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From: Alan Mackenzie <acm@muc.de>
Newsgroups: gmane.emacs.devel
Subject: Re: Elusive indentation problem in CC Mode
Date: Fri, 16 Mar 2012 14:32:43 +0000
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To: Eli Zaretskii <eliz@gnu.org>
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Hello, Eli.

On Fri, Mar 16, 2012 at 11:43:40AM +0200, Eli Zaretskii wrote:
> >>From time to time, I have a strange Heisenbug when editing C source
> files: CC Mode computes the indentation level incorrectly.  The
> problem usually manifests itself by pressing TAB and having the
> current line be flushed all the way to the left, as if point is at
> toplevel (which it isn't).  I know it thinks point is at toplevel
> because that's what "C-c C-s" tells me.

> The "Heisenbug" part comes into play when I try to figure out which
> part of the buffer causes the problem, by selectively deleting some of
> the parts around point: after a few deletions, restoring the deleted
> parts exactly as they were makes the problem go away.

Hopefully the problem is repeatble by reloading the buffer.

> This is in Emacs 24.0.94.  Is this a known problem, and if so, was it
> already fixed since 24.0.94 was released?  (Since I don't have a way
> of reproducing the problem, I cannot test this in the current trunk.)
> If not, I will file a bug report, and please give me instructions for
> digging into the problem next time it happens, preferably without
> modifying the buffer (which seems to make the problem hide).

I think I saw something like this some while ago.  The best way of
approaching this is edebugging through c-guess-basic-syntax, which is
something best done by me.  (It's 1466 lines long.)

I think it would be best to file a bug report for this.

Thanks!

> TIA

-- 
Alan Mackenzie (Nuremberg, Germany).