Re: Changes that should go into version 24.4

[Eli Zaretskii]

> Date: Fri, 21 Mar 2014 18:57:03 -0700
> From: Daniel Colascione <address@hidden>
> 
> It doesn't make sense that we'd fault accessing a stack slot on an
> active frame: doing so might corrupt something later, sure, but that
> stack location is valid and touching it isn't going to cause an
> immediate SIGSEGV.

Crashes in mark_object usually have nothing to do with accessing a
stack slot per se.  mark_object looks at the object type, and then
extracts a pointer to a C structure from it, and proceeds treating
that pointer as a valid pointer to a valid structure of that type.  If
pointer it extracts is invalid, or points to something that is not a C
struct of the type mark_object expects, we will segfault trying to
interpret those.