gdb doc

gdb doc

[A Soare]

I do not find in documentation how can I set a condition for gdb to stop to a breakpoint in Feval when such a condition is accomplished:

1. lisp function name that is evaluated is "+".

or

2. number of arguments is eq with 10.

Thanks.

Re: gdb doc

[Eli Zaretskii]

> From: A Soare <alinsoar@voila.fr>
> Date: Wed, 21 Mar 2007 14:39:27 +0100 (CET)
> 
> I do not find in documentation how can I set a condition for gdb to stop to a breakpoint in Feval when such a condition is accomplished:
> 
> 1. lisp function name that is evaluated is "+".

Compare the car of the Feval's argument with Qplus.

> 2. number of arguments is eq with 10.

Try calling Flength on the cdr of the Feval's arguments, and compare
the result with 10.

Re: gdb doc

[A Soare]

> > I do not find in documentation how can I set a condition for gdb to stop to a breakpoint in Feval when such a condition is accomplished:
> > 
> > 1. lisp function name that is evaluated is "+".
> 
> Compare the car of the Feval's argument with Qplus.
> 
> > 2. number of arguments is eq with 10.
> 
> Try calling Flength on the cdr of the Feval's arguments, and compare
> the result with 10.


Thanks

Re: gdb doc

[A Soare]

> > I do not find in documentation how can I set a condition for gdb to stop to a breakpoint in Feval when such a condition is accomplished:
> > 
> > 1. lisp function name that is evaluated is "+".
> 
> Compare the car of the Feval's argument with Qplus.


I tried t

(gdb) br Feval
Breakpoint 3 at 0x8152849: file eval.c, line 2205.o do so:
(gdb) r
Starting program: /mnt/gnu/emacs/src/emacs -geometry 80x40+0+0
[Thread debugging using libthread_db enabled]
[New Thread -1208109376 (LWP 2650)]
[Switching to Thread -1208109376 (LWP 2650)]
Breakpoint 4 at 0x80c88e6: file xterm.c, line 7859.

Breakpoint 3, Feval (form=139269229) at eval.c:2205
(gdb) p form
$1 = 139269229
(gdb) xcar form
$2 = 0x8540b91

Now I wish to do 

(gdb) commands

and here I do not know how to write CONDITION in

  if <CONDITION>
    break
  end
  continue
end

Can you help me a little mode to write the condition please?

Re: gdb doc

[A Soare]

> > I do not find in documentation how can I set a condition for gdb to stop to a breakpoint in Feval when such a condition is accomplished:
> > 
> > 1. lisp function name that is evaluated is "+".
> 
> Compare the car of the Feval's argument with Qplus.


I tried t

(gdb) br Feval
Breakpoint 3 at 0x8152849: file eval.c, line 2205.o do so:
(gdb) r
Starting program: /mnt/gnu/emacs/src/emacs -geometry 80x40+0+0
[Thread debugging using libthread_db enabled]
[New Thread -1208109376 (LWP 2650)]
[Switching to Thread -1208109376 (LWP 2650)]
Breakpoint 4 at 0x80c88e6: file xterm.c, line 7859.

Breakpoint 3, Feval (form=139269229) at eval.c:2205
(gdb) p form
$1 = 139269229
(gdb) xcar form
$2 = 0x8540b91

Now I wish to do 

(gdb) commands

and here I do not know how to write CONDITION in

  if <CONDITION>
    break
  end
  continue
end

Can you help me a little mode to write the condition please?



Finally I got it alone...

Alin Soare

Re: gdb doc

[Richard Stallman]

    > 1. lisp function name that is evaluated is "+".

    Compare the car of the Feval's argument with Qplus.

    > 2. number of arguments is eq with 10.

    Try calling Flength on the cdr of the Feval's arguments, and compare
    the result with 10.

Those are good examples for teaching people how to
take advantage of these features.
How about adding these examples to etc/DEBUG?

Re: gdb doc

[Eli Zaretskii]

> From: A Soare <alinsoar@voila.fr>
> Cc: "Emacs   Dev  [emacs-devel]" <emacs-devel@gnu.org>,
> 	"Emacs   Help  [help-gnu-emacs]" <help-gnu-emacs@gnu.org>
> Date: Thu, 22 Mar 2007 12:59:11 +0100 (CET)
> 
> Breakpoint 3, Feval (form=139269229) at eval.c:2205
> (gdb) p form
> $1 = 139269229
> (gdb) xcar form
> $2 = 0x8540b91
> 
> Now I wish to do 
> 
> (gdb) commands
> 
> and here I do not know how to write CONDITION in
> 
>   if <CONDITION>
>     break

No, you need to say "break Feval if <CONDITION>".

> Can you help me a little mode to write the condition please?

I don't have time to write and test a complete script, sorry.  You
will need to look in lisp.h for the definition of the XCAR macro, or
in src/.gdbinit for the definition of `xcar', and use the same
expressions in the condition.  Something like the following
(untested!):

  break Feval if ((struct Lisp_Cons *) ((gdb_use_union ? form.u.val : form & $valmask) | gdb_data_seg_bits))->car == Qplus

Re: gdb doc

[A Soare]

 > and here I do not know how to write CONDITION in
 >
 >   if <CONDITION>
 >     break

 No, you need to say "break Feval if <CONDITION>".

 > Can you help me a little mode to write the condition please?

 I don't have time to write and test a complete script, sorry.  You
 will need to look in lisp.h for the definition of the XCAR macro, or
 in src/.gdbinit for the definition of `xcar', and use the same
 expressions in the condition.  Something like the following
 (untested!):

   break Feval if ((struct Lisp_Cons *) ((gdb_use_union ? form.u.val : form & $valmask) | gdb_data_seg_bits))->car == Qplus


Thanks a lot.


Alin Soare.

Re: gdb doc

[A Soare]

> Message du 22/03/07 à 16h40
> De : "Richard Stallman" <rms@gnu.org>
> A : "Eli Zaretskii" <eliz@gnu.org>
> Copie à : alinsoar@voila.fr, emacs-devel@gnu.org
> Objet : Re: gdb doc
> 
>     > 1. lisp function name that is evaluated is "+".
> 
>     Compare the car of the Feval's argument with Qplus.
> 
>     > 2. number of arguments is eq with 10.
> 
>     Try calling Flength on the cdr of the Feval's arguments, and compare
>     the result with 10.
> 
> Those are good examples for teaching people how to
> take advantage of these features.
> How about adding these examples to etc/DEBUG?
> 
> 

When I clarify some many problems about debugging Feval I will add the documentation in etc/DEBUG and maybe a code in src/.gdbinit.