diff --git a/openbsc/tests/channel/Makefile.am b/openbsc/tests/channel/Makefile.am
index 51b2f83..5654572 100644
--- a/openbsc/tests/channel/Makefile.am
+++ b/openbsc/tests/channel/Makefile.am
@@ -1,14 +1,34 @@
-AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include
-AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOABIS_CFLAGS)
+AM_CPPFLAGS = \
+	$(all_includes) \
+	-I$(top_srcdir)/include \
+	$(NULL)
 
-EXTRA_DIST = channel_test.ok
+AM_CFLAGS = \
+	-Wall \
+	-ggdb3 \
+	$(LIBOSMOCORE_CFLAGS) \
+	$(LIBOSMOGSM_CFLAGS) \
+	$(LIBOSMOABIS_CFLAGS) \
+	$(NULL)
 
-noinst_PROGRAMS = channel_test
+EXTRA_DIST = \
+	channel_test.ok \
+	$(NULL)
 
-channel_test_SOURCES = channel_test.c
+noinst_PROGRAMS = \
+	channel_test \
+	$(NULL)
+
+channel_test_SOURCES = \
+	channel_test.c \
+	$(NULL)
+
 channel_test_LDADD = \
 	$(top_builddir)/src/libbsc/libbsc.a \
 	$(top_builddir)/src/libmsc/libmsc.a \
 	$(top_builddir)/src/libcommon/libcommon.a \
 	$(LIBOSMOCORE_LIBS) \
-	-ldbi $(LIBOSMOGSM_LIBS) $(LIBCRYPTO_LIBS)
+	$(LIBOSMOGSM_LIBS) \
+	$(LIBCRYPTO_LIBS) \
+	-ldbi \
+	$(NULL)