Identifiers must be unique to prevent confusion as to which variable or function is being referenced. Implementations can allow additional non-unique characters to be appended to the end of an identifier--making the identifieres identifiers appear unique while actually being indistinguishable.
To guarantee identifiers are unique, you must first determine the number of significant characters recognized by (the most restrictive) compiler you are using. This assumptions assumption must be documented in the code.
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In this example, both external identifiers consist of four universal characters but only the first three characters are unique. In practice, this means that both identifiers are referring to othe the same integer array.
Compliant Solution
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