bug#15778: 24.3; cperl-mode causes emacs to lock up

[Stephen Berman]

On Sun, 03 Nov 2013 07:00:51 -0500 Nathan Trapuzzano <nbtrap@nbtrap.com> wrote:

> Stephen Berman <stephen.berman@gmx.net> writes:
>
>> Well, I rebuilt (with make bootstrap) from the current truck (bzr
>> 114907), and still get the infloop from -Q with the OP's recipe minus
>> the defalias.
>
> Same here.  The defalias should not be making a difference.
>
> I'm having a really hard time debugging this with Edebug.  After I
> instrument the function (cperl-font-lock-fontify-region-function), the
> debugger is still not invoked when the function is entered.  If I add an
> explicit call to (edebug), it breaks correctly, but when I try to step
> past it, the debugger just exits, and the function resumes.
>
> Anyone have a suggestion?

I also tried and failed to get Edebug to kick in here, but I did make an
observation that surprised me but I assume is somehow relevant: if I
start Emacs with -Q, insert your sample perl code in a new buffer,
invoke cperl-mode, go to line 44 and type C-k, Emacs hangs, as you
discovered -- but if, after starting with -Q and inserting the sample
code I first invoke perl-mode and after the buffer fontifies invoke
cperl-mode, now when I go to line 44, C-k kills the line as it should
and there is no other problem, even if I then change the buffer to some
other mode and then back to cperl-mode again.

Steve Berman