redeclaration of enumerator

Question

Hello,

gcc 4.1.2 c99

I have the following enum's in this file ccsmd.h :

enum options_e
{
    acm = 0,
    anm,
    smd,
    OPTIONS_LAST_ENTRY,

    OPTIONS_ENTRY_COUNT = OPTIONS_LAST_ENTRY
};

enum function_mode_e
{
    play = 0,
    record,
    bridge,
    MODE_LAST_ENTRY,

    MODE_ENTRY_COUNT = MODE_LAST_ENTRY
};

error: redeclaration of enumerator ‘LAST_ENTRY’
error: previous definition of ‘LAST_ENTRY’ was here
error: redeclaration of enumerator ‘ENTRY_COUNT’
error: previous definition of ‘ENTRY_COUNT’ was here

I have the LAST_ENTRY so that I can use that as the index of an array. So I like to keep it the same across all enums.

Many thanks for any advice,

Answer 1

Changed the prefixed the elements with the name of the enum.

Answer 2

Enumeration values exist in the same namespace as the enumeration is defined. That is, in regards to LAST_ENTRY, it's similar (used very loosely here) to:

enum options_e { /* ... */ );

// for the LAST_ENTRY value in options_e
static const int LAST_ENTRY = /* whatever */;

enum function_mode_e { /* ... */ );

// for the LAST_ENTRY value in function_mode_e
static const int LAST_ENTRY = /* whatever */;

As you can see, you're redefining LAST_ENTRY, hence the error. It's better to prefix your enum values with something to differentiate them:

enum options_e
{
    options_e_acm = 0,
    options_e_anm,
    options_e_smd,
    options_e_LAST_ENTRY,
    options_e_ENTRY_COUNT = options_e_LAST_ENTRY // note this is redundant 
};

enum function_mode_e
{
    function_mode_e_play = 0,
    function_mode_e_record,
    function_mode_e_bridge,
    function_mode_e_LAST_ENTRY,

    function_mode_e_ENTRY_COUNT = function_mode_e_LAST_ENTRY
};

Though now you lose whatever you were going for before. (Could you clarify what that was?)