diff --git a/tests/Makefile.am b/tests/Makefile.am
index 05df6a0..4e36bc3 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -46,7 +46,7 @@ lib_test_LDADD = libtest.la $(COMMON_LDADD)
 TESTS += lib_test
 
 userdata_test_SOURCES = userdata_test.c
-userdata_test_CFLAGS = $(COMMON_CFLAGS)
+userdata_test_CFLAGS = $(COMMON_CFLAGS) $(AM_CFLAGS)
 userdata_test_LDADD = libtest.la $(COMMON_LDADD)
 TESTS += userdata_test