[gtkmm/kjellahl/testci] CI: Test building gtk4, take 1

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 71d938b8d638be2fd89679a5f927f0c77276082b
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Feb 9 15:44:18 2022 +0100

    CI: Test building gtk4, take 1

 .gitlab-ci.yml | 41 +++++++----------------------------------
 1 file changed, 7 insertions(+), 34 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index b362a209..05266264 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -24,6 +24,12 @@ variables:
                   meson
                   ninja-build
                   glib-networking
+
+  # If libgtk-4-dev is too old, gtk4 is built as a subproject to gtkmm-4.0.
+  GTK4_BUILD_DEPS: libgstreamer1.0-dev
+                   libgstreamer-plugins-base1.0-dev
+                   libgstreamer-plugins-good1.0-dev
+                   libgstreamer-plugins-bad1.0-dev
   GIO_EXTRA_MODULES: "/usr/lib/x86_64-linux-gnu/gio/modules"
   GIT_SUBMODULE_STRATEGY: normal
 
@@ -106,7 +112,7 @@ release_gcc_build:
   extends: .build_default
   stage: build
   variables:
-    DEPENDENCIES: $MESON_GCC_DEPS
+    DEPENDENCIES: $MESON_GCC_DEPS $GTK4_BUILD_DEPS
   script:
     - ninja -C libsigc/_build install
     - ninja -C glibmm/_build install
@@ -137,39 +143,6 @@ release_gcc_build:
       - _build/meson-logs/testlog.txt
       - _build/meson-logs/meson-log.txt
 
-release_clang_build:
-  extends: .build_default
-  stage: build
-  variables:
-    DEPENDENCIES: $MESON_GCC_DEPS clang
-  script:
-    - ninja -C libsigc/_build install
-    - ninja -C glibmm/_build install
-    - ninja -C cairomm/_build install
-    - ninja -C pangomm/_build install
-    - mkdir _build && cd _build
-    # -Ddebug=false + -Doptimization=3 correspond to -Dbuildtype=release
-    - CC=clang CXX=clang++ meson --prefix=/usr --libdir=lib -Ddebug=false -Doptimization=3 -Dwarnings=fatal
-    - meson compile
-    # See comment in the release_gcc_build job.
-    # - meson test
-    - meson install
-  allow_failure: true
-  cache:
-    key: build-deps
-    paths:
-      - libsigc/
-      - glibmm/
-      - cairomm/
-      - pangomm/
-    policy: pull
-  artifacts:
-    when: on_failure
-    paths:
-      - _build/meson-logs/testlog.txt
-      - _build/meson-logs/meson-log.txt
-    expire_in: 1 week
-
 # Publish reference documentation at gnome.pages.gitlab.gnome.org/gtkmm
 pages:
   stage: deploy