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+---- Thread: Rule 2.5 vs. include guards (/showthread.php?tid=1317)
Rule 2.5 vs. include guards - sg2 - 27-02-2017
Hi.
It is not completely clear what is meant by use of a macro in Rule 2.5. There is definition of a use of an expression in the Glossary, but not of a macro.
If taken literally, rule 2.5 means that standard include guards are forbidden:
#ifndef HEADER_H
#define HEADER_H // Not used unless another #ifndef is encountered somewhere inside
...
#endif
Re: Rule 2.5 vs. include guards - misra-c - 30-03-2017
Your example is compliant with rule 2.5. The #ifndef HEADER_H is considered to be a use of the macro name, even though it appears before the #define.