FTBFS with Vala 0.56.16

[bobby285271]

Prerequisites

• I have searched open and closed issues for duplicates.

Describe the bug

Vala 0.56.16, GLib 2.80.0:

FAILED: io.elementary.notifications.p/src/AbstractBubble.c io.elementary.notifications.p/src/Application.c io.elementary.notifications.p/src/Bubble.c io.elementary.notifications.p/src/Confirmation.c io.elementary.notifications.p/src/DBus.c io.elementary.notifications.p/src/FdoActionGroup.c io.elementary.notifications.p/src/Notification.c io.elementary.notifications.p/src/Widgets/MaskedImage.c 
valac -C --vapidir /build/source/vapi --pkg libhandy-1 --pkg gtk+-3.0 --pkg granite --pkg gio-2.0 --pkg gobject-2.0 --pkg glib-2.0 --pkg libcanberra-gtk3 --pkg libcanberra --color=always --directory io.elementary.notifications.p --basedir ../ --gresources=../data/notifications.gresource.xml ../src/AbstractBubble.vala ../src/Application.vala ../src/Bubble.vala ../src/Confirmation.vala ../src/DBus.vala ../src/FdoActionGroup.vala ../src/Notification.vala ../src/Widgets/MaskedImage.vala
../src/FdoActionGroup.vala:62.5-62.37: error: overriding method `Notifications.Fdo.ActionGroup.query_action' is incompatible with base method `bool GLib.ActionGroup.query_action (string, out bool, out weak GLib.VariantType, out weak GLib.VariantType, out GLib.Variant, out GLib.Variant)': incompatible type of parameter 3.
   62 |     public override bool query_action (
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
Compilation failed: 1 error(s), 0 warning(s)
[6/18] Compiling Vala source ../demo/Application.vala ../demo/MainWindow.vala
ninja: build stopped: subcommand failed.

Full build log

building '/nix/store/fpq5jfbh4w81flwj0m7dpribxaj7fnrb-elementary-notifications-7.0.1.drv'...
Running phase: unpackPhase
unpacking source archive /nix/store/p4awzw8gypli49mqc0v51xy1mkrdwc7r-source
source root is source
Running phase: patchPhase
Running phase: updateAutotoolsGnuConfigScriptsPhase
Running phase: configurePhase
mesonConfigurePhase flags: --prefix=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1 --libdir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/lib --libexecdir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/libexec --bindir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/bin --sbindir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/sbin --includedir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/include --mandir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/man --infodir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/info --localedir=/nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/locale -Dauto_features=enabled -Dwrap_mode=nodownload --buildtype=plain
The Meson build system
Version: 1.3.2
Source dir: /build/source
Build dir: /build/source/build
Build type: native build
Project name: io.elementary.notifications
Project version: 7.0.1
C compiler for the host machine: gcc (gcc 13.2.0 "gcc (GCC) 13.2.0")
C linker for the host machine: gcc ld.bfd 2.41
Vala compiler for the host machine: valac (valac 0.56.16)
Host machine cpu family: x86_64
Host machine cpu: x86_64
Found pkg-config: YES (/nix/store/a3752l19hc76dmzh1wgrxbsxh6lfx67z-pkg-config-wrapper-0.29.2/bin/pkg-config) 0.29.2
Build-time dependency gio-2.0 found: YES 2.80.0
Program /nix/store/615hnkjcbk0b6yv3mxsbmzzh6c1gai3d-glib-2.80.0-dev/bin/glib-compile-resources found: YES (/nix/store/615hnkjcbk0b6yv3mxsbmzzh6c1gai3d-glib-2.80.0-dev/bin/glib-compile-resources)
Run-time dependency libcanberra found: YES 0.30
Run-time dependency libcanberra-gtk3 found: YES 0.30
Run-time dependency glib-2.0 found: YES 2.80.0
Run-time dependency gobject-2.0 found: YES 2.80.0
Dependency gio-2.0 found: YES 2.80.0 (cached)
Run-time dependency granite found: YES 6.2.0
Run-time dependency gtk+-3.0 found: YES 3.24.41
Run-time dependency libhandy-1 found: YES 1.8.3
Program msgfmt found: YES (/nix/store/c34vc40ksciy7y2w1d410gwragbx8sch-gettext-0.21.1/bin/msgfmt)
Dependency granite found: YES 6.2.0 (cached)
Dependency gtk+-3.0 found: YES 3.24.41 (cached)
po/extra/meson.build:2: WARNING: Project targets '>= 0.57' but uses feature deprecated since '0.56.0': meson.source_root. use meson.project_source_root() or meson.global_source_root() instead.
Program msginit found: YES (/nix/store/c34vc40ksciy7y2w1d410gwragbx8sch-gettext-0.21.1/bin/msginit)
Program msgmerge found: YES (/nix/store/c34vc40ksciy7y2w1d410gwragbx8sch-gettext-0.21.1/bin/msgmerge)
Program xgettext found: YES (/nix/store/c34vc40ksciy7y2w1d410gwragbx8sch-gettext-0.21.1/bin/xgettext)
Dependency gio-2.0 found: YES 2.80.0 (cached)
Program /nix/store/615hnkjcbk0b6yv3mxsbmzzh6c1gai3d-glib-2.80.0-dev/bin/glib-compile-schemas found: YES (/nix/store/615hnkjcbk0b6yv3mxsbmzzh6c1gai3d-glib-2.80.0-dev/bin/glib-compile-schemas)
Build targets in project: 208
WARNING: Deprecated features used:
 * 0.56.0: {'meson.source_root'}

io.elementary.notifications 7.0.1

  User defined options
    auto_features: enabled
    bindir       : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/bin
    buildtype    : plain
    includedir   : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/include
    infodir      : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/info
    libdir       : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/lib
    libexecdir   : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/libexec
    localedir    : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/locale
    mandir       : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/share/man
    prefix       : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1
    sbindir      : /nix/store/kw16g8rv4ggys0w37ml0j30igyld9arf-elementary-notifications-7.0.1/sbin
    wrap_mode    : nodownload

Found ninja-1.11.1 at /nix/store/d6bvhfhg3aw2lj0nyb08y0ahlj5md6p8-ninja-1.11.1/bin/ninja
mesonConfigurePhase: enabled\ parallel\ building
Running phase: buildPhase
build flags: -j12
[1/18] Generating css-resource_h with a custom command
[2/18] Generating css-resource_c with a custom command
[3/18] Merging translations for data/io.elementary.notifications.metainfo.xml
[4/18] Compiling C object io.elementary.notifications.p/meson-generated_.._css-resource.c.o
[5/18] Compiling Vala source ../src/AbstractBubble.vala ../src/Application.vala ../src/Bubble.vala ../src/Confirmation.vala ../src/DBus.vala ../src/FdoActionGroup.vala ../src/Notification.vala ../src/Widgets/MaskedImage.vala
FAILED: io.elementary.notifications.p/src/AbstractBubble.c io.elementary.notifications.p/src/Application.c io.elementary.notifications.p/src/Bubble.c io.elementary.notifications.p/src/Confirmation.c io.elementary.notifications.p/src/DBus.c io.elementary.notifications.p/src/FdoActionGroup.c io.elementary.notifications.p/src/Notification.c io.elementary.notifications.p/src/Widgets/MaskedImage.c 
valac -C --vapidir /build/source/vapi --pkg libhandy-1 --pkg gtk+-3.0 --pkg granite --pkg gio-2.0 --pkg gobject-2.0 --pkg glib-2.0 --pkg libcanberra-gtk3 --pkg libcanberra --color=always --directory io.elementary.notifications.p --basedir ../ --gresources=../data/notifications.gresource.xml ../src/AbstractBubble.vala ../src/Application.vala ../src/Bubble.vala ../src/Confirmation.vala ../src/DBus.vala ../src/FdoActionGroup.vala ../src/Notification.vala ../src/Widgets/MaskedImage.vala
../src/FdoActionGroup.vala:62.5-62.37: error: overriding method `Notifications.Fdo.ActionGroup.query_action' is incompatible with base method `bool GLib.ActionGroup.query_action (string, out bool, out weak GLib.VariantType, out weak GLib.VariantType, out GLib.Variant, out GLib.Variant)': incompatible type of parameter 3.
   62 |     public override bool query_action (
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
Compilation failed: 1 error(s), 0 warning(s)
[6/18] Compiling Vala source ../demo/Application.vala ../demo/MainWindow.vala
ninja: build stopped: subcommand failed.

We are able to workaround the issue by replacing out VariantType with out unowned VariantType, though it is always unclear to me whether this is actually an elementary issue 😂

notifications/src/FdoActionGroup.vala

Lines 65 to 66 in 9b07160

	out VariantType parameter_type,
	out VariantType state_type,

To Reproduce

Steps to reproduce the behavior:

1. Build with Vala 0.56.16

Expected behavior

Builds.

Platform Information

NixOS (using custom checkout).

• I'm using the latest version from git that I've manually compiled
• I'm using the latest released stable version