Stack overflow in regexp matcher

[Dan Davison <dandavison7@gmail.com>]

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.

In this case I can replace this with a different test using `substring',
but I'm curious: was the above obviously unwise to someone who knows
about emacs regexps? What would be a better regexp be to use in this
sutuation?  Fwiw, The same match seems to work instantaneously in
e.g. perl.

Dan