Are you actually getting a warning about this one or is this just a style change you are proposing? When an enum is being used to represent bit flags, I have preferred to use a regular unsigned integer type instead of the enum typedef so it is clear that the value is a combination of the enumerated values instead of just a single value in the enumeration. I'd be happy to discuss if we want to change that across libgit2. However, I don't think it should be causing warnings.