This showed up under asan.
GTK_PRINTER_CUPS (printer)->supports_collate = info->supports_collate;
GTK_PRINTER_CUPS (printer)->supports_number_up = info->supports_number_up;
GTK_PRINTER_CUPS (printer)->number_of_covers = info->number_of_covers;
+ g_clear_pointer (&(GTK_PRINTER_CUPS (printer)->covers), g_strfreev);
GTK_PRINTER_CUPS (printer)->covers = g_strdupv (info->covers);
status_changed = gtk_printer_set_job_count (printer, info->job_count);
status_changed |= gtk_printer_set_location (printer, info->location);