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MISRA C:2023 Rule 20.10

The # and ## preprocessor operators should not be used

Since R2024a

Description

Rule Definition

The # and ## preprocessor operators should not be used.

Rationale

The order of evaluation associated with multiple #, multiple ##, or a mix of # and ## preprocessor operators is unspecified. In some cases, it is therefore not possible to predict the result of macro expansion.

The use of ## can result in obscured code.

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: Preprocessing Directives
Category: Advisory
AGC Category: Advisory

Version History

Introduced in R2024a