How can I prevent my system from trying to start gdb in case of SIGSEGV? I want my application to die properly, so the return of the process can be caught and errors (if any) handled properly.
Caught SIGSEGV exec gdb failed: No such file or directory Spinning. Please run 'gdb gst-launch-1.0 1586' to continue debugging, Ctrl-C to quit, or Ctrl-\ to dump core. ^C|^\Quit
A GStreamer program that is started by gst-launch will, by default, install a fault handler function as the signal handler for SIGSEGV and SIGQUIT. When either of those signals arrive, the program will run GDB to display a stack trace - in your case, GDB wasn't found - then go into a low-overhead spin loop while waiting for you to run GDB manually. (Source code.)
You can prevent the fault handler from being installed by giving gst-launch the --no-fault or -f option.