has incomplete type

[onsbomma]

Can anyone tell me the difference between
typedef struct chunkinfo* mfastbinptr;

and

typedef struct chunkinfoptr chunkinfoptr;
if you know that

struct chunkinfo{
struct chunkinfo* next;
struct chunkinfo* prev;
int size;
};

typedef struct chunkinfo* chunkinfoptr;

With the second i get a "has incomplete type" error

[Thomas Matthews]

onsbomma wrote:

Can anyone tell me the difference between
typedef struct chunkinfo* mfastbinptr;

and

typedef struct chunkinfoptr chunkinfoptr;
if you know that

struct chunkinfo{
struct chunkinfo* next;
struct chunkinfo* prev;
int size;
};

typedef struct chunkinfo* chunkinfoptr; Note that the '*' means a pointer.

With the second i get a "has incomplete type" error

Let us do some simple substitutions:
The original problem line:
typedef struct chunkinfoptr chunkinfoptr;

Substitute "struct chunkinfo *" for chunkinfoptr:
typedef struct struct chunkinfoptr * chunkinfoptr;

Do you see the error?
Also, please don't use a structure tag as a type-id.
So, what are you trying to do?

Your code fragment above indicates some confusion
issues.

--
Thomas Matthews

[Eric Sosman]

onsbomma wrote:

Can anyone tell me the difference between
[...]

Please post the actual code and the actual error message.
Post a minimal but complete example that someone else could
process with a compiler. Trying to reconstruct what you were
actually doing is an error-prone process, likely to lead to
a diagnosis of a problem entirely different from the one you
are struggling with.

--
Er*********@sun .com

[leon]

There are 3 "chunkinfop tr" here in your code.

onsbomma wrote:

Can anyone tell me the difference between
typedef struct chunkinfo* mfastbinptr;

and

typedef struct chunkinfoptr chunkinfoptr;
The 1st "chunkinfop tr" is an undefined struct.
The 2nd "chunkinfop tr" is an identifier of the undefined struct.

if you know that

struct chunkinfo{
struct chunkinfo* next;
struct chunkinfo* prev;
int size;
};

typedef struct chunkinfo* chunkinfoptr; The 3rd "chunkinfop tr" is a type identifier.

With the second i get a "has incomplete type" error

The thred "chunkinfop tr" are not conflict to each other in that they
are in different namespaces (typedef, struct and identifier).

But when you try to create a variable of the 2nd "chunkinfop tr", the
compiler will compalain "incomplete type", because "struct
chunkinfoptr" is undefined.