forward declaration for typedef of unnamed structs

[Jordi Vilar]

Hi all,

Is it possible to do a forward declaration for a typedef of an
incomplete anonymous struct? for example, if I have a type declared
(in a 3rd part header file that I cannot modify) as:

typedef struct
{
...
} mytype;

how can I forward declare such mytype type?

thanks in advance,

Jordi Vilar

 

[Peter Pichler]

Is it possible to do a forward declaration for a typedef of an
incomplete anonymous struct? for example, if I have a type declared
(in a 3rd part header file that I cannot modify) as:

typedef struct
{
...
} mytype;

how can I forward declare such mytype type?

You could if the structure had a tag. You are in bad luck with anonymous
structures. One more reason to avoid typedefing structures.

Peter

 

[Jonathan Turkanis]

You could if the structure had a tag. You are in bad luck with anonymous
structures. One more reason to avoid typedefing structures.

At best, this is one more reason to avoid anonymous structures.

Jonathan

 

[Squider]

Hi all,

Is it possible to do a forward declaration for a typedef of an
incomplete anonymous struct? for example, if I have a type declared
(in a 3rd part header file that I cannot modify) as:

typedef struct
{
...
} mytype;

how can I forward declare such mytype type?

thanks in advance,

Jordi Vilar

Maybe the author had something that seemed to be a good reason to
make it anonymous and to have only one of them running around.

 

[Derk Gwen]

(e-mail address removed) (Jordi Vilar) wrote:
# Hi all,
#
# Is it possible to do a forward declaration for a typedef of an
# incomplete anonymous struct? for example, if I have a type declared
# (in a 3rd part header file that I cannot modify) as:
#
# typedef struct
# {
# ...
# } mytype;
#
# how can I forward declare such mytype type?

typedef struct A A;
typedef struct B B;

struct A {
B *b;
};
struct B {
A *a;
};

 

[Jonathan Turkanis]

(e-mail address removed) (Jordi Vilar) wrote:
# Hi all,
#
# Is it possible to do a forward declaration for a typedef of an
# incomplete anonymous struct? for example, if I have a type declared
# (in a 3rd part header file that I cannot modify) as:
#
# typedef struct
# {
# ...
# } mytype;
#
# how can I forward declare such mytype type?

typedef struct A A;
typedef struct B B;

struct A {
B *b;
};
struct B {
A *a;
};

How does this solve the original problem?

Jonathan