diff --git a/src/microhttpd/test_upgrade.c b/src/microhttpd/test_upgrade.c
index 950a5fb4..06e66a3c 100644
--- a/src/microhttpd/test_upgrade.c
+++ b/src/microhttpd/test_upgrade.c
@@ -526,7 +526,7 @@ notify_connection_cb (void *cls,
                       void **socket_context,
                       enum MHD_ConnectionNotificationCode toe)
 {
-  static int started;
+  static int started = MHD_NO;
 
   (void) cls;
   (void) connection;  /* Unused. Silent compiler warning. */
diff --git a/src/microhttpd/test_upgrade_large.c b/src/microhttpd/test_upgrade_large.c
index c321080e..817408fb 100644
--- a/src/microhttpd/test_upgrade_large.c
+++ b/src/microhttpd/test_upgrade_large.c
@@ -700,7 +700,7 @@ notify_connection_cb (void *cls,
                       void **socket_context,
                       enum MHD_ConnectionNotificationCode toe)
 {
-  static int started;
+  static int started = MHD_NO;
 
   (void) cls;
   (void) connection;  /* Unused. Silent compiler warning. */