What a disaster.
I just figured that r128gain messed up some of my files in that last directory, where the coredump took place.
I've got some dead bodies called:
X92jzl.flac
kuzTIz.flac
LLQuv7.flac
One hint: It's been Hirez 24/88.2 data and 28 files in a single directory or so. Maybe there's resource issue. I do have 8GB RAM in my machine.