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Note the comment warning programmers that the macro is unsafe. The macro can also be renamed ABS_UNSAFE() to make it clear that the macro is unsafe. This compliant solution, like all the compliant solutions for this rule, has undefined behavior (see undefined behavior 36) if the argument to ABS() is equal to the minimum (most negative) value for the signed integer type. (See INT32-C. Ensure that operations on signed integers do not result in overflow for more information.)
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This compliant solution follows the guidance of PRE00-C. Prefer inline or static functions to function-like macros by defining an inline function iabs() to replace the ABS() macro. Unlike the ABS() macro, which operates on operands of any type, the iabs() function will truncate arguments of types wider than int whose value is not in range of the latter type.
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