bug#53348: 27.2; Crash in mark_object

[Eli Zaretskii]

> From: "Reingruber, Richard" <richard.reingruber@sap.com>
> CC: "53348@debbugs.gnu.org" <53348@debbugs.gnu.org>
> Date: Tue, 18 Jan 2022 17:07:53 +0000
> 
> The issue occurred today on another macbook which is x86_64 not arm64. OS and 
> emacs versions are the same.
> 
>     > Looks like C stack overflow, or at least a possibility of it (you
>     > didn't show all of the backtrace levels, so it's hard to be sure).
> 
> Yes, could be stack overflow. Is emacs' gc recursive? Will it crash if there 
> is
> a long enough list?

Yes, GC is very recursive, although it shouldn't cause stack overflow
with "usual" data structure.  No, a long list shouldn't cause such
deep recursion, but a deeply-recursive list or some other recursive
data structure could, if the depth is unusually large.