GDB not showing local-to-block variables ?

GDB not showing local-to-block variables ?

[Iztok Kobal]

System: i686, SuSE 8.1, kernel 2.4.19, gcc-3.2, gdb-5.2.1

code is configured to use exceptions and compiled using the 
--enable-debug. When invoking the gdb, it does not show the variables 
which are local to the block within some function:

void function (some argument) {
  try {
         some variable;     // which is not displayed by the debugger
         .....
         ......
  }
  catch (...) {
      ....
  }
}

When trying to display this variable as it was the watch variable, the 
debugger reports that there is no such symbol in the current stack frame.

Is this the debugger problem or there is an option to be used at compile 
time to get this info ?

Re: GDB not showing local-to-block variables ?

[Iztok Kobal]

Iztok Kobal wrote:

> When invoking the gdb, it does not show the variables which are local 
> to the block within some function:

I know a little more: this reffers to debugging the shared object's 
exported function and the GDB does not show any of the local-to-function 
variables, only function arguments.

I.

Re: GDB not showing local-to-block variables ?

[Iztok Kobal]

Well, I've built the sample project which demonstrates my problems.

I need somebody to look at it - please contact me and I will send it 
directly since it is too large for the maillist.

I.

Re: GDB not showing local-to-block variables ?

[Elena Zannoni]

Iztok Kobal writes:
 > System: i686, SuSE 8.1, kernel 2.4.19, gcc-3.2, gdb-5.2.1
 > 
 > code is configured to use exceptions and compiled using the 
 > --enable-debug. When invoking the gdb, it does not show the variables 
 > which are local to the block within some function:
 > 
 > void function (some argument) {
 >   try {
 >          some variable;     // which is not displayed by the debugger
 >          .....
 >          ......
 >   }
 >   catch (...) {
 >       ....
 >   }
 > }
 > 
 > When trying to display this variable as it was the watch variable, the 
 > debugger reports that there is no such symbol in the current stack frame.
 > 
 > Is this the debugger problem or there is an option to be used at compile 
 > time to get this info ?
 > 

I think this is the same problem as the one in 
http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=833

and it is due to gdb not understanding dwarf2 debug info that is
stored in .debug_ranges sections.

Elena

Re: GDB not showing local-to-block variables ?

[Iztok Kobal]

Elena Zannoni wrote:

>Iztok Kobal writes:
> > System: i686, SuSE 8.1, kernel 2.4.19, gcc-3.2, gdb-5.2.1
> > 
> > code is configured to use exceptions and compiled using the 
> > --enable-debug. When invoking the gdb, it does not show the variables 
> > which are local to the block within some function:
> > 
> > void function (some argument) {
> >   try {
> >          some variable;     // which is not displayed by the debugger
> >          .....
> >          ......
> >   }
> >   catch (...) {
> >       ....
> >   }
> > }
> > 
> > When trying to display this variable as it was the watch variable, the 
> > debugger reports that there is no such symbol in the current stack frame.
> > 
> > Is this the debugger problem or there is an option to be used at compile 
> > time to get this info ?
> > 
>
>I think this is the same problem as the one in 
>http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=833
>
>and it is due to gdb not understanding dwarf2 debug info that is
>stored in .debug_ranges sections.
>  
>
Jesus ! And only one answer posted on known thing ?

Thank you, Elena !

So what to do in my case now ? I have projects reverted from gcc-2.95 
and old automake/autoconf because I have believed that gcc-3.2/gdb-5.2.x 
is better combination !

1. Revert to use of the gcc-2.95/gdb3/4 or what ?
2. Put all kinds of outputs throughout the tons of the shared libs to 
make the debugging stoneage way ?
3. Or somebody (maybe A.Cagney) will appoint me to the right solution - 
I really doubt that there is no one !


Is this behaviour also the case with the gdb-5.3 ? I have tried to 
compile it with my gcc-3.2 and it requests the libterm library which I 
do not have in my SuSE 8.1 distro. I will not even try again if this 
mess with the debugging info is the same in gdb-5.3 !

I.

>Elena
>
>.
>
>  
>


-- 
Iztok Kobal
Iskra SISTEMI, d.d.
Stegne 21
1000 Ljubljana
Tel.: +386 (0)1 5004368
Fax.: +386 (0)1 5111283
E-mail: iztok.kobal@iskrasistemi.si
WWW: www.iskrasistemi.si

Re: GDB not showing local-to-block variables ?

[Iztok Kobal]

For information:

I have also tried to compile with the -ggdb and/or -gstabs+ options 
without any success.

I.

Re: GDB not showing local-to-block variables ?

[Iztok Kobal]

Iztok Kobal wrote:

> For information:
>
> I have also tried to compile with the -ggdb and/or -gstabs+ options 
> without any success. 

False information - the -gstabs+ does its job with misinterpretation of 
the local/argument variable role in certain cases - but at least all are 
watchable !

To the GDB community - the answer has came from the experts-exchange 
community and (shame on you since it is simple) not from you !

Regards and off !

I.

>
>
> I.
>
>
> .
>

Re: GDB not showing local-to-block variables ?

[Joel Brobecker]

Iztok Kobal,
> To the GDB community - the answer has came from the experts-exchange 
> community and (shame on you since it is simple) not from you !

I missed some of the discussion. What is this "experts-exchange
community"?

BTW: I sense a bit of disdain in your answer - I sincerly hope that this
is because I am not a native english speaker and misunderstood you.  I
personally have a lot of respect for the GDB developpers who spend some
of their time helping others for free despite the fact that they are
very busy (and there are many who do).

-- 
Joel