diff --git a/openbsc/tests/abis/Makefile.am b/openbsc/tests/abis/Makefile.am
index c2e38de..cbc3e07 100644
--- a/openbsc/tests/abis/Makefile.am
+++ b/openbsc/tests/abis/Makefile.am
@@ -1,17 +1,35 @@
-AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include
-AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOABIS_CFLAGS) \
-	$(LIBOSMOGSM_CFLAGS) $(COVERAGE_CFLAGS)
+AM_CPPFLAGS = \
+	$(all_includes) \
+	-I$(top_srcdir)/include \
+	$(NULL)
 
-EXTRA_DIST = abis_test.ok
+AM_CFLAGS = \
+	-Wall \
+	-ggdb3 \
+	$(LIBOSMOCORE_CFLAGS) \
+	$(LIBOSMOABIS_CFLAGS) \
+	$(LIBOSMOGSM_CFLAGS) \
+	$(COVERAGE_CFLAGS) \
+	$(NULL)
 
-noinst_PROGRAMS = abis_test
+EXTRA_DIST = \
+	abis_test.ok \
+	$(NULL)
 
-abis_test_SOURCES = abis_test.c
+noinst_PROGRAMS = \
+	abis_test \
+	$(NULL)
+
+abis_test_SOURCES = \
+	abis_test.c \
+	$(NULL)
 
 abis_test_LDADD = \
-		$(top_builddir)/src/libbsc/libbsc.a \
-		$(top_builddir)/src/libcommon/libcommon.a \
-		$(top_builddir)/src/libbsc/libbsc.a \
-		$(top_builddir)/src/libtrau/libtrau.a \
-		$(LIBOSMOCORE_LIBS) $(LIBOSMOABIS_LIBS) \
-		$(LIBOSMOGSM_LIBS)
+	$(top_builddir)/src/libbsc/libbsc.a \
+	$(top_builddir)/src/libcommon/libcommon.a \
+	$(top_builddir)/src/libbsc/libbsc.a \
+	$(top_builddir)/src/libtrau/libtrau.a \
+	$(LIBOSMOCORE_LIBS) \
+	$(LIBOSMOABIS_LIBS) \
+	$(LIBOSMOGSM_LIBS) \
+	$(NULL)