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Note that it is a common mistake to choose a reserved name for the name of the macro used in the inclusion guard. See DCL37-C. Do not declare or define a reserved identifier.

Risk Assessment

Failure to include header files in an inclusion guard can result in unexpected behavior.

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ISO/IEC 9899:2011 Section 5.1.1, "Translation environment," section 6.10, "Preprocessing directives," and section 7.1.2, "Standard headers"

MISRA Rule 19.5

Bibliography

[Plum 1985] Rule 1-14

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