On the other core dumps, I'm not sure what is going on but make sure
the repo and the source tree is fully owned by the user (you or root)
doing the git operations.
I don't rebase often myself.
One possibility is that the pthreads per-thread stack is too small,
and the complexity of the operation is blowing it out. Git appears to
set the stack size to 65536 bytes (the default is ~1MB). If so this
would be a bug in git.
DragonFly creates a stack guard at the bottom of every thread stack
so it might be catching a condition that other OSs are not.
-Matt
