Re: Stack overflow in regexp matcher

[Eli Zaretskii]

> From: Stephen Berman <stephen.berman@gmx.net>
> Date: Sun, 06 Feb 2011 14:31:43 +0100
> 
> On Sun, 06 Feb 2011 10:47:42 +0000 Dan Davison <dandavison7@gmail.com> wrote:
> 
> > The following fails with "Stack overflow in regexp matcher" in emacs 23
> > and 24:
> >
> > (string-match
> >  "^\\[.+\\]$"
> >  (concat
> >   "["
> >   (mapconcat (lambda (i) "x") (number-sequence 1 33500) "")
> >   "]"))
> >
> > This surprised me; I assumed that the ^ and $ anchors, and the simple
> > ".+" requirement in the middle would result in a simple, efficient
> > regexp.
> 
> It does not fail on my GNU Emacs 24.0.50.1 (i686-pc-linux-gnu, GTK+
> Version 2.20.1) of 2011-01-13, but returns, as expected, 0.

Nor does it fail here:

   GNU Emacs 23.2.91.1 (i386-mingw-nt5.1.2600) of 2010-12-11 on 3249CTO

but does enter the debugger here:

   GNU Emacs 23.2.93.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.20.1) of 
2011-02-03 on fencepost

I guess it depends on how large is the available stack space.