expanding backtrace

expanding backtrace

[Cameron Stone]

I'm trying to write a script to print an expanded backtrace. It's basically:

while loop_condition
	print frame
	print local variables
	print list (context)
	up-silently
end

However, I can't figure out how to implement the loop condition. All the 
functions in the manual are about how to print that information, but can't 
figure out how to get it into a variable or something that can be used to 
break the loop.

Apologies if this has already been dealt with. I couldn't find it in the list 
archives.
-- 
===================================================================

"Man is the only animal that blushes -- or needs to." - Mark Twain

Cameron Stone                            <camerons@cse.unsw.edu.au>
===================================================================

Re: expanding backtrace

[Daniel Jacobowitz]

On Tue, Jun 27, 2006 at 06:25:19PM +1000, Cameron Stone wrote:
> I'm trying to write a script to print an expanded backtrace. It's basically:
> 
> while loop_condition
> 	print frame
> 	print local variables
> 	print list (context)
> 	up-silently
> end
> 
> However, I can't figure out how to implement the loop condition. All the 
> functions in the manual are about how to print that information, but can't 
> figure out how to get it into a variable or something that can be used to 
> break the loop.

You can't; the GDB CLI just doesn't support this sort of thing. 
However, I'm vaguely hopeful that we'll have better scripting support
in time for the next release.

"while 1" might work, since the last "up" will raise an error.

"bt full" handles the frame and local variables already, btw, but I
don't think it lists.

-- 
Daniel Jacobowitz
CodeSourcery

Re: expanding backtrace

[Andrew STUBBS]

Cameron Stone wrote:
> I'm trying to write a script to print an expanded backtrace. It's basically:
> 
> while loop_condition
> 	print frame
> 	print local variables
> 	print list (context)
> 	up-silently
> end
> 
> However, I can't figure out how to implement the loop condition. All the 
> functions in the manual are about how to print that information, but can't 
> figure out how to get it into a variable or something that can be used to 
> break the loop.
> 
> Apologies if this has already been dealt with. I couldn't find it in the list 
> archives.

You could write something like

while $pc != 0

or

while $sp <= $topofmem

It depends how your backtraces end.

Re: expanding backtrace

[Nick Roberts]

 > You could write something like
 > 
 > while $pc != 0

I don't think that works.

 > or
 > 
 > while $sp <= $topofmem
 > 
 > It depends how your backtraces end.

If you mean:

  (gdb) start
  ...
  (gdb) set $topofmem=$sp

and use "$sp < $topofmem" for the loop condition, then that looks like a good
idea.

-- 
Nick                                           http://www.inet.net.nz/~nickrob