diff --git a/gio/gdbusauthmechanismsha1.c b/gio/gdbusauthmechanismsha1.c
index 4d9438f6c..cadcc9982 100644
--- a/gio/gdbusauthmechanismsha1.c
+++ b/gio/gdbusauthmechanismsha1.c
@@ -1033,6 +1033,7 @@ mechanism_server_data_send (GDBusAuthMechanism   *mechanism,
   /* TODO: use GDBusAuthObserver here to get the cookie context to use? */
   cookie_context = "org_gtk_gdbus_general";
 
+  cookie_id = -1;
   error = NULL;
   if (!keyring_generate_entry (cookie_context,
                                &cookie_id,
diff --git a/gio/gdbusmessage.c b/gio/gdbusmessage.c
index d61a30ad7..d29edbe0f 100644
--- a/gio/gdbusmessage.c
+++ b/gio/gdbusmessage.c
@@ -2143,6 +2143,7 @@ g_dbus_message_to_blob (GDBusMessage          *message,
   mos = G_MEMORY_OUTPUT_STREAM (g_memory_output_stream_new (NULL, 0, g_realloc, g_free));
   dos = g_data_output_stream_new (G_OUTPUT_STREAM (mos));
 
+  byte_order = G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN;
   switch (message->byte_order)
     {
     case G_DBUS_MESSAGE_BYTE_ORDER_BIG_ENDIAN:
diff --git a/gio/gdbusproxy.c b/gio/gdbusproxy.c
index 9e42511a4..d096a5a63 100644
--- a/gio/gdbusproxy.c
+++ b/gio/gdbusproxy.c
@@ -2470,6 +2470,7 @@ g_dbus_proxy_call_sync (GDBusProxy      *proxy,
                                G_IO_ERROR,
                                G_IO_ERROR_FAILED,
                                _("Cannot invoke method; proxy is for a well-known name without an owner and proxy was constructed with the G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START flag"));
+          ret = NULL;
           goto out;
         }
     }
diff --git a/gio/gdbusserver.c b/gio/gdbusserver.c
index 8fd1291c4..d957d225b 100644
--- a/gio/gdbusserver.c
+++ b/gio/gdbusserver.c
@@ -1023,6 +1023,7 @@ initable_init (GInitable     *initable,
   GError *last_error;
 
   ret = FALSE;
+  addr_array = NULL;
   last_error = NULL;
 
   if (!g_dbus_is_guid (server->guid))
diff --git a/gio/tests/gdbus-introspection.c b/gio/tests/gdbus-introspection.c
index 740f7c1bf..d0f6c26e2 100644
--- a/gio/tests/gdbus-introspection.c
+++ b/gio/tests/gdbus-introspection.c
@@ -265,6 +265,8 @@ test_default_direction (void)
   g_dbus_node_info_unref (info);
 }
 
+#if 0
+/* XXX: need to figure out how generous we want to be here */
 /* test that extraneous attributes are ignored
  */
 static void
@@ -297,6 +299,7 @@ test_extra_data (void)
 
   g_dbus_node_info_unref (info);
 }
+#endif
 
 /* ---------------------------------------------------------------------------------------------------- */
 
@@ -320,7 +323,7 @@ main (int   argc,
   g_test_add_func ("/gdbus/introspection-generate", test_generate);
   g_test_add_func ("/gdbus/introspection-default-direction", test_default_direction);
 #if 0
-  /* need to figure out how generous we want to be here */
+  /* XXX: need to figure out how generous we want to be here */
   g_test_add_func ("/gdbus/introspection-extra-data", test_extra_data);
 #endif
 
diff --git a/gio/tests/gdbus-peer.c b/gio/tests/gdbus-peer.c
index 49ffa8b97..487b6d0ce 100644
--- a/gio/tests/gdbus-peer.c
+++ b/gio/tests/gdbus-peer.c
@@ -736,6 +736,7 @@ test_peer (void)
     g_object_unref (method_reply_message);
 
     error = NULL;
+    len = 0;
     buf = read_all_from_fd (fd, &len, &error);
     g_assert_no_error (error);
     g_assert (buf != NULL);