diff --git a/Makefile.pre.in b/Makefile.pre.in
index a85f8ddf1cb..9cc15c963e1 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -917,7 +917,8 @@ XMLLIBSUBDIRS=  xml xml/dom xml/etree xml/parsers xml/sax
 LIBSUBDIRS=	tkinter tkinter/test tkinter/test/test_tkinter \
 		tkinter/test/test_ttk site-packages test \
 		test/capath test/data \
-		test/cjkencodings test/decimaltestdata test/xmltestdata test/subprocessdata \
+		test/cjkencodings test/decimaltestdata test/xmltestdata \
+		test/subprocessdata test/sndhdrdata \
 		test/tracedmodules test/encoded_modules \
 		concurrent concurrent/futures encodings \
 		email email/mime email/test email/test/data \