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+/* Template for deferring object creation until the object is needed.
+   Copyright (C) 2024-2025 Free Software Foundation, Inc.
+   Contributed by David Malcolm <dmalcolm@redhat.com>
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_LAZILY_CREATED_H
+#define GCC_LAZILY_CREATED_H
+
+/* A template for deferring object creation for a type T until the object
+   is needed, to avoid potentially expensive creation of T unless it's
+   actually needed (e.g. for directed graphs associated with a diagnostic,
+   which are ignored by the default "text" sink).  */
+
+template <typename T>
+class lazily_created
+{
+ public:
+  virtual ~lazily_created () {}
+
+  const T &
+  get_or_create () const
+  {
+    if (!m_object)
+      m_object = create_object ();
+    gcc_assert (m_object);
+    return *m_object;
+  }
+
+private:
+  virtual std::unique_ptr<T>
+  create_object () const = 0;
+
+  mutable std::unique_ptr<T> m_object;
+};
+
+#endif /* ! GCC_LAZILY_CREATED_H */