diff --git a/src/tests/Makefile.am b/src/tests/Makefile.am
index 5b51262..e2bea07 100644
--- a/src/tests/Makefile.am
+++ b/src/tests/Makefile.am
@@ -9,13 +9,13 @@
 
 noinst_HEADERS = test_common.h hnb-test.h hnb-test-layers.h
 
-HNBAP_FILES = $(top_srcdir)/src/hnbap_common.c $(top_srcdir)/src/hnbap_decoder.c $(top_srcdir)/src/hnbap_encoder.c
-RUA_FILES = $(top_srcdir)/src/rua_common.c $(top_srcdir)/src/rua_decoder.c $(top_srcdir)/src/rua_encoder.c $(top_srcdir)/src/rua_msg_factory.c
+HNBAP_FILES = $(top_srcdir)/src/hnbap_common.c $(top_builddir)/src/hnbap_decoder.c $(top_builddir)/src/hnbap_encoder.c
+RUA_FILES = $(top_srcdir)/src/rua_common.c $(top_builddir)/src/rua_decoder.c $(top_builddir)/src/rua_encoder.c $(top_srcdir)/src/rua_msg_factory.c
 
 test_helpers_SOURCES = test-helpers.c test_common.c
 test_helpers_LDADD = $(COMMON_LIBS) $(top_builddir)/src/libosmo-ranap.la
 
-test_hnbap_SOURCES = $(top_srcdir)/src/hnbap_common.c $(top_srcdir)/src/hnbap_decoder.c test-hnbap.c test_common.c
+test_hnbap_SOURCES = $(top_srcdir)/src/hnbap_common.c $(top_builddir)/src/hnbap_decoder.c test-hnbap.c test_common.c
 test_hnbap_LDADD = $(COMMON_LIBS) $(top_builddir)/src/hnbap/libosmo-asn1-hnbap.a $(top_builddir)/src/libosmo-ranap.la
 
 hnb_test_SOURCES = $(HNBAP_FILES) $(RUA_FILES) hnb-test.c test_common.c hnb-test-ranap.c hnb-test-rua.c