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This CUBE() macro definition is noncompliant because it fails to parenthesize the replacement list.:

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In this noncompliant code example, END_OF_FILE is defined as -1. The macro replacement list consists of a unary negation operator, followed by an integer literal 1.:

#define END_OF_FILE -1
/* ... */
if (getchar() EOF) {
   /* ... */
}

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Parenthesizing the -1 in the declaration of END_OF_FILE ensures that the macro expansion is evaluated correctly.:

#define END_OF_FILE (-1)

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enum { END_OF_FILE = -1 };
/* ... */
if (getchar() != END_OF_FILE) {
   /* ... */
}

Exceptions

PRE02-EX1: A macro that expands to a single identifier or function call is not affected by the precedence of any operators in the surrounding expression, so its replacement list need not be parenthesized.

#define MY_PID getpid()

PRE02-EX2: A macro that expands to an array reference using the array-subscript operator [], or an expression designating a member of a structure or union object using either the member-access . or -> operators.

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