Subject: bug#21666: Bug is indeed undo-list and GC related

From: Jorgen Schäfer <[email-masked]>
Date: Wed, 09 Mar 2016 10:14:35 +0000

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