diff --git a/lib/c_glib/Makefile.am b/lib/c_glib/Makefile.am
old mode 100644
new mode 100755
index f72ff96..3244f74
--- a/lib/c_glib/Makefile.am
+++ b/lib/c_glib/Makefile.am
@@ -16,7 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-
+.NOTPARALLEL:
 SUBDIRS = . test
 
 pkgconfigdir = $(libdir)/pkgconfig
diff --git a/lib/c_glib/test/Makefile.am b/lib/c_glib/test/Makefile.am
old mode 100644
new mode 100755
index 7f2f3e3..7fed8e8
--- a/lib/c_glib/test/Makefile.am
+++ b/lib/c_glib/test/Makefile.am
@@ -16,7 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-
+.NOTPARALLEL:
 SUBDIRS =
 
 AM_CPPFLAGS = -g -Wall -I../src $(GLIB_CFLAGS)
diff --git a/lib/cpp/test/Makefile.am b/lib/cpp/test/Makefile.am
index 05ee9cc..d04cfb5 100755
--- a/lib/cpp/test/Makefile.am
+++ b/lib/cpp/test/Makefile.am
@@ -16,7 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-
+.NOTPARALLEL:
 noinst_LTLIBRARIES = libtestgencpp.la libprocessortest.la
 nodist_libtestgencpp_la_SOURCES = \
 	gen-cpp/DebugProtoTest_types.cpp \
diff --git a/lib/py/Makefile.am b/lib/py/Makefile.am
old mode 100644
new mode 100755
index 4a1df57..e33bf13
--- a/lib/py/Makefile.am
+++ b/lib/py/Makefile.am
@@ -16,7 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-
+.NOTPARALLEL:
 DESTDIR ?= /
 EXTRA_DIST = setup.py setup.cfg src compat