Re: tracking down a crash

[David Kastrup]

"Keith E OHara" <address@hidden> writes:

> On Wed, 20 Nov 2013 23:48:47 -0800, David Kastrup <address@hidden> wrote:
>
>> So one suspicion would be that iter_ points to a non-operative
>> iterator.  Maybe set it to zero in
>
>> Sequential_iterator::do_quit ()
>
> That change, on master, did not clear the crash.
>
> release/2.18 gives good output on
> <http://www.mutopiaproject.org/cgibin/piece-info.cgi?id=1793>
>
> The first commit at which I see the crash (backtrace as posted earlier)  is 
> 3dc88bc7
> Issue 3648/1: Isolated durations in music sequences now stand for
> unpitched notes

Unlikely to be related other than by coincidence (memory layout,
whatever).  It's a small syntactic change that should only get its code
triggered by _use_ of the new syntax.

> Before that commit, I see 37 extra bar-lines in measure 60, after the
> first 8th note in a 2/4 measure, and following bar numbers are large
> by 36.

> The first commit at which I see the extra empty bars is f372c695
> Issue 3648/1: Isolated durations in music sequences now stand for unpitched 
> notes

No:

commit f372c695a52cf83ea00ff3be40acc542b4d46cbd
Author: David Kastrup <address@hidden>
Date:   Sun Nov 3 15:01:10 2013 +0100

    Issue 355: \repeat bar lines get messed up
    
    % the second repeat should start at the beginning of a bar, not
    % continue from the incomplete bar in the first ending.
    
    \version "2.17.30"
    \new Staff \relative {
      \partial 4
      \repeat volta 4 { e' | c2 d2 | e2 f2 | }
      \alternative { { g4 g g } { a a a a } }
      a b2.
    }

That sounds like a more likely contender.  Probably a missing context
property declaration or other protection?

> In any case, if I compile separately, rather than lilypond *.ly, I see
> no problem.

Missing context property declarations can lead to symbols getting
garbage-collected and reassigned between passes.

> Minimizing the example will take time, on Linux, so will be quite a
> lot of calendar time. Since release/2.18 works, I am not in a big
> hurry.

Need to get up now.  Later

-- 
David Kastrup