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+---- Forum: 8.8 Declarations and defnitions (https://forum.misra.org.uk/forumdisplay.php?fid=163)
+---- Thread: It 8.12 intended to be so strict? (/showthread.php?tid=1774)
It 8.12 intended to be so strict? - Loïc - 25-06-2026
Hello,
It is clear by looking at the title of rule 8.12
Quote:Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique
That the following code is non-compliant:
Code:
// Non-compliant, yellow has an implixitly defined value that it shares with last
enum colour { red, blue, green, yellow, last = yellow };This is a relatively common pattern, and the alternatives seem worse.
It is the intent of this rule to prevent this pattern, or is it just a result of the wording?
By the way, this code is compliant with the C++ version of this rule in MISRA C++:2023.
RE: It 8.12 intended to be so strict? - misra-c - 08-10-2026
The MISRA C rule 8.12 is an example of a simple deterministic rule, that traps circumstances that one might wish to permit.
The related MISRA C++:2023 rule 11.6.3 has an exception which appears to resolve the issue highlighted.
The MISRA C WG will consider adding the exception to a future update of MISRA C