[Buildroot] backtrace() depth

[Buildroot] backtrace() depth

[Peter Kümmel]

I've a question about the depth of a backtrace.

I've configured uClibc/Buildroot to build libubacktrace-0.9.33.2.so
via the standard Buildroot menuconfigs:
Buildroot 2013.02, GCC 4.7.2 by Buildroot, uClibc-0.9.33

When I call backtrace() on a segfault, I only see the function
where the segfault is produced, and not much more (only /lib/libc.so.0,
and two more addresses). The function name could be demanded correctly,
so I assume the compiler flags are ok (-rdynamic).

The segfault is not in the main thread
(overall 4 threads, /lib/libpthread-0.9.33.2.so)
And the bt looks equal for debug and release builds.

A build with crosstool-ng and eglibc produces the same bad backtrace.

Is there a way to get a more complete backtrace?

Many thanks,
Peter

[Buildroot] backtrace() depth

[Samuel Martin]

Peter,


2013/9/10 Peter K?mmel <syntheticpp@gmx.net>

> I've a question about the depth of a backtrace.
>
> I've configured uClibc/Buildroot to build libubacktrace-0.9.33.2.so
> via the standard Buildroot menuconfigs:
> Buildroot 2013.02, GCC 4.7.2 by Buildroot, uClibc-0.9.33
>
> When I call backtrace() on a segfault, I only see the function
> where the segfault is produced, and not much more (only /lib/libc.so.0,
> and two more addresses). The function name could be demanded correctly,
> so I assume the compiler flags are ok (-rdynamic).
>
> The segfault is not in the main thread
> (overall 4 threads, /lib/libpthread-0.9.33.2.so)
> And the bt looks equal for debug and release builds.
>
> A build with crosstool-ng and eglibc produces the same bad backtrace.
>
> Is there a way to get a more complete backtrace?
>

Is the strip command set to none (under the "Build options" menu)?
if not, then you should certainly added the binaries you are debgging to the
BR2_STRIP_EXCLUDE_FILES or  BR2_STRIP_EXCLUDE_DIRS lists.


Regards,

-- 
Samuel
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.busybox.net/pipermail/buildroot/attachments/20130910/22183164/attachment.html>

[Buildroot] backtrace() depth

[Peter Kümmel]

>
> Is the strip command set to none (under the "Build options" menu)?
> if not, then you should certainly added the binaries you are debgging to the
> BR2_STRIP_EXCLUDE_FILES or  BR2_STRIP_EXCLUDE_DIRS lists.

Hi Samuel,

I even selected sstrip for the compiler and rootfs, but the the application
itself is not stripped, it's not build by buildroot.
Does the bt stop at the first stripped lib it reaches?

Peter