--- /dev/null
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#include "IntStream.h"
+
+using namespace antlr4;
+
+const std::string IntStream::UNKNOWN_SOURCE_NAME = "<unknown>";
+
+IntStream::~IntStream() = default;