diff --git a/opal/mca/btl/usnic/Makefile.am b/opal/mca/btl/usnic/Makefile.am
index 9a270c043b0..17d62cc429e 100644
--- a/opal/mca/btl/usnic/Makefile.am
+++ b/opal/mca/btl/usnic/Makefile.am
@@ -16,6 +16,8 @@
 # Copyright (c) 2016-2017 IBM Corporation.  All rights reserved.
 # Copyright (c) 2017      Los Alamos National Security, LLC.  All rights
 #                         reserved.
+# Copyright (c) 2019      Research Organization for Information Science
+#                         and Technology (RIST).  All rights reserved.
 # $COPYRIGHT$
 #
 # Additional copyrights may follow
@@ -102,7 +104,7 @@ libmca_btl_usnic_la_LDFLAGS = \
 libmca_btl_usnic_la_LIBADD = $(opal_ofi_LIBS)
 
 if OPAL_BTL_USNIC_BUILD_UNIT_TESTS
-usnic_btl_run_tests_CPPFLAGS = \
+usnic_btl_run_tests_CPPFLAGS = $(AM_CPPFLAGS) \
     -DBTL_USNIC_RUN_TESTS_SYMBOL=\"opal_btl_usnic_run_tests\"
 usnic_btl_run_tests_SOURCES = test/usnic_btl_run_tests.c
 usnic_btl_run_tests_LDADD = -ldl