Dear spot team, I think I found a bug in spot. When I run % cat foo.hoa HOA: v1 States: 1 Start: 0 AP: 3 "l0" "l1" "l2" acc-name: generalized-Buchi 0 Acceptance: 0 t --BODY-- State: 0 [(0&1)] 0 [(2)] 0 [(!2)] 0 —-END-- %autfilt --small -S foo.hoa I get a bus error. It seems that options —small and -S are both necessary to reproduce the bug. Similarly, none of the transitions in the automaton can be removed. I am running spot version 2.11.4 on an MacBook Pro with M1 Pro CPU compiled with --disable-python. Given that this seems to be a “low-level” system error, it could very well be that it is an issue with my machine setup. In this case: Do you have any idea how to fix this? Thanks already for your help! All the best, Raven PS: The current download link for the most recent version of spot (https://spot.lre.epita.fr/install.html) claims to download version 2.11.4 but actually still points to version 2.11.3.