Hello! After applying the same fix as in #22120, that is, binding gc-cons-threshold to most-positive-fixnum, the crashes have not reoccurred. That is, the two bugs refer to the same problem. I do not know how GC works in Emacs Lisp, but it seems to me that an Emacs Lisp program should not be able to segfault Emacs in this manner. It is interesting that this problem was introduced sometime after 19efb9 – an Emacs built from that commit did not exhibit the problem. Hope this helps, Jorgen