gdb backtrace include library as well as symbol name

gdb backtrace include library as well as symbol name

[Jon Grant]

Hello

Is there a way to get the "bt" command to output the library or ELF 
binary file that the symbol orginates in? Would be handy if this could 
even be the default:

Short example follows where I kill a process to show the backtrace 
feature in use on my Ubuntu machine.

GNU gdb (Ubuntu/Linaro 7.2-1ubuntu11) 7.2


$ ulimit -c unlimited

$ /usr/bin/totem &
[1] 3581

$ kill -11 3581
[1]+  Segmentation fault      (core dumped) totem
$ gdb /usr/bin/totem core


<snip>
Core was generated by `totem'.
Program terminated with signal 11, Segmentation fault.
#0  0xb7817424 in __kernel_vsyscall ()
(gdb) bt
#0  0xb7773424 in __kernel_vsyscall ()
#1  0xb665ff76 in poll () from /lib/i386-linux-gnu/libc.so.6
#2  0xb688084b in g_poll () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0xb68701af in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0xb687092b in g_main_loop_run () from 
/lib/i386-linux-gnu/libglib-2.0.so.0
#5  0xb6e6bc39 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0
#6  0xb77ada5f in main ()


#0 Doesn't show lib. I think this is glibc.

#6 Doesn't show the totem binary "/usr/bin/totem"

Please include my email address in any replies.

Best regards, Jon

Re: gdb backtrace include library as well as symbol name

[Jan Kratochvil]

On Mon, 26 Sep 2011 00:29:50 +0200, Jon Grant wrote:
> Is there a way to get the "bt" command to output the library or ELF
> binary file that the symbol orginates in? Would be handy if this
> could even be the default:

Yes, this is common RFE.  It was discussed in the thread:
	Re: [patch] GDB 7.2: new feature for "backtrace" that cuts path to file (remain filename)
	http://sourceware.org/ml/gdb-patches/2011-07/msg00796.html


> #0  0xb7773424 in __kernel_vsyscall ()
> #0 Doesn't show lib. I think this is glibc.

It is Linux kernel provided [vdso], it has DWARF info.


Regards,
Jan

Re: gdb backtrace include library as well as symbol name

[Joel Brobecker]

> > Is there a way to get the "bt" command to output the library or ELF
> > binary file that the symbol orginates in? Would be handy if this
> > could even be the default:
> 
> Yes, this is common RFE.  It was discussed in the thread:
> 	Re: [patch] GDB 7.2: new feature for "backtrace" that cuts path to file (remain filename)
> 	http://sourceware.org/ml/gdb-patches/2011-07/msg00796.html

I understood that thread as being something slightly different.
But what's being asked here is that the name of the exe being
debugged be printed for symbols in the main exe. This is the only
time as far as I known when the name of the objfile is not
printed, so I think that the current output is fine.

There has been a project of decorated backtraces, which allows
a user to enhance them via Python. Have you looked at this project?
Not sure if this project made it to the main repository, of if
it is still only in Archer, though.

> > #0  0xb7773424 in __kernel_vsyscall ()
> > #0 Doesn't show lib. I think this is glibc.
> 
> It is Linux kernel provided [vdso], it has DWARF info.

To complete what Jan said, it is in memory, but does not have
a corresponding file.

-- 
Joel

Re: gdb backtrace include library as well as symbol name

[Tom Tromey]

>>>>> "Joel" == Joel Brobecker <brobecker@adacore.com> writes:

Jan> Yes, this is common RFE.  It was discussed in the thread:
Jan> Re: [patch] GDB 7.2: new feature for "backtrace" that cuts
Jan> path to file (remain filename)
Jan> http://sourceware.org/ml/gdb-patches/2011-07/msg00796.html

Joel> I understood that thread as being something slightly different.
Joel> But what's being asked here is that the name of the exe being
Joel> debugged be printed for symbols in the main exe. This is the only
Joel> time as far as I known when the name of the objfile is not
Joel> printed, so I think that the current output is fine.

I think it would be a decent addition.

What happened to the patch which Jan references?  It also seemed like a
good idea, or at least a good one once minor changes were made.

Joel> There has been a project of decorated backtraces, which allows
Joel> a user to enhance them via Python. Have you looked at this project?
Joel> Not sure if this project made it to the main repository, of if
Joel> it is still only in Archer, though.

Phil is reimplementing this in a better way.

Tom