Re: 2.15.12 regtest problems

[address@hidden]

On Sep 23, 2011, at 11:26 AM, David Kastrup wrote:

> "address@hidden" <address@hidden> writes:
> 
>> On Sep 23, 2011, at 10:16 AM, Keith OHara wrote:
>> 
>>> On Fri, 23 Sep 2011 01:03:33 -0700, address@hidden
>>> <address@hidden> wrote:
>>> 
>>>> 
>>>> Slur::outside_callback has changed, however (see
>>>> dd855b6da30a050359a94ac719e0fc37a2fca666).
>>>> 
>>>> Perhaps this fixes the problem?
>>>> 
>>> 
>>> Maybe.  You'll have to ask the author of dd855b if that might have
>>> affected problems
>>> associated with the "no solution found for Bezier intersection" message.
>>> 
>>> He or she might be able to explain the 'weirdness'.
>>> 
>> 
>> As said author, I'm positive that I created this patch to fix a report
>> from a user that a binary was emitting "no solution found for Bezier
>> intersection."  However, it was limited to a specific case
>> (StrokeFinger), and I'm not sure if this problem is also the cause of
>> the issues being kicked around in the present thread.  That being
>> said, I'll try in the next couple days to rewind before that commit,
>> compile, and see if I get programming_erros from bezier.cc.
> 
> Mike, this kind of description really gives me the shivers.  It sounds
> like papering over problems wherever they randomly get exposed, thus
> actually hiding bugs rather than fixing them.
> 

I don't think the problem was randomly exposed, nor do I think the current 
solution hides a bug.

From my initial e-mail regarding the patch that I ultimately applied to current 
master:

--snip--

The issue is that the offset callback is tacked onto outside-staff
objects before we know if the object falls within the span of the slur.
Thus, even though these objects are weeded out of slur scoring in
score_extra_ecompasses, the callback function doesn't know they've been
weeded out and a separate weeding out needs to happen.  This patch does
that.

--snip--

> It may be just your choice of words, but don't make it harder for others
> to track down bugs that you don't know the real cause or fix for.  We
> can't really hope to find anybody more skilled at finding a bug than you
> are skilled at hiding it.

The above text from my original e-mail is my assertion that:

(a) I think I know the real cause (meaning that the cause does not run deeper 
than the issue as reported in my e-mail);
and
(b) The proposed patch is my best stab at fixing it.

If anyone disagreed with (or still disagrees with) my logic, it is important 
that the issue be raised ASAP (during the patch review process if possible).

When I say "the problem is limited to a specific case," I mean that I am not 
sure if these two bugs (fingerings being gobbled up and the StrokeFinger issue) 
are related, not that my patch seeks to address a specific symptom of a bug 
without eliminating the cause.

Cheers,
MS