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MISRA C:2023 Rule 21.2

A reserved identifier or reserved macro name shall not be declared

Since R2024a

Description

Rule Definition

A reserved identifier or reserved macro name shall not be declared.

Rationale

The Standard allows implementations to treat reserved identifiers specially. If you reuse reserved identifiers, you can cause undefined behavior.

Polyspace Implementation

  • If you define a macro name that corresponds to a standard library macro, object, or function, rule 21.1 is violated.

  • The rule considers tentative definitions as definitions.

Troubleshooting

If you expect a rule violation but do not see it, refer to Diagnose Why Coding Standard Violations Do Not Appear as Expected.

Check Information

Group: Standard Libraries
Category: Required
AGC Category: Required

Version History

Introduced in R2024a

See Also

Topics