vdr-plugin-mpv

If you are on Ubuntu Jammy (22.04) or later, you do not need to worry about installing debug symbol packages anymore. The Ubuntu project maintains a Debuginfod server, and GDB and other debuginfo-consumer applications support it out of the box. For more information about it, please refer to this page. Otherwise, if you are on an older Ubuntu release (pre-Jammy), please ensure you have packages with debug symbols installed. You can do this by following the instructions at DebuggingProgramCrash.

Make sure the GNU Debugger is installed.

sudo apt-get install gdb 
Start the program under control of gdb via a terminal (some programs run as root, so one would use sudo gdb instead of just gdb below):

gdb <program> 2>&1 | tee ~/gdb-<program>.txt
(gdb) handle SIG33 pass nostop noprint
(gdb) set pagination 0
(gdb) run <arguments, if any>
The program will start. Perform any actions necessary to reproduce the crash. If the program hangs but doesn't crash you can press ctrl+c in gdb while the program is frozen and then continue with the next step.
Retrieve a backtrace:

(gdb) backtrace full
(gdb) info registers
(gdb) x/16i $pc
(gdb) thread apply all backtrace
(gdb) quit 
Attach the complete output from GDB, contained in gdb-<program>.txt, in your bug report. You will find the file in your home directory /home/<username>/.

Already running programs
You can ask GDB to attach to a program that's already running. This is useful for debugging things that start up, but crash when you perform a particular task.

Make sure the GNU Debugger is installed.

sudo apt-get install gdb 
Find the process ID of <program>:

pidof <program> 
Start gdb (some programs run as root, so one would use sudo gdb instead of just gdb below):

gdb 2>&1 | tee gdb-<program>.txt
(gdb) handle SIG33 pass nostop noprint
(gdb) set pagination 0
(gdb) attach <PID> 
Continue the <program>:

(gdb) continue 
The program will continue running. Perform any actions necessary to reproduce the crash. If the program hangs but doesn't crash you can press ctrl+c in gdb while the program is frozen and then continue with the next step.
Retrieve a backtrace:

(gdb) backtrace full
(gdb) info registers
(gdb) x/16i $pc
(gdb) thread apply all backtrace
(gdb) quit 
Attach the complete output from GDB, contained in gdb-<program>.txt, in your bug report.

Note that you can also set logging to a file like this:

(gdb) set logging file gdb-<program>.txt
(gdb) set logging on 
Core Files
You are also able to retrace a core file if you have one produced (I believe these are disabled by default).

Load the core file into the debugger

 gdb -c <corefile> 2>&1 | tee gdb-<program>.txt 
Retrieve a backtrace of the crash:

(gdb) backtrace full
(gdb) info registers
(gdb) x/16i $pc
(gdb) thread apply all backtrace
(gdb) quit 
Attach the complete output from GDB, contained in gdb-<program>.txt, in your bug report. You will find the file in your home directory /home/<username>/.

Summary in script form
You can automate backtrace collection as described above using this Bourne shell script:

save it somewhere in your $PATH
make it executable

#---------------------------------------------------------------------
usage() {
    cat<<EOF
Usage: ${0} program_name [program_args]

Trace a given program using gdb.

EOF
}

log() {
    echo "${*}" 1>&2
}

die() {
    usage
    log 'error:' ${*}'.'
    exit 1
}
#---------------------------------------------------------------------
test "x${*}" = "x" && die 'no process given'

LOG="/tmp/gdb-`basename ${1}`.txt"
log "outputting trace to '${LOG}'"

exec gdb -batch-silent \
    -ex 'set logging overwrite on' \
    -ex "set logging file ${LOG}" \
    -ex 'set logging on' \
    -ex 'handle SIG33 pass nostop noprint' \
    -ex 'set pagination 0' \
    -ex 'run' \
    -ex 'backtrace full' \
    -ex 'info registers' \
    -ex 'x/16i $pc' \
    -ex 'thread apply all backtrace' \
    -ex 'quit' \
    --args ${*} \
    < /dev/null

# make
player.c:207:46: error: missing binary operator before token "("
  207 | #if MPV_CLIENT_API_VERSION < MPV_MAKE_VERSION(2,0)
      |                                              ^
player.c:225:46: error: missing binary operator before token "("
  225 | #if MPV_CLIENT_API_VERSION < MPV_MAKE_VERSION(2,0)
      |                                              ^
player.c:713:47: error: missing binary operator before token "("
  713 | #if MPV_CLIENT_API_VERSION >= MPV_MAKE_VERSION(2,0)
      |                                               ^
player.c:867:47: error: missing binary operator before token "("
  867 | #if MPV_CLIENT_API_VERSION >= MPV_MAKE_VERSION(1,29)
      |                                               ^
player.c:969:47: error: missing binary operator before token "("
  969 | #if MPV_CLIENT_API_VERSION >= MPV_MAKE_VERSION(2,0)
      |                                               ^
player.c:979:47: error: missing binary operator before token "("
  979 | #if MPV_CLIENT_API_VERSION >= MPV_MAKE_VERSION(2,0)
      |                                               ^
CC mpv.o
g++ -I/usr/include/libdrm -g -O3 -Wall -Werror=overloaded-virtual -Wno-parentheses -fPIC -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -Wno-switch -c -DPLUGIN_NAME_I18N='"mpv"' -D_GNU_SOURCE -DUSE_LIBMPV -DUSE_DISC -DUSE_XRANDR -DUSE_DRM  -DPLGRESDIR='"/usr/share/vdr/plugins/mpv"'  -o mpv.o mpv.c
In file included from config.h:15,
                 from mpv.c:14:
player.h:15:10: fatal error: mpv/client.h: Datei oder Verzeichnis nicht gefunden
   15 | #include <mpv/client.h>
      |          ^~~~~~~~~~~~~~
compilation terminated.
make: *** [Makefile:111: mpv.o] Fehler 1