diff --git a/src/option_processing.cc b/src/option_processing.cc
index 9db33687..0f227d1c 100644
--- a/src/option_processing.cc
+++ b/src/option_processing.cc
@@ -186,11 +186,15 @@ error_code::Value option_processing(Option& op, bool standalone,
     bool noConf = false;
     std::string ucfname;
     std::stringstream cmdstream;
-    oparser->parseArg(cmdstream, uris, argc, argv);
     {
       // first evaluate --no-conf and --conf-path options.
       Option op;
-      oparser->parse(op, cmdstream);
+      if(argc == 0) {
+        oparser->parse(op, options);
+      } else {
+        oparser->parseArg(cmdstream, uris, argc, argv);
+        oparser->parse(op, cmdstream);
+      }
       noConf = op.getAsBool(PREF_NO_CONF);
       ucfname = op.get(PREF_CONF_PATH);
       if(standalone) {
diff --git a/test/Aria2ApiTest.cc b/test/Aria2ApiTest.cc
index fecf0f52..1f53bde3 100644
--- a/test/Aria2ApiTest.cc
+++ b/test/Aria2ApiTest.cc
@@ -32,7 +32,7 @@ public:
   void setUp()
   {
     SessionConfig config;
-    KeyVals options;
+    KeyVals options = {{"no-conf", "true"}};
     session_ = sessionNew(options, config);
   }