Subject: Re: bug#17509: 23.4; bug with regexp in java-mode

From: Stefan Monnier <[email-masked]>
Date: Fri, 16 May 2014 17:48:18 -0400

>>> (setq defun-prompt-regexp "\\(class\\|/\\*\\*\\)[^{]*")
>> Why is this an Emacs bug, and not user error?
> Because I suppose that Emacs should never hang...

FWIW, the exponential blowup that can happen in regexp matching is
indeed a misfeature of Emacs's current regexp matcher.
But it's been that way "for ever" and there's no promising sign of an
upcoming fix for it.

        Stefan