Doc on error messages

Doc on error messages

[Thomas Garsiot]

Hi there,

I'm sure I'm not the first on to ask this question, but I haven't been
able to find an answer on the web, in the archives of this list or in
news groups ...

Is there any exhaustive (or at least important) documentation on GCC's
error messages ?

I found some pages on frequent error messages, but there are often only
the 5 most frequent error messages and of course ... mine is not among
them :-)
I have a "dereferencing pointer to incomplete type" error, and I have no
idea of what an incomplete type is.

Thanks in advance for directing me to a good page on error messages.

Cheers,

    Thomas

Re: Doc on error messages

[Soubhik Bhattacharya]

r u using a multi-dimensional array? 


On Mon, 26 Feb 2001, Thomas Garsiot wrote:

:Hi there,
:
:I'm sure I'm not the first on to ask this question, but I haven't been
:able to find an answer on the web, in the archives of this list or in
:news groups ...
:
:Is there any exhaustive (or at least important) documentation on GCC's
:error messages ?
:
:I found some pages on frequent error messages, but there are often only
:the 5 most frequent error messages and of course ... mine is not among
:them :-)
:I have a "dereferencing pointer to incomplete type" error, and I have no
:idea of what an incomplete type is.
:
:Thanks in advance for directing me to a good page on error messages.
:
:Cheers,
:
:    Thomas
:
:

RE: Doc on error messages

[Puneet Singhal]

Hi Thomas,

>Is there any exhaustive (or at least important) documentation on GCC's
>error messages ?
>
>I found some pages on frequent error messages, but there are often only
>the 5 most frequent error messages and of course ... mine is not among
>them :-)
>I have a "dereferencing pointer to incomplete type" error, and I have no
>idea of what an incomplete type is.

Send the code which gives this error.
And the exact error message that gcc gives.

I am not aware of any errors page but I can help u with this one.

;-)
Puneet aka Victor

Re: Doc on error messages

[Thomas Garsiot]

Here are the details of the code you requested :

actually this is some code extracted from UCD-SNMP :

struct sockaddr_in *pduIp;
struct snmp_pdu *template_pdu;


pduIp = (struct sockaddr_in *)&(template_pdu->agent_addr);
pduIp->sin_family   = AF_INET;



----------------------------------
type definitions :
#define _UCD_SS_MAXSIZE   92  /* <= sizeof( sockaddr_un ) */
#define _UCD_SS_ALIGNSIZE (sizeof (long))

#define _UCD_SS_PAD1SIZE  (_UCD_SS_ALIGNSIZE - sizeof( unsigned short ))
#define _UCD_SS_PAD2SIZE  (_UCD_SS_MAXSIZE - \
  (sizeof( unsigned short ) + _UCD_SS_PAD1SIZE + _UCD_SS_ALIGNSIZE ))
typedef struct {
    unsigned char sa_len;
    unsigned char sa_family;

    char  sa_data[ _UCD_SS_PAD1SIZE ];
    long  sa_align;
    char  sa_pad2[ _UCD_SS_PAD2SIZE ];

} snmp_ipaddr;

struct snmp_pdu {
[...]
    snmp_ipaddr agent_addr;
[...]
 };


-----------------
/*
 * Socket address, internet style.
 */
struct sockaddr_in {
 u_char sin_len;
 u_char sin_family;
 u_short sin_port;
 struct in_addr sin_addr;
 char sin_zero[8];
};
struct in_addr {
 u_long s_addr;
};

I tried to include only the useful part.  Sorry if it's a little messy.

Thanks in advance for your help.

Cheers,

    Thomas

Re: Doc on error messages

[Alexandre Oliva]

On Feb 26, 2001, Thomas Garsiot <garsiot@st2e.com> wrote:

> I have a "dereferencing pointer to incomplete type" error, and I have no
> idea of what an incomplete type is.

An incomplete type is one that has been declared but not defined.  For
example, a forward-declared struct is an incomplete type before it is
actually given a definition.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me

Re: Doc on error messages --More questions on error messages

[sherry]

So, there is no doc/page/info on error messages ?

I have seen an error that says:
looser throw specifier for virtual `foo`
And that happens when the base class has a throw() spec while the derived
class does not.

But why is this an error?


Alexandre Oliva wrote:

> On Feb 26, 2001, Thomas Garsiot <garsiot@st2e.com> wrote:
>
> > I have a "dereferencing pointer to incomplete type" error, and I have no
> > idea of what an incomplete type is.
>
> An incomplete type is one that has been declared but not defined.  For
> example, a forward-declared struct is an incomplete type before it is
> actually given a definition.
>
> --
> Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
> Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
> CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
> Free Software Evangelist    *Please* write to mailing lists, not to me

Re: Doc on error messages --More questions on error messages

[Alexandre Oliva]

On Feb 26, 2001, sherry <sherry@zeroknowledge.com> wrote:

> So, there is no doc/page/info on error messages ?

Yep.

> I have seen an error that says:
> looser throw specifier for virtual `foo`

> And that happens when the base class has a throw() spec while the derived
> class does not.

> But why is this an error?

Because the C++ Standard says so.

Just think of it.  Given:

base *x;
x->foo();

if you were allowed to throw exceptions not defined in the base class
interface, how would one be able to trust exception specifications?

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me