel GNU/Linux machine, the following code,
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