Why would an enum declaration be marked const?

Question

I saw this construct in the project I work:

const enum SomeEnum
{
    val0,
    val1,
    val2
};

What is the purpose of const here?

Answer 1

Nothing at all. Actually, according to G++ it is a compiler error:

error: qualifiers can only be specified for objects and functions

However, in C it is allowed, but useless. GCC says:

warning: useless type qualifier in empty declaration

The issue is that const only applies to objects (variables) and member functions, but not to basic types.

Answer 2

It doesn't make a difference in your code, but it would in this case:

const enum SomeEnum
{
    val0,
    val1,
    val2
} VAL0 = val0;

Here, VAL0 would be a const variable (with the value val0). TBH though, it isn't of much use.