diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index d1fc2582d..d4e8ac808 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -301,7 +301,7 @@ uint64_t parse_binary_string(data_t *bin_string)
     uint64_t result = 0;
     TEST_LE_U(bin_string->len, 8);
     for (size_t i = 0; i < bin_string->len; i++) {
-        result |= ((bin_string->x)[i]) << (i * 8);
+        result = (uint64_t) result | bin_string->x[i];
     }
 exit:
     return result; /* returns 0 if len > 8 */