C enum definition in struct with typedef

Question

I found some problem with definition of enum inside a struct, I want to have something like:

typedef struct
{
    typedef enum { E1, E2, E3 } E;
    E e;
} S;

in VS2012 I have errors:

error C2071: 'E' : illegal storage class
error C2061: syntax error : identifier 'E'
error C2059: syntax error : '}'

I found an explanation of C2071 but it is not the same case: http://msdn.microsoft.com/en-us/library/deb3kh5w.aspx

gcc-4.9 says:

error: expected specifier-qualifier-list before ‘typedef’

the interesting thing is that the code:

typedef enum { E1, E2, E3 } E;
E e;

works fine in global scope and in function's body.

I've also tried to do it without typedef, but unfortunately there are still lot's of errors:

error C2011: 'E' : 'enum' type redefinition
see declaration of 'E'
error C2208: 'E' : no members defined using this type

I found similar reason: http://msdn.microsoft.com/en-us/library/ms927163.aspx but I do define members of the type.

Any use of typedef in a structure declaration is a syntax error. What do you expect that code to do? If you want the typedef visible only inside the structure declaration (which isn't really useful anyway): Structure declarations don't introduce a new scope (and if they did, the enumeration constants would then be unreachable from outside the structure). — mafso
– mafso, Commented Nov 26, 2014 at 21:02

Crowman · Accepted Answer · 2014-11-26 21:01:16Z

3

You should declare your enum member like so:

typedef struct
{
    enum { E1, E2, E3 } e;
} S;

then you can do:

int main(void)
{
    S s;
    s.e = E1;

    /*  And so on  */
}

answered Nov 26, 2014 at 21:01

Crowman

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