Bug#1144670: libgtk-4-1: all applications crash on startup when a wayland compositor supports dmabuf v6

[Gabri]

Package: libgtk-4-1
Version: 4.18.6+ds-2
Followup-For: Bug #1144670
X-Debbugs-Cc: 13gabriele32 at gmail.com

Dear Maintainer,
I can reproduce what appears to be the same issue on Debian 13 Trixie with the Niri Wayland compositor and libgtk-4-1 version 4.18.6+ds-2.

Both Loupe and Nautilus consistently crash with SIGSEGV during GTK4 Wayland display initialization.

I tested the following workarounds:

- GSK_RENDERER=gl: still crashes
- GSK_RENDERER=cairo: still crashes
- GTK_THEME=Adwaita: still crashes
- GDK_BACKEND=x11: both applications work correctly through XWayland
The Loupe coredump shows the following stack frames:

```
#0  libgtk-4.so.1 + 0x47d730
#4  libwayland-client.so.0
#6  wl_display_dispatch_queue_pending
#8  gdk_display_manager_open_display
#9  gtk_init_check
#10 gtk_init
```

This appears consistent with the Wayland dmabuf v6 issue described in this bug, although I have not independently verified the root cause.

I have not tested the GTK4 version from Debian Testing.


-- System Information:
Debian Release: 13.7
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 6.12.111+deb13-amd64 (SMP w/4 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_WARN, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=it_IT.UTF-8, LC_CTYPE=it_IT.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libgtk-4-1 depends on:
ii  adwaita-icon-theme            48.1-1
ii  hicolor-icon-theme            0.18-2
ii  libc6                         2.41-12+deb13u4
ii  libcairo-gobject2             1.18.4-1+b1
ii  libcairo-script-interpreter2  1.18.4-1+b1
ii  libcairo2                     1.18.4-1+b1
ii  libcloudproviders0            0.3.6-2
ii  libcolord2                    1.4.7-3
ii  libcups2t64                   2.4.10-3+deb13u2
ii  libepoxy0                     1.5.10-2
ii  libfontconfig1                2.15.0-2.3
ii  libfribidi0                   1.0.16-1
ii  libgdk-pixbuf-2.0-0           2.42.12+dfsg-4+deb13u1
ii  libgles2                      1.7.0-1+b2
ii  libglib2.0-0t64               2.84.4-3~deb13u5
ii  libgraphene-1.0-0             1.10.8-5
ii  libgtk-4-common               4.18.6+ds-2
ii  libharfbuzz-subset0           10.2.0-1+deb13u1
ii  libharfbuzz0b                 10.2.0-1+deb13u1
ii  libjpeg62-turbo               1:2.1.5-4
ii  libpango-1.0-0                1.56.3-1
ii  libpangocairo-1.0-0           1.56.3-1
ii  libpangoft2-1.0-0             1.56.3-1
ii  libpng16-16t64                1.6.48-1+deb13u6
ii  libtiff6                      4.7.0-3+deb13u3
ii  libvulkan1                    1.4.309.0-1
ii  libwayland-client0            1.23.1-3
ii  libwayland-egl1               1.23.1-3
ii  libx11-6                      2:1.8.12-1
ii  libxcursor1                   1:1.2.3-1
ii  libxdamage1                   1:1.1.6-1+b2
ii  libxext6                      2:1.3.4-1+b3
ii  libxfixes3                    1:6.0.0-2+b4
ii  libxi6                        2:1.8.2-1
ii  libxinerama1                  2:1.1.4-3+b4
ii  libxkbcommon0                 1.7.0-2
ii  libxrandr2                    2:1.5.4-1+b3
ii  shared-mime-info              2.4-5+b2

Versions of packages libgtk-4-1 recommends:
ii  iso-codes                 4.18.0-1
ii  libgtk-4-bin              4.18.6+ds-2
ii  libgtk-4-media-gstreamer  4.18.6+ds-2
ii  librsvg2-common           2.60.0+dfsg-1

Versions of packages libgtk-4-1 suggests:
ii  gvfs  1.57.2-2+deb13u1

Versions of packages libgtk-4-1 is related to:
ii  fcitx5-frontend-gtk4  5.1.3-3
ii  ibus-gtk4             1.5.32-2
pn  scim-gtk-immodule     <none>

-- no debconf information