Ok, after installing xserver-xorg-core-dbgsym and using "--callstack dwarf" it now works. This bug can be closed.
** Changed in: xorg-server (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1733697 Title: xserver-xorg-core-dbg does not provide proper debug symbols To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1733697/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs