Explain <package>-dbgsym Debian packages

these are a necessary tools for getting meaningful backtraces and are built by default nowadays but we should explain that

• they exist
• they do end up in the pureos archive
• one needs to enable a separate /etc/apt/sources.list entry
• the caveat that for amber-phone the entry is currently:

amber-phone

cat <<EOF > /etc/apt/sources.list.d/debug.list
deb https://repo.pureos.net/pureos-debug/ amber-debug main
deb https://repo.pureos.net/pureos-debug/ amber-proposed-updates-debug main
deb https://repo.pureos.net/pureos-debug amber-phone-staging-debug main
EOF

apt update

apt install systemd-coredump gdb calls-dbgsym chatty-dbgsym libglib2.0-0-dbgsym libgtk-3-0-dbgsym phoc-dbgsym phosh-dbgsym squeekboard-dbgsym

(note the staging there).

byzantium

cat <<EOF > /etc/apt/sources.list.d/debug.list
deb https://repo.pureos.net/pureos-debug/ byzantium-debug main
deb https://repo.pureos.net/pureos-debug/ landing-debug main
deb http://debug.mirrors.debian.org/debian-debug/ testing-debug main
EOF

apt update

apt install systemd-coredump gdb calls-dbgsym libglib2.0-0-dbgsym libgtk-3-0-dbgsym phoc-dbgsym phosh-dbgsym```

(dropped chatty and squeeboard since they're outdated in byzantium)

Usage

• how they're used with coredumpctl/gdb

This could go to a Creating meaningful coredump section at https://developer.puri.sm/Librem5/Development_Environment/Boards/Troubleshooting/Debugging.html?highlight=coredumpctl#finding-core-dumps