Enumeration types in C map to integers. The normal expectation is that each enumeration type member is distinct. However, there are some non-obvious nonobvious errors that are commonly made that cause multiple enumeration type members to have the same value.
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In this noncompliant code example, enumeration type members can be are assigned explicit values:
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Enumeration type declarations must eitherdo one of the following:
- provide no explicit integer assignments, as in this example:
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It is also advisable to provide a comment explaining why multiple enumeration type members are being assigned the same value so that future maintainers don't mistakenly identify this as an error.
Of these three options, the first — "provide no explicit integer assignments" — is the simplest, and consequently the preferred, approach in the typical case.
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