[segfaultbuserr]

> I'd suggest putting the testcase output directory on a spinning-rust hard drive that you don't care about instead of your (presumably much more expensive) internal SSD.

Even better, use the /dev/shm RAM disk if your memory is more than enough (although you should probably create an additional RAM disk with a size limit if you don't want a runaway program to accidentally drain your RAM). On a modern development machine, taking 2 GiB out for testcase issue is usually not a problem, and there's often a significant acceleration.