clean_display     424 contrib/libtests/pngunknown.c       clean_display(d);
clean_display     670 contrib/libtests/pngunknown.c       clean_display(d);
clean_display     785 contrib/libtests/pngunknown.c          clean_display(d);
clean_display     836 contrib/libtests/pngunknown.c    clean_display(d);