diff --git a/mk/spdk.mock.unittest.mk b/mk/spdk.mock.unittest.mk
index 8f4364da4..9599b67d3 100644
--- a/mk/spdk.mock.unittest.mk
+++ b/mk/spdk.mock.unittest.mk
@@ -30,7 +30,7 @@
 #  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
-SPDK_MOCK_SYSCALLS = \
+SPDK_MOCK_SYSCALLS += \
 	calloc \
 	pthread_mutexattr_init \
 	pthread_mutex_init \
diff --git a/test/unit/lib/rpc/rpc.c/Makefile b/test/unit/lib/rpc/rpc.c/Makefile
index bbf86539a..271d73ff7 100644
--- a/test/unit/lib/rpc/rpc.c/Makefile
+++ b/test/unit/lib/rpc/rpc.c/Makefile
@@ -35,6 +35,11 @@ SPDK_ROOT_DIR := $(abspath $(CURDIR)/../../../../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
 TEST_FILE = rpc_ut.c
-LDFLAGS +=-Wl,--wrap,open -Wl,--wrap,close -Wl,--wrap,unlink -Wl,--wrap,flock
+
+SPDK_MOCK_SYSCALLS = \
+	open \
+	close \
+	flock \
+	unlink
 
 include $(SPDK_ROOT_DIR)/mk/spdk.unittest.mk