bug#27585: segfault when evaluating a file containing only backticks

[Eli Zaretskii]

> From: Steve Kemp <steve@steve.org.uk>
> Date: Wed, 05 Jul 2017 18:55:31 +0000
> 
> > See above: the machinery to try and prevent it exists, but it doesn't
> > always succeed.  And it really can't be 100% reliable.  So I'm unsure
> > what did you expect, and why.
> 
>   Honestly?  I expect Emacs to not crash.

You wrote a program that triggers infinite recursion.  Such programs
will crash in most, if not all, languages.  So your expectations are
unrealistic.

>  I expect evaluating lisp to not kill the editor

Valid Lisp, I agree.  But yours isn't.

Moreover, there are those among us (I'm not one of them) who thinks
Emacs shouldn't even try to recover from stack overflow, they say it
should crash hard right there and then.

So your expectations are not necessarily shared, even as aspirations,
by some developers.

> > IOW: why would someone want to run such a silly "program"?
> 
>   In the real world?  Nobody.

Then why are we discussing this use case?  Let's talk about
more practical and interesting cases.