diff --git a/extensions/GNUmakefile.in b/extensions/GNUmakefile.in
index 218dc3a..88ab31d 100644
--- a/extensions/GNUmakefile.in
+++ b/extensions/GNUmakefile.in
@@ -76,7 +76,7 @@ install: ${targets_install}
 	if test -n "${targets_install}"; then install -pm0755 $^ "${DESTDIR}${xtlibdir}/"; fi;
 
 clean:
-	rm -f *.o *.oo *.so *.a {matches,targets}[46].man initext.c initext4.c initext6.c;
+	rm -f *.o *.oo *.so *.a .*.d *.d {matches,targets}[46].man initext.c initext4.c initext6.c;
 
 distclean: clean
 	rm -f .*.d .*.dd;