Fix test under memsan

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/tests/suites/test_suite_constant_time.function b/tests/suites/test_suite_constant_time.function
index c61fb21..5dbba06 100644
--- a/tests/suites/test_suite_constant_time.function
+++ b/tests/suites/test_suite_constant_time.function
@@ -185,6 +185,7 @@
     int result = mbedtls_ct_memcmp(a, b, size);
     TEST_CF_PUBLIC(a, size);
     TEST_CF_PUBLIC(b, size);
+    TEST_CF_PUBLIC(&result, sizeof(result));
 
     TEST_EQUAL(result, 0);
 
@@ -199,6 +200,7 @@
             result = mbedtls_ct_memcmp(a, b, size);
             TEST_CF_PUBLIC(a, size);
             TEST_CF_PUBLIC(b, size);
+            TEST_CF_PUBLIC(&result, sizeof(result));
 
             TEST_ASSERT(result != 0);