Re: cperl-mode "fatigue"

[Ilya Zakharevich]

[A complimentary Cc of this posting was sent to
Stefan Monnier 
<foo@acm.com>], who wrote in article <5ld6ptz0r8.fsf@rum.cs.yale.edu>:
> >>>>> "Da" == Da Witch <heather710101@yahoo.com> writes:
> > I've noticed that sometimes, especially after I have been editing a
> > buffer for a long time, or if I try to use "qw( ... )", cperl-mode
> > begins to show signs of "fatigue" (for lack of a better word).  For
> > example, syntax-based highlighting stops, and everything I type
> > appears in the default foreground text color; or else everything
> > appears in the color reserved for quoted strings.
> 
> It's probably a bug in CPerl which raises a signal during font-locking
> and which in turn turns off on-the-fly fontification.

And due to an incredible design flaw, no message about this is emited.
This (and other flaws in the debugger w.r.t. "wrapping" exceptions)
makes debugging the situation *very* hard.  Several years ago I fixed
one of such problems; it took *hours* to find the problematic place.

> Upgrading cperl-mode might/should fix it.

The fix was available all these years, but Emacs was shipping with a
broken version nevertheless.  I think one in 21 is updated at last;
but of course, one cannot exclude a possibility of another bug.

BTW, to "restart", M-x normal-mode is enough.

Hope this helps,
Ilya