Crash of MuseScore 3 on opening a certain 2.x score

• Jan 3, 2019 - 11:48
Reported version
P1 - High
S1 - Blocker

I just tried to open a Musescore 2 file of this:
But Musescore 3 always refuses to open it. When I open it again, Musescore quits after asking yes or no of an unnormally opened file. What's wrong?



Regression No Yes
Workaround No Yes
Priority P1 - High

That score got created (or rather last saved) with MuseScore 2.0.3. Attached here in case it gets removed or changed on

Exporting as musicxml in 2.3.2 (attached) and importing that in 3.0 works (after ignoring a MusicXML error reg. some figured bass element, guess we need a separate issue for this), so this might serve as a workaround (as does opening it with 2.x).

Latest master build crahes on it too. 'fammous last words':
Fatal: ASSERT: "!isEmpty()" in file C:/Qt/5.12.0/mingw73_64/include/QtCore/qvector.h, line 237 (C:/Qt/5.12.0/mingw73_64/include/QtCore/qvector.h:237, )

The easiest way to prevent this crash is to add these lines at the beginning of Beam::addSkyline()

      if (beamSegments.empty())

I don't know why a beam's beamSegments list would be empty, but I feel good about this solution because these two lines appear at the beginning of Beam::draw(), and they were added by Werner on 25 October 2016.

In reply to by Git Message

This sounds suspiciously like a problem I had shortly after the alpha was released. @mattmcclinch, I thought you said you ran across the same issue when I was making some beams horizontal. You fixed it so the score would open, but I can't find the issue right now.

Also, I discovered that Musescore 3 files have no bar numbers when stating measures, while 2 have. This Stravinsky work has two bar number changes so that every piece starts from bar 1. But Musicxml exports all bars continuously, without any resets. So should I open another issue to say this?


Haipeng, I don't see how this relates to the issue in this subject. Start a thread in the General discussion forum.

@matt, I remember a file I couldn't open, and I thought it was you that fixed it, but it might have been someone else and there may not have been an issue but rather only a forum post.

Ok, I'll try to describe the measure numbers in general discuss. Now I'm a bit afraid to use Musescore directly to convert into Musicxml, for I just found there are lots of texts missing when exporting. E.g., there are texts attached to hairpins, the "simile" at the 3rd bar of movement 2 and the cresc. near the beginning of movement 3. I need to create text tags out of the hairpins to use them. Perhaps this can be an issue.


a prime example of what happens when a forum post about a genuine bug gets forgotten to get entered into the issue tracker :-/
Had it been, this issue would probably been fixed before any Beta release...

Not accusing anyone, just noting and putting emphasis on the importance of the issue tracker

Fix version