diff --git a/tests/suites/test_suite_constant_time.function b/tests/suites/test_suite_constant_time.function
index d8a1fccbe5..bdd27f53dd 100644
--- a/tests/suites/test_suite_constant_time.function
+++ b/tests/suites/test_suite_constant_time.function
@@ -77,13 +77,13 @@ void mbedtls_ct_bool_xxx(char *x_str, char *y_str)
     expected = x1 <= y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
     TEST_EQUAL(mbedtls_ct_bool_le(x, y), expected);
 
-    expected = mbedtls_ct_bool(x1) ^ mbedtls_ct_bool(y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
+    expected = (!!x1) ^ (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
     TEST_EQUAL(mbedtls_ct_bool_xor(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected);
 
-    expected = mbedtls_ct_bool(x1) & mbedtls_ct_bool(y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
+    expected = (!!x1) && (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
     TEST_EQUAL(mbedtls_ct_bool_and(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected);
 
-    expected = mbedtls_ct_bool(x1) | mbedtls_ct_bool(y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
+    expected = (!!x1) || (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE;
     TEST_EQUAL(mbedtls_ct_bool_or(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected);
 
     TEST_CF_PUBLIC(&x, sizeof(x));