bug#20703: 24.4; Stack overflow in regexp matcher

[Dmitry Gutov]

Please keep the bug address in Cc.

On 06/01/2015 09:03 PM, lee wrote:

> > What if you try `M-x find-tag'?
>
> That works.

What if you type `M-x find-tag TAB' (to ask Emacs for all available tags)?

> I cut off roughly the bottom half of the TAGS file and tried again. With
> that, I'm getting the error when progress is at 85% instead of
> 42%. Cutting off the bottom half again, leaving about 1/4 of the
> original file, does not yield an error and says no matching tags were
> found.

The idea was to split the file in half, and do a sort of binary search. 
E.g., try cutting off the top half in the first step now.

> So I guess the problem might have to do with the size of the TAGS file
> ...

Not necessarily. The TAGS file is parsed sequentially, without recursion 
in the Lisp code.

In all likelihood, there is a problematic line around 42% of the 
original TAGS, and the error goes away when that line is not in the file 
anymore.

We need to know that line to fix the bug.