diff --git a/src/internal.c b/src/internal.c
index 0f9d093ab3..ac9502d145 100644
--- a/src/internal.c
+++ b/src/internal.c
@@ -25165,11 +25165,13 @@ const char* wolfSSL_ERR_reason_error_string(unsigned long e)
         return wc_GetErrorString(error);
     }
 
-#ifdef OPENSSL_EXTRA
     if (error == 0) {
+#ifdef OPENSSL_EXTRA
         return "ok";
-    }
+#else
+        goto unknown_error_number;
 #endif
+    }
 
     switch ((enum wolfSSL_ErrorCodes)error) {
 
@@ -25730,6 +25732,7 @@ const char* wolfSSL_ERR_reason_error_string(unsigned long e)
     }
 #endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL || HAVE_WEBSERVER || HAVE_MEMCACHED */
 
+unknown_error_number:
     return "unknown error number";
 
 #endif /* NO_ERROR_STRINGS */