Rule 13.3 incr/decr op in initialization

Rule 13.3 incr/decr op in initialization - Printable Version

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Rule 13.3 incr/decr op in initialization - delirium5223 - 04-09-2025

Based on the example in MISRA 2023 C this is non-compliant:

Code:
  int u8a=0;  // implied

  u8a = u8b++;  //don't accept assignment and increment on the same line

but what about in initialization? According to PCLP tool it's acceptable:

Code:
  int u8a = u8b++;

My view is that de/increment shouldn't be mixed with anything and it should be alone in one line to avoid any chance of confusion.

Please clarify.

RE: Rule 13.3 incr/decr op in initialization - misra-c - 20-11-2025

The examples for Rule 13.3 state:

Code:
The expression:

u8a = u8b++

is non-compliant.

The glossary also clarifies that assignment includes Using an expression to initialize all or part of an object.

From this, the intent of Rule 13.3 (Advisory) is that use of ++ in an initialization is non-compliant.