Constify BaseType::get_root since this should not change ownership

7 files changed, 33 insertions, 29 deletions

diff --git a/gcc/rust/backend/rust-compile-base.h b/gcc/rust/backend/rust-compile-base.h
index 4a81061..d741598 100644
--- a/gcc/rust/backend/rust-compile-base.h
+++ b/gcc/rust/backend/rust-compile-base.h
@@ -205,14 +205,14 @@ protected:
 			      TyTy::BaseType *expected, Location locus);
 
   Bexpression *coerce_to_dyn_object (Bexpression *compiled_ref,
-				     TyTy::BaseType *actual,
-				     TyTy::BaseType *expected,
-				     TyTy::DynamicObjectType *ty,
+				     const TyTy::BaseType *actual,
+				     const TyTy::BaseType *expected,
+				     const TyTy::DynamicObjectType *ty,
 				     Location locus);
 
   Bexpression *
   compute_address_for_trait_item (const Resolver::TraitItemReference *ref,
-				  TyTy::BaseType *receiver);
+				  const TyTy::BaseType *receiver);
 };
 
 } // namespace Compile
diff --git a/gcc/rust/backend/rust-compile-implitem.h b/gcc/rust/backend/rust-compile-implitem.h
index 1d3ad02..ace5e4c 100644
--- a/gcc/rust/backend/rust-compile-implitem.h
+++ b/gcc/rust/backend/rust-compile-implitem.h
@@ -34,7 +34,7 @@ class CompileInherentImplItem : public HIRCompileBase
   using Rust::Compile::HIRCompileBase::visit;
 
 public:
-  static Bexpression *Compile (TyTy::BaseType *self, HIR::ImplItem *item,
+  static Bexpression *Compile (const TyTy::BaseType *self, HIR::ImplItem *item,
 			       Context *ctx, bool compile_fns,
 			       TyTy::BaseType *concrete = nullptr,
 			       bool is_query_mode = false,
@@ -309,14 +309,15 @@ public:
   }
 
 private:
-  CompileInherentImplItem (TyTy::BaseType *self, Context *ctx, bool compile_fns,
-			   TyTy::BaseType *concrete, Location ref_locus)
+  CompileInherentImplItem (const TyTy::BaseType *self, Context *ctx,
+			   bool compile_fns, TyTy::BaseType *concrete,
+			   Location ref_locus)
     : HIRCompileBase (ctx), self (self), compile_fns (compile_fns),
       concrete (concrete), reference (ctx->get_backend ()->error_expression ()),
       ref_locus (ref_locus)
   {}
 
-  TyTy::BaseType *self;
+  const TyTy::BaseType *self;
   bool compile_fns;
   TyTy::BaseType *concrete;
   Bexpression *reference;
diff --git a/gcc/rust/backend/rust-compile.cc b/gcc/rust/backend/rust-compile.cc
index 23a035f..56d3e40 100644
--- a/gcc/rust/backend/rust-compile.cc
+++ b/gcc/rust/backend/rust-compile.cc
@@ -234,8 +234,8 @@ CompileExpr::visit (HIR::MethodCallExpr &expr)
 
   if (is_dyn_dispatch)
     {
-      TyTy::DynamicObjectType *dyn
-	= static_cast<TyTy::DynamicObjectType *> (receiver->get_root ());
+      const TyTy::DynamicObjectType *dyn
+	= static_cast<const TyTy::DynamicObjectType *> (receiver->get_root ());
 
       size_t offs = 0;
       const Resolver::TraitItemReference *ref = nullptr;
@@ -763,8 +763,8 @@ HIRCompileBase::coercion_site (Bexpression *compiled_ref,
   if (root_expected_kind == TyTy::TypeKind::DYNAMIC
       && root_actual_kind != TyTy::TypeKind::DYNAMIC)
     {
-      TyTy::DynamicObjectType *dyn
-	= static_cast<TyTy::DynamicObjectType *> (expected->get_root ());
+      const TyTy::DynamicObjectType *dyn
+	= static_cast<const TyTy::DynamicObjectType *> (expected->get_root ());
       return coerce_to_dyn_object (compiled_ref, actual, expected, dyn, locus);
     }
 
@@ -773,9 +773,9 @@ HIRCompileBase::coercion_site (Bexpression *compiled_ref,
 
 Bexpression *
 HIRCompileBase::coerce_to_dyn_object (Bexpression *compiled_ref,
-				      TyTy::BaseType *actual,
-				      TyTy::BaseType *expected,
-				      TyTy::DynamicObjectType *ty,
+				      const TyTy::BaseType *actual,
+				      const TyTy::BaseType *expected,
+				      const TyTy::DynamicObjectType *ty,
 				      Location locus)
 {
   Btype *dynamic_object = TyTyResolveCompile::compile (ctx, ty);
@@ -814,7 +814,7 @@ HIRCompileBase::coerce_to_dyn_object (Bexpression *compiled_ref,
   std::vector<Resolver::Adjustment> adjustments;
   while (e->get_kind () == TyTy::TypeKind::REF)
     {
-      auto r = static_cast<TyTy::ReferenceType *> (e);
+      auto r = static_cast<const TyTy::ReferenceType *> (e);
       e = r->get_base ();
 
       if (r->is_mutable ())
@@ -845,7 +845,8 @@ HIRCompileBase::coerce_to_dyn_object (Bexpression *compiled_ref,
 
 Bexpression *
 HIRCompileBase::compute_address_for_trait_item (
-  const Resolver::TraitItemReference *trait_item_ref, TyTy::BaseType *receiver)
+  const Resolver::TraitItemReference *trait_item_ref,
+  const TyTy::BaseType *receiver)
 {
   TyTy::BaseType *item_type = trait_item_ref->get_tyty ();
   rust_assert (item_type->get_kind () == TyTy::TypeKind::FNDEF);
diff --git a/gcc/rust/typecheck/rust-hir-dot-operator.h b/gcc/rust/typecheck/rust-hir-dot-operator.h
index 279e67f..9c0cc43 100644
--- a/gcc/rust/typecheck/rust-hir-dot-operator.h
+++ b/gcc/rust/typecheck/rust-hir-dot-operator.h
@@ -35,10 +35,10 @@ class MethodResolution
 {
 public:
   static PathProbeCandidate *
-  Select (std::vector<PathProbeCandidate> &candidates, TyTy::BaseType *receiver,
-	  std::vector<Adjustment> &adjustments)
+  Select (std::vector<PathProbeCandidate> &candidates,
+	  const TyTy::BaseType *receiver, std::vector<Adjustment> &adjustments)
   {
-    TyTy::BaseType *r = receiver;
+    const TyTy::BaseType *r = receiver;
     while (true)
       {
 	PathProbeCandidate *c = nullptr;
@@ -80,7 +80,8 @@ public:
 	// FIXME this needs to use deref trait and fall back to unsized to
 	// remove array syntax
 
-	TyTy::ReferenceType *rr = static_cast<TyTy::ReferenceType *> (r);
+	const TyTy::ReferenceType *rr
+	  = static_cast<const TyTy::ReferenceType *> (r);
 	r = rr->get_base ();
 	adjustments.push_back (
 	  Adjustment (Adjustment::AdjustmentType::DEREF_REF, r));
diff --git a/gcc/rust/typecheck/rust-hir-type-check-expr.h b/gcc/rust/typecheck/rust-hir-type-check-expr.h
index b386763..83fafa6 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-expr.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-expr.h
@@ -219,7 +219,7 @@ public:
 
     // in order to probe of the correct type paths we need the root type, which
     // strips any references
-    TyTy::BaseType *root = receiver_tyty->get_root ();
+    const TyTy::BaseType *root = receiver_tyty->get_root ();
 
     // https://doc.rust-lang.org/reference/expressions/method-call-expr.html
     // method resolution is complex in rust once we start handling generics and
@@ -297,7 +297,7 @@ public:
 
     if (root->get_kind () == TyTy::TypeKind::ADT)
       {
-	TyTy::ADTType *adt = static_cast<TyTy::ADTType *> (root);
+	const TyTy::ADTType *adt = static_cast<const TyTy::ADTType *> (root);
 	if (adt->has_substitutions () && fn->needs_substitution ())
 	  {
 	    // consider the case where we have:
@@ -322,7 +322,8 @@ public:
 	    auto s = fn->get_self_type ()->get_root ();
 	    rust_assert (s->can_eq (adt, false));
 	    rust_assert (s->get_kind () == TyTy::TypeKind::ADT);
-	    TyTy::ADTType *self_adt = static_cast<TyTy::ADTType *> (s);
+	    const TyTy::ADTType *self_adt
+	      = static_cast<const TyTy::ADTType *> (s);
 
 	    // we need to grab the Self substitutions as the inherit type
 	    // parameters for this
diff --git a/gcc/rust/typecheck/rust-tyty.cc b/gcc/rust/typecheck/rust-tyty.cc
index 22255d9..969360e 100644
--- a/gcc/rust/typecheck/rust-tyty.cc
+++ b/gcc/rust/typecheck/rust-tyty.cc
@@ -114,13 +114,13 @@ BaseType::inherit_bounds (
     }
 }
 
-BaseType *
-BaseType::get_root ()
+const BaseType *
+BaseType::get_root () const
 {
-  BaseType *root = this;
+  const BaseType *root = this;
   while (root->get_kind () == TyTy::REF)
     {
-      ReferenceType *r = static_cast<ReferenceType *> (root);
+      const ReferenceType *r = static_cast<const ReferenceType *> (root);
       root = r->get_base ();
     }
   return root;
diff --git a/gcc/rust/typecheck/rust-tyty.h b/gcc/rust/typecheck/rust-tyty.h
index 0e74d49..f726069 100644
--- a/gcc/rust/typecheck/rust-tyty.h
+++ b/gcc/rust/typecheck/rust-tyty.h
@@ -337,7 +337,7 @@ public:
 		debug_str ().c_str ());
   }
 
-  BaseType *get_root ();
+  const BaseType *get_root () const;
 
 protected:
   BaseType (HirId ref, HirId ty_ref, TypeKind kind,