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diff --git a/gcc/rust/expand/rust-derive-eq.h b/gcc/rust/expand/rust-derive-eq.h
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+// Copyright (C) 2025 Free Software Foundation, Inc.
+
+// 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 RUST_DERIVE_EQ_H
+#define RUST_DERIVE_EQ_H
+
+#include "rust-derive.h"
+
+namespace Rust {
+namespace AST {
+
+// FIXME: Need to figure out structuraleq marker trait
+
+class DeriveEq : DeriveVisitor
+{
+public:
+  DeriveEq (location_t loc);
+
+  std::vector<std::unique_ptr<AST::Item>> go (Item &item);
+
+private:
+  std::vector<std::unique_ptr<Item>> expanded;
+
+  /**
+   * Create the actual `assert_receiver_is_total_eq` function of the
+   * implementation, which asserts that every type contained within our targeted
+   * type also implements `Eq`.
+   */
+  std::unique_ptr<AssociatedItem>
+  assert_receiver_is_total_eq_fn (std::vector<std::unique_ptr<Type>> &&types);
+
+  /**
+   * Create the Eq trait implementation for a type
+   *
+   * impl Eq for <type> {
+   *     <assert_receiver_is_total_eq>
+   * }
+   *
+   */
+  std::vector<std::unique_ptr<Item>>
+  eq_impls (std::unique_ptr<AssociatedItem> &&fn, std::string name,
+	    const std::vector<std::unique_ptr<GenericParam>> &type_generics);
+
+  /**
+   * Generate the following structure definition
+   *
+   * struct AssertParamIsEq<T: Eq + ?Sized> { _t: PhantomData<T> }
+   */
+  std::unique_ptr<Stmt> assert_param_is_eq ();
+
+  /**
+   * Generate a let statement to assert a type implements `Eq`
+   *
+   * let _: AssertParamIsEq<type>;
+   */
+  std::unique_ptr<Stmt> assert_type_is_eq (std::unique_ptr<Type> &&type);
+
+  virtual void visit_struct (StructStruct &item);
+  virtual void visit_tuple (TupleStruct &item);
+  virtual void visit_enum (Enum &item);
+  virtual void visit_union (Union &item);
+};
+
+} // namespace AST
+} // namespace Rust
+
+#endif // ! RUST_DERIVE_EQ_H