diff --git a/lib/cpp/test/Makefile.am b/lib/cpp/test/Makefile.am
index f15b0c1..4d61e37 100755
--- a/lib/cpp/test/Makefile.am
+++ b/lib/cpp/test/Makefile.am
@@ -16,7 +16,8 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-.NOTPARALLEL:
+AUTOMAKE_OPTIONS = subdir-objects serial-tests
+
 noinst_LTLIBRARIES = libtestgencpp.la libprocessortest.la
 nodist_libtestgencpp_la_SOURCES = \
 	gen-cpp/DebugProtoTest_types.cpp \