Merge branch 'heed-warnings-so-they-dont-have-to' into 'main'

ci: Build with -Wnonnull

See merge request GNOME/glib!3058

.gitlab-ci.yml

@@ -80,7 +80,7 @@ fedora-x86_64:
   stage: build
   needs: []
   variables:
-    CFLAGS: "-coverage -ftest-coverage -fprofile-arcs"
+    CFLAGS: "-coverage -ftest-coverage -fprofile-arcs -Wnonnull"
   script:
     - meson ${MESON_COMMON_OPTIONS}
             --werror
@@ -128,6 +128,8 @@ debian-stable-x86_64:
   image: $DEBIAN_IMAGE
   stage: build
   needs: []
+  variables:
+    CFLAGS: "-Wnonnull"
   script:
     - meson ${MESON_COMMON_OPTIONS}
             --werror