Segmentation fault on adding lyrics

Confirmed under Win 8.1 64-bit, same custom build. Factory reset made no difference.

Not just lyrics - also staff text, rehearsal marks, and presumably other types of text. Debugger shows abort() is being called, but I can't see a call stack. If I had to guess, I'd start by assuming this is related to the recent in text handling (replacing FreeSerifMScore with FreeSerif & using Bravura as a fallback font for music symbols). And I might further guess this is work in progress and will fix itself soon...

Tried setting breakpoints and single stepping where I could, but it seems the attempt to add the text is succeeding as far through the code as the debugger lets me step, and the abort happens after control returns to the Qt event loop (?). Which makes we wonder if the change is related to the change to Qt 5.2 on Windows. Except that I am thinking turtlevt is on Linux.

That wouldn't make the issue less critical, would it?

No. I didn't downgrade it on purpose. I think maybe I started the reply before it got upgrade - I had it pending a while as I tried debugging.

I suspected that :-)

Can't be related to the recent change to Qt 5.2.0 for Windows, as it happens on dfabf91 too, and that still uses Qt 5.1.1 (and no newer nightly build is available, strangely)

Does https://github.com/musescore/MuseScore/pull/666 fix it?

No, unfortunately it does not fix the crash when entering lyrics, I've just tried.
It doesn't fix the crash with systems and staff text either

Trying to add a staff text or lyrics ends with
...
Debug: select element type 0(state 0) staff 1
Debug: MuseScore::cmd
Debug: ===startCmd()
Debug: UndoStack::beginMacro 0x22a0f4b0, UndoStack 0x218b43c0
Debug: ScoreView::cmd
Debug: select element type 0(state 1) staff 1
Debug: UndoStack::endMacro 0
Debug: 0x22c42d40 exitState
Debug: ===startCmd()
Debug: UndoStack::beginMacro 0x22f54058, UndoStack 0x218b43c0
Fatal: ASSERT: "!isEmpty()" in file C:/Qt/5.2.0/mingw48_32/include/QtCore/qlist.h, line 288
So it looks like that PR might be the right way to fix it, but is at the wrong spot?

Haven't yet got it to show me a full stack trace

The stack trace should be this one:
Breakpoint 2, QList<Ms::TFragment>::first (this=0x24614550) at C:/Qt/5.2.0/mingw48_32/include/QtCore/qlist.h:288
288 inline const T& first() const { Q_ASSERT(!isEmpty()); return at(0); }
(gdb) bt
#0 QList<Ms::TFragment>::first (this=0x24614550) at C:/Qt/5.2.0/mingw48_32/include/QtCore/qlist.h:288
#1 0x00a89d03 in QList<Ms::TFragment>::front (this=0x24614550) at C:/Qt/5.2.0/mingw48_32/include/QtCore/qlist.h:304
#2 0x00a79e57 in Ms::TLine::y (this=0x24614550) at C:/Git_packages/MuseScore/libmscore/simpletext.h:103
#3 0x0076fbae in Ms::SimpleText::cursorRect (this=0x23fb70e8)
at C:\Git_packages\MuseScore\libmscore\simpletext.cpp:564
#4 0x00770a04 in Ms::SimpleText::layout (this=0x23fb70e8) at C:\Git_packages\MuseScore\libmscore\simpletext.cpp:706
#5 0x00679614 in Ms::Text::layout1 (this=0x23fb70e8) at C:\Git_packages\MuseScore\libmscore\text.cpp:230
#6 0x00711ac4 in Ms::Lyrics::layout (this=0x23fb70e8) at C:\Git_packages\MuseScore\libmscore\lyrics.cpp:195
#7 0x00771059 in Ms::SimpleText::startEdit (this=0x23fb70e8, pt=...)
at C:\Git_packages\MuseScore\libmscore\simpletext.cpp:772
#8 0x0067c8e1 in Ms::Text::startEdit (this=0x23fb70e8, view=0x23aa4198, p=...)
at C:\Git_packages\MuseScore\libmscore\text.cpp:614
#9 0x0057ca47 in Ms::ScoreView::startEdit (this=0x23aa4180) at C:\Git_packages\MuseScore\mscore\editelement.cpp:71
#10 0x00401842 in Ms::ScoreView::qt_static_metacall (_o=0x23aa4180, _c=QMetaObject::InvokeMetaMethod, _id=13,
_a=0x28cebc) at C:\Git_packages\MuseScore\build.debug\mscore\moc_scoreview.cpp:189
#11 0x68a167bb in ZN11QMetaObject8activateEP7QObjectiiPPv ()
from C:\Git_packages\MuseScore\win32install\bin\Qt5Core.dll
#12 0x00000001 in ?? ()
#13 0x00000018 in ?? ()
#14 0x23dda188 in ?? ()
#15 0x68c90da0 in ZN24QAbstractDeclarativeData9destroyedE ()

In particular, the crash seems to be happening at line 564 of libmscore\simpletext.cpp.

Ciao,
ABL

Or at line 103 of libmscore/simpletext.h

Changing line 564 of libmscore\simpletext.cpp back to
qreal y = _cursor.line * h;
like it was before 95bf389ff, in addition to the change from PR #666 seems to fix the crash

Actually it seems to be 2 independent crashes, the 1st when the cursor gets created, the 2md when the first character gets entered.

https://github.com/musescore/MuseScore/pull/668

No idea whether this is the right way, but it works for me.

Maurizio came up with an IMHO better fix in his https://github.com/musescore/MuseScore/pull/666 so I closed mine

Fixed in 98df31714e

Automatically closed -- issue fixed for 2 weeks with no activity.