Enum.1: Prefer enumerations over macros

Flag macros that define integer values

no enforcement

Enum.2: Use enumerations to represent sets of related named constants

Flag switch-statements where the cases cover most but not all enumerators of an enumeration.
Flag switch-statements where the cases cover a few enumerators of an enumeration, but has no default.

clang: -Wswitch

Enum.3: Prefer class enums over "plain" enums

(Simple) Warn on any non-class enum definition.

no enforcement

Enum.4: Define operations on enumerations for safe and simple use

Flag repeated expressions cast back into an enumeration.

no enforcement

Enum.5: Don't use ALL_CAPS for enumerators

Flag ALL_CAPS enumerators.

no enforcement

Enum.6: Avoid unnamed enumerations

Flag unnamed enumerations.

no enforcement

Enum.8: Specify enumerator values only when necessary

Flag duplicate enumerator values
Flag explicitly specified all-consecutive enumerator values

no enforcement