Changing instruments from a tablature crashes the program
OS: Windows 10 (10.0), Arch.: x86_64, MuseScore version (64-bit): 3.4.2.9788, revision: 148e43f
I know that this is not supported, and that the opposite use case is probably more tempting (ex: wanting to get a guitar tablature from a piano score, it's not uncommon to read it on the forums).
Nevertheless, I suppose that this one, e.g. from a tablature retrieved somewhere, for wanting to obtain a violin score, is not completely to be ruled out.
With 2.3.2, it failed, of course, with this display of red squares and question marks - image below (and by undoing, the situation returned to the way it was before).
With 3.4.2, the program doesn't like it at all and dies immediately. That should not happen.
So, steps:
1) Open this test file: TAB.mscz
(excerpt of Tablature template with a few notes):
2) Right-click TAB staff-> Staff properties -> Change instrument -> Let say, violin (or flute, or piano) -> Ok
Result: the programm shuts down
-
result with the 2.3.2
Comments
I cannot reproduce the crash using the latest version on the master branch.
(OS: Ubuntu 18.04.3 LTS, Arch.: x86_64, MuseScore version (64-bit): 3.5.0, revision: 3543170)
Well, whether 3.4.2, 148e43f or last nightly 8641f28 crash in the same way (Windows10)
I cannot reproduce under Linux, but I can under Windows.
Under Linux, with AddressSanitizer and UndefinedBehaviorSanitizer, I see the runtime message:
libmscore/stringdata.cpp:154:26: runtime error: variable length array bound evaluates to non-positive value 0Under Windows, with AddressSanitizer (via Clang), the backtrace of the crash is the following:
==1928==ERROR: AddressSanitizer: access-violation on unknown address 0xffffffffffffffff (pc 0x000145094ddd bp 0x00000013d240 sp 0x00000013cf80 T0)==1928==The signal is caused by a READ memory access.
#0 0x145094ddc in Ms::StringData::fretChords(class Ms::Chord *)const C:\Git_packages\MuseScore\libmscore\stringdata.cpp:248
#1 0x142658851 in Ms::Chord::cmdUpdateNotes(class Ms::AccidentalState *) C:\Git_packages\MuseScore\libmscore\chord.cpp:1723
#2 0x142f0a84a in Ms::Score::getNextMeasure(struct Ms::LayoutContext &) C:\Git_packages\MuseScore\libmscore\layout.cpp:2654
#3 0x142f5cd78 in Ms::Score::doLayoutRange(class Ms::Fraction const &,class Ms::Fraction const &) C:\Git_packages\MuseScore\libmscore\layout.cpp:4496
#4 0x1419619ca in Ms::Score::update(bool) C:\Git_packages\MuseScore\libmscore\cmd.cpp:302
#5 0x14026b8ea in Ms::Score::update(void) C:\Git_packages\MuseScore\libmscore\score.h:737
#6 0x1438b8427 in Ms::EditStaff::apply(void) C:\Git_packages\MuseScore\mscore\editstaff.cpp:404
#7 0x1438b2c55 in Ms::EditStaff::bboxClicked(class QAbstractButton *) C:\Git_packages\MuseScore\mscore\editstaff.cpp:287
The
strings()function returns 0 after the instrument change, so I don't think the bUsed vector is properly created here:https://github.com/musescore/MuseScore/blob/9eec241511a84df61210d79efe4…
(even in Linux case, here: https://github.com/musescore/MuseScore/blob/9eec241511a84df61210d79efe4… )
So how about a few lines above to use
That might prevent the crash, but we can do better. The problem, of course, is that the user has selected an instrument that is incompatible with the staff type, but the staff type is not updated to be compatible with the instrument. StringData::fretChords() is only called if the staff type is part of the TAB staff group, so choosing an appropriate staff type will effectively solve this issue. And indeed, if the staff type is changed to "Standard" (via the instruments dialog) before choosing a different instrument in the Edit Staff dialog, the operation succeeds without a problem. See https://github.com/musescore/MuseScore/pull/5761 for my solution.
Fixed in branch master, commit f215d00c98
_fix #301488: Changing instruments from a tablature crashes the program
Resolves: https://musescore.org/en/node/301488.
When the user chooses a different instrument in the "Edit Staff" dialog box, it is important to make sure that the new instrument is not incompatible with the staff type. This is accomplished by setting the staff type to the preset staff type for the chosen instrument._
Fixed in branch master, commit 9f2a861d74
_Merge pull request #5761 from mattmcclinch/301488-edit-staff
fix #301488: Changing instruments from a tablature crashes the program_
Automatically closed -- issue fixed for 2 weeks with no activity.