diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f8d7f2417a..ddbee0dfc4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -405,7 +405,6 @@ asan-build:
   artifacts:
     paths:
       - _build/meson-logs
-  allow_failure: true
 
 reference:
   image: $FEDORA_IMAGE
diff --git a/gtk/gtklistitemmanager.c b/gtk/gtklistitemmanager.c
index 503149ea7c..b25cac7b06 100644
--- a/gtk/gtklistitemmanager.c
+++ b/gtk/gtklistitemmanager.c
@@ -1293,7 +1293,7 @@ gtk_list_item_manager_ensure_items (GtkListItemManager *self,
                                                              start,
                                                              GTK_LIST_TILE_UNMATCHED_FOOTER,
                                                              GTK_LIST_TILE_HEADER);
-              g_assert (header->widget == NULL);
+              g_assert (header != NULL && header->widget == NULL);
               header->widget = GTK_WIDGET (gtk_list_item_change_get_header (change));
               if (header->widget == NULL)
                 header->widget = GTK_WIDGET (self->create_header_widget (self->widget));