[gcc r15-8817] gccrs: derive(Eq): Create copies of Eq typepath to avoid NodeId confusion

[Arthur Cohen]

https://gcc.gnu.org/g:a4d2184f4305f631eec342b0b5e7fb31981cd31d

commit r15-8817-ga4d2184f4305f631eec342b0b5e7fb31981cd31d
Author: Arthur Cohen <arthur.cohen@embecosm.com>
Date:   Thu Feb 20 09:11:21 2025 +0000

    gccrs: derive(Eq): Create copies of Eq typepath to avoid NodeId confusion
    
    gcc/rust/ChangeLog:
    
            * expand/rust-derive-eq.cc: Copy `Eq` typepath.

Diff:
---
 gcc/rust/expand/rust-derive-eq.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/gcc/rust/expand/rust-derive-eq.cc b/gcc/rust/expand/rust-derive-eq.cc
index 47a8350d2ffc..dc173defd67e 100644
--- a/gcc/rust/expand/rust-derive-eq.cc
+++ b/gcc/rust/expand/rust-derive-eq.cc
@@ -113,13 +113,17 @@ DeriveEq::eq_impls (
   std::unique_ptr<AssociatedItem> &&fn, std::string name,
   const std::vector<std::unique_ptr<GenericParam>> &type_generics)
 {
+  // We create two copies of the type-path to avoid duplicate NodeIds
   auto eq = builder.type_path ({"core", "cmp", "Eq"}, true);
+  auto eq_bound
+    = builder.trait_bound (builder.type_path ({"core", "cmp", "Eq"}, true));
+
   auto steq = builder.type_path (LangItem::Kind::STRUCTURAL_TEQ);
 
   auto trait_items = vec (std::move (fn));
 
   auto eq_generics
-    = setup_impl_generics (name, type_generics, builder.trait_bound (eq));
+    = setup_impl_generics (name, type_generics, std::move (eq_bound));
   auto steq_generics = setup_impl_generics (name, type_generics);
 
   auto eq_impl = builder.trait_impl (eq, std::move (eq_generics.self_type),