Wanted to say THANKS for the "menu_enable_widgets" fix and to share some more info.
First, it was interesting that ROMs were fine and that ATR disks were all failing.
I tracked down the segmentation violation in the /dev/shm/run command.log:
/opt/retropie/supplementary/runcommand/runcommand.sh: line 1283: 31257 Segmentation fault /opt/retropie/emulators/retroarch/bin/retroarch -L /opt/retropie/libretrocores/lr-atari800/atari800_libretro.so --config /opt/retropie/configs/atari800/retroarch.cfg "/home/pi/RetroPie/roms/atari800/Mule.atr" --verbose --appendconfig /dev/shm/retroarch.cfg
I took a look at line 1283:
eval $COMMAND </dev/tty &>>"$LOG"
All this is doing is running the right command, explicitly getting input from the tty, and tying file descriptors to the log.
I ran the command from the console and it worked fine without redirecting STDIN/STDERR. It also worked fine just redirecting STDOUT (fd 1). But every time I redirected STDERR (fd 2), I got a segmentation violation.
Not sure what exactly the widgets have to do with this, but apparently they do. If anybody wants a strace of this I would be happy to provide.
I hope this is helpful, and again, thanks for the fix!