Segfault on startup since update to qt-6.11.2

[Polynomial-C]

⚠️ Before submitting, please verify the following: ⚠️

• This is a bug, not a question or a configuration issue.
• This issue is not already reported on Github (I have searched for it).
• Nextcloud Server and Desktop Client are up to date. See Server Maintenance and Release Schedule and Desktop Releases for supported versions.
• I agree to follow Nextcloud's Code of Conduct

Bug description

Hi,

I have searched for duplicate issues and I think I haven't found any other report about this but I'm not 100% sure not to be wrong on this. Now to the bug:

Ever since I updated to qt-6.11.2 on my Gentoo Linux box, I can no longer successfully start nextcloud. It simply crashes with a segfault:

> gdb nextcloud
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Reading symbols from nextcloud...
(gdb) run
Starting program: /usr/bin/nextcloud
[New LWP 5710]
[New LWP 5711]
[New LWP 5712]
[New LWP 5713]
[New LWP 5714]
[New LWP 5715]
[New LWP 5716]
[New LWP 5717]
[New LWP 5718]
[New LWP 5719]
[New LWP 5720]

Thread 1 "nextcloud" received signal SIGSEGV, Segmentation fault.
0x00005555557a14c0 in QArrayDataPointer<QVariant>::needsDetach (this=0x0) at /usr/include/qt6/QtCore/qarraydatapointer.h:355
355         bool needsDetach() const noexcept { return !d || d->needsDetach(); }
(gdb) bt full
#0  0x00005555557a14c0 in QArrayDataPointer<QVariant>::needsDetach (this=0x0) at /usr/include/qt6/QtCore/qarraydatapointer.h:355
No locals.
#1  0x000055555579f967 in QtPrivate::QMovableArrayOps<QVariant>::emplace<QVariant> (this=0x7fffffffc9e0, i=0) at /usr/include/qt6/QtCore/qarraydataops.h:772
        detach = 93
        tmp = {d = {static MaxInternalSize = 24, data = {data = "\000\000\000\000\000\000\000\000\240ԆVUU\000\000\340\374\000\350\377\177\000", shared = 0x0, _forAlignment = 0}, is_shared = 0, is_null = 0, packedType = 35184372085448}}
        growsAtBegin = 86
        pos = (QArrayData::GrowsAtBeginning | unknown: 0x5554)
#2  0x00007ffff6ccd89e in ?? ()
No symbol table info available.
#3  0x00007fffffffcb60 in ?? ()
No symbol table info available.
#4  0x0000000000000000 in ?? ()
No symbol table info available.
(gdb)

I hope I don't need to recompile qt with debug symbols in order to provide useful information.

Steps to reproduce

1. update to qt-6.11.2
2. run nextcloud desktop client
3. Observe segfault

Expected behavior

Running desktop client.

Which files are affected by this bug

/usr/include/qt6/QtCore/qarraydataops.h

Operating system

Linux

Which version of the operating system you are running.

Gentoo (rolling releases)

Installation method

Distro package manager (please test with the AppImage package ?)

Nextcloud Server version

32.0.14

Nextcloud Desktop Client version

34.0.3

Did this occur after an update or on a clean installation?

Minor version update (i.e. 33.0.0 → 33.0.1)

Are you using the Nextcloud Server Encryption module?

No

Are you using an external user-backend?

• Default internal user-backend
• LDAP or Active Directory
• SSO - SAML
• Other

Nextcloud Server logs

Additional info

No response