[gcc r14-8581] gccrs: Make feature gate visitor inherit from default one

[Arthur Cohen]

https://gcc.gnu.org/g:9f6d3010047d417f54c439db42f111fa61b216df

commit r14-8581-g9f6d3010047d417f54c439db42f111fa61b216df
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Fri Nov 24 11:17:52 2023 +0100

    gccrs: Make feature gate visitor inherit from default one
    
    The feature gating behavior may be shortened and kept cleaner using the
    default visitor. This means less maintenance on visit functions as the
    traversal is shared by multiple visitors.
    
    gcc/rust/ChangeLog:
    
            * checks/errors/rust-feature-gate.cc (FeatureGate::visit): Add a visit
            function for the crate level.
            (FeatureGate::check): Add call to crate visit.
            * checks/errors/rust-feature-gate.h (class FeatureGate): Remove now
            useless visit functions (traversal only).
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/rust/checks/errors/rust-feature-gate.cc | 37 +++++++----------------------
 gcc/rust/checks/errors/rust-feature-gate.h  |  7 +++---
 2 files changed, 13 insertions(+), 31 deletions(-)

diff --git a/gcc/rust/checks/errors/rust-feature-gate.cc b/gcc/rust/checks/errors/rust-feature-gate.cc
index a531d0370f00..3c943022f05e 100644
--- a/gcc/rust/checks/errors/rust-feature-gate.cc
+++ b/gcc/rust/checks/errors/rust-feature-gate.cc
@@ -18,11 +18,18 @@
 
 #include "rust-feature-gate.h"
 #include "rust-abi.h"
+#include "rust-ast-visitor.h"
 
 namespace Rust {
 
 void
 FeatureGate::check (AST::Crate &crate)
+{
+  visit (crate);
+}
+
+void
+FeatureGate::visit (AST::Crate &crate)
 {
   valid_features.clear ();
 
@@ -56,12 +63,7 @@ FeatureGate::check (AST::Crate &crate)
 	}
     }
 
-  auto &items = crate.items;
-  for (auto it = items.begin (); it != items.end (); it++)
-    {
-      auto &item = *it;
-      item->accept_vis (*this);
-    }
+  AST::DefaultASTVisitor::visit (crate);
 }
 
 void
@@ -103,10 +105,7 @@ FeatureGate::visit (AST::ExternBlock &block)
 	gate (Feature::Name::INTRINSICS, block.get_locus (),
 	      "intrinsics are subject to change");
     }
-  for (const auto &item : block.get_extern_items ())
-    {
-      item->accept_vis (*this);
-    }
+  AST::DefaultASTVisitor::visit (block);
 }
 
 void
@@ -129,24 +128,6 @@ FeatureGate::visit (AST::MacroRulesDefinition &rules_def)
   check_rustc_attri (rules_def.get_outer_attrs ());
 }
 
-void
-FeatureGate::visit (AST::InherentImpl &impl)
-{
-  for (const auto &item : impl.get_impl_items ())
-    {
-      item->accept_vis (*this);
-    }
-}
-
-void
-FeatureGate::visit (AST::TraitImpl &impl)
-{
-  for (const auto &item : impl.get_impl_items ())
-    {
-      item->accept_vis (*this);
-    }
-}
-
 void
 FeatureGate::visit (AST::Function &function)
 {
diff --git a/gcc/rust/checks/errors/rust-feature-gate.h b/gcc/rust/checks/errors/rust-feature-gate.h
index 1ebd3c9e05fb..8d1a26a13619 100644
--- a/gcc/rust/checks/errors/rust-feature-gate.h
+++ b/gcc/rust/checks/errors/rust-feature-gate.h
@@ -25,12 +25,15 @@
 
 namespace Rust {
 
-class FeatureGate : public AST::ASTVisitor
+class FeatureGate : public AST::DefaultASTVisitor
 {
 public:
   FeatureGate () {}
 
+  using AST::DefaultASTVisitor::visit;
+
   void check (AST::Crate &crate);
+  void visit (AST::Crate &crate) override;
 
   void visit (AST::Token &tok) override {}
   void visit (AST::DelimTokenTree &delim_tok_tree) override {}
@@ -127,8 +130,6 @@ public:
   void visit (AST::TraitItemConst &item) override {}
   void visit (AST::TraitItemType &item) override {}
   void visit (AST::Trait &trait) override {}
-  void visit (AST::InherentImpl &impl) override;
-  void visit (AST::TraitImpl &impl) override;
   void visit (AST::ExternalTypeItem &item) override;
   void visit (AST::ExternalStaticItem &item) override {}
   void visit (AST::ExternalFunctionItem &item) override {}