diff --git a/tests/gsup/Makefile.am b/tests/gsup/Makefile.am
index 9a10597..04bc51a 100644
--- a/tests/gsup/Makefile.am
+++ b/tests/gsup/Makefile.am
@@ -1,9 +1,9 @@
 AM_CPPFLAGS = \
 	$(all_includes) \
+	-I$(top_srcdir)/include \
 	$(NULL)
 
 AM_CFLAGS = \
-	-I$(top_srcdir)/include \
 	$(LIBOSMOCORE_CFLAGS) \
 	$(LIBOSMOGSM_CFLAGS) \
 	$(NULL)