NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/comp/sys/amiga/programm/18050

Text File | 1993-01-02 | 3.0 KB | 102 lines

Newsgroups: comp.sys.amiga.programmer
Path: sparky!uunet!math.fu-berlin.de!informatik.tu-muenchen.de!rz.uni-passau.de!kirk.fmi.uni-passau.de!agsteine
From: [e-mail] (Karlheinz Agsteiner)
Subject: Re: A bug in SAS/C 6.0
Message-ID: <[e-mail]>
Sender: [e-mail] (News-Operator)
Organization: University of Passau, Germany
References:  <[e-mail]>
Date: Sat, 2 Jan 1993 15:37:15 GMT
Lines: 90

In article <[e-mail]>, [e-mail] (Timothy M. Stark) writes:
|> Hello Everyone:

Hi!

|>
|>       I discovered that bug in the compiler. I implemented a few typedef
|> statements into my program and set up double-link variables. I tried compile
|> it but it displayed the strange message error:
|>
|>       Missing closed bracket!
|>
|> This bug program:
|>
|> #include <stdio.h>
|>
|> typedef struct bug1 {
|>        bug2  *bugb;
|> } bug1;
|>
|> typedef struct bug2 {
|>        bug1  *buga;
|> } bug2;

IMHO, You're making two mistakes in Your declaration:

1) You can't use the same name with Your struct and Your typedef.
   (What You're doing is "typedef struct bug1 bug1"). Try struct _bug1
   or something like that.

2) I don't know where K&R are stating this, but I think You have to
   define every type before using it. The only exception is a
   struct <name> *  where name doesn't need to be defined. Therefore
   You should replace Your declaration by e.g.

typedef struct _bug1 {
       struct _bug2 *bugb;
} bug1;

typedef struct _bug2 {
       struct _bug1 *buga;
} bug2;

(which is how I implement crosswise linkings) or maybe

struct _bug1 {
  struct _bug2 *bugb;
}

struct _bug2 {
  struct _bug1 *buga;
}

typedef struct _bug1 bug1;
typedef struct _bug2 bug2;

These two declarations should work.

I think the compiler

|> This program cause the compiler confusing and it displayed the strange
|> message - Missing closed bracket (']'). I looked for the open bracket
|> character but it is not in my program!

I don't know why the compiler complains about a "]". I think It "hits"
the undeclared type "bug2", and thinks that this can't be probably part
of the type definition of "bug1", and therefore it should expect a "}"
here to end the definition (hoping that "bug2" makes sense outside the
definition.

Sorry for this permanent usage of both "type declaration" and
"type definition" for the same thing, but it seems that every
language uses a different term for that :)

Hope this helps. I'm sure someone here has a much more K&R - like
way to define the above, but I ran into the same problem as You
defining crosswise dependencies, and this was the solution I found.

|> -- Tim Stark
|>
|>
|> --
|> Timothy Stark               Internet1: [e-mail] (Preferred)
|> 837 North Van Dorn St       Internet2: [e-mail]
|> Alexandria, Va. 22304-2723  TDD: [phone] Pager: [phone]
|> "Washington, DC is the most deaf population!! -- Gallaudet University"

Karlheinz Agsteiner
--
e-mail: [e-mail]