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diff --git a/gcc/diagnostics/lazy-paths.h b/gcc/diagnostics/lazy-paths.h
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+/* Helper class for deferring path creation until a diagnostic is emitted.
+   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_DIAGNOSTICS_LAZY_PATHS_H
+#define GCC_DIAGNOSTICS_LAZY_PATHS_H
+
+#include "diagnostics/paths.h"
+
+namespace diagnostics {
+namespace paths {
+
+/* An implementation of diagnostics::paths::path which has a trivial ctor
+   and lazily creates another path the first time the path
+   is queried, deferring to this inner path for all queries.
+
+   Use this to avoid expensive path creation logic when creating
+   rich_location instances, so that expense can be deferred until the path
+   is actually used by a diagnostic, and thus avoided for warnings that
+   are disabled.  */
+
+class lazy_path : public path
+{
+ public:
+  virtual ~lazy_path () {}
+
+  unsigned num_events () const final override;
+  const event & get_event (int idx) const final override;
+  unsigned num_threads () const final override;
+  const thread &
+  get_thread (thread_id_t) const final override;
+  bool
+  same_function_p (int event_idx_a,
+		   int event_idx_b) const final override;
+
+  bool generated_p () const { return m_inner_path != nullptr; }
+
+protected:
+  lazy_path (const logical_locations::manager &logical_loc_mgr)
+  : path (logical_loc_mgr)
+  {
+  }
+
+ private:
+  void lazily_generate_path () const;
+  virtual std::unique_ptr<path> make_inner_path () const = 0;
+
+  mutable std::unique_ptr<path> m_inner_path;
+};
+
+} // namespace paths
+} // namespace diagnostics
+
+#endif /* ! GCC_DIAGNOSTICS_LAZY_PATHS_H */