Ubuntu Wiki

This document describes how to install debug packages on Ubuntu, which will aid in providing information for bugs.

Feisty Fawn 7.04 and Gutsy Gibbon 7.10

Use this section only if you are using Ubuntu Feisty 7.04 or Gutsy 7.10. See the following section if you are using a prior version.

1. Add the following lines to /etc/apt/sources.list: (of course, replace gutsy by feisty if you're using 7.04)

• {{{deb http://people.ubuntu.com/~pitti/ddebs gutsy main universe

deb http://people.ubuntu.com/~pitti/ddebs gutsy-updates main universe deb http://people.ubuntu.com/~pitti/ddebs gutsy-proposed main universe deb http://people.ubuntu.com/~pitti/ddebs gutsy-security main universe }}}

2. Then run

• sudo apt-get update

to update your package list.

3. The debug symbol packages have the '-dbgsym' suffix attached, so to install the debug symbols for the package 'yelp', you run:

• sudo apt-get install yelp-dbgsym

Alternatively, main Ubuntu repositories could contain '-dbg' debug symbol packages. Those are equivalent to '-dbgsym'. You could use the one you want, but not both.

1. Now you make a ["Backtrace"].
2. You can also run ["Valgrind"], if the program crashes with a "Segmentation fault" or "Bus error".
3. Optionally, you may be asked to produce an ["Strace"].

References

• Announcement: https://lists.ubuntu.com/archives/ubuntu-devel-announce/2006-September/000195.html

Prior Ubuntu versions

Use this section if you are using an Ubuntu version prior to Feisty 7.04.

1. Check if the package has a debugging version available. In general, debugging packages will be named with a -dbg suffix

2. If not, you can generally* build one this way:

Something to keep in mind: if you would like to create a build you're going to need to have the relevant deb-src lines in your /etc/apt/sources.list

1. Install the development scripts:

   sudo apt-get install devscripts fakeroot

2. Find out to which package your program belongs to:

   dpkg --search <program> 

3. Install the build-time dependencies for the package:

   sudo apt-get build-dep <package>

4. Build .debs for debugging:

   export DEB_BUILD_OPTIONS="debug nostrip noopt"
   fakeroot apt-get source -b <package>

5. Install the needed .debs (they will be in the current working directory if the build succeeded):

   sudo debi <package>*.changes

* Most packages support the build of debugging version in this way. If this process doesn't work for a package, please open a bug against it.

The Xorg server

The X server will by default trap its own crashes and dump a stack trace in /var/log/Xorg.0.log. However, this stack trace is modified by the signal handler itself. To get a "normal" crash, which will trigger a core dump (and apport reporting), add this to your /etc/X11/xorg.conf:

Section "ServerFlags"
        Option "NoTrapSignals" "true"
EndSection

Info for the BugSquad

If you're trying to apport-retrace a crash report from a bug that didn't happen on the same Ubuntu release as the one you're running, do the following:

Say that you're running feisty and the crash happened on edgy:

1. This will create a minimal edgy system.

   sudo mkdir -p /chroots/edgy
   sudo debootstrap edgy /chroots/edgy/

2. Now you change into this minimal edgy system.

   sudo chroot /chroot/edgy

3. edit /etc/apt/sources/list and all the repositories you need, especially Martin's ddeb repository.

4. apt-get update; apt-get install gdb apport

5. use apport-retrace as you're used to.

CategoryBugSquad