gccrs: Change singleton returned type to a reference

We do not need a raw pointer for this singleton,
nor we need having it on the heap through a
smart pointer.

gcc/rust/ChangeLog:

	* ast/rust-ast.h: Change dereference from a pointer to a reference
	accessor.
	* ast/rust-expr.h: Likewise.
	* ast/rust-item.h: Likewise.
	* ast/rust-macro.h: Likewise.
	* ast/rust-path.h: Likewise.
	* ast/rust-pattern.h: Likewise.
	* ast/rust-type.h: Likewise.
	* backend/rust-compile-base.cc (HIRCompileBase::resolve_method_address):
	Likewise.
	* backend/rust-compile-context.h: Likewise.
	* backend/rust-compile-expr.cc (CompileExpr::visit): Likewise.
	(CompileExpr::generate_closure_function): Likewise.
	* backend/rust-compile-extern.h: Likewise.
	* backend/rust-compile-implitem.cc (CompileTraitItem::visit): Likewise.
	* backend/rust-compile-intrinsic.cc (Intrinsics::compile): Likewise.
	* backend/rust-compile-item.cc (CompileItem::visit): Likewise.
	* backend/rust-compile-resolve-path.cc (ResolvePathRef::resolve):
	Likewise.
	(HIRCompileBase::query_compile): Likewise.
	* backend/rust-compile-type.cc (TyTyResolveCompile::visit): Likewise.
	(TyTyResolveCompile::create_dyn_obj_record): Likewise.
	* backend/rust-compile.cc (HIRCompileBase::coerce_to_dyn_object):
	Likewise.
	* backend/rust-mangle-v0.cc (v0_path): Likewise.
	(v0_mangle_item): Likewise.
	* checks/errors/borrowck/rust-borrow-checker.cc (BorrowChecker::go):
	Likewise.
	* checks/errors/privacy/rust-privacy-check.cc (Resolver::resolve):
	Likewise.
	* checks/errors/rust-const-checker.cc (ConstChecker::ConstChecker):
	Likewise.
	* checks/errors/rust-unsafe-checker.cc (UnsafeChecker::UnsafeChecker):
	Likewise.
	* checks/lints/rust-lint-marklive-base.h: Likewise.
	* checks/lints/rust-lint-marklive.cc (MarkLive::go): Likewise.
	(MarkLive::visit): Likewise.
	(MarkLive::visit_path_segment): Likewise.
	* checks/lints/rust-lint-marklive.h: Likewise.
	* checks/lints/rust-lint-scan-deadcode.h: Likewise.
	* expand/rust-macro-expand.cc (MacroExpander::expand_invoc): Likewise.
	* expand/rust-macro-expand.h (struct MacroExpander): Change mapping
	from pointer to a reference.
	* expand/rust-proc-macro.cc (BangProcMacro::BangProcMacro): Replace
	pointer accessor with reference accessor.
	(AttributeProcMacro::AttributeProcMacro): Likewise.
	(CustomDeriveProcMacro::CustomDeriveProcMacro): Likewise.
	* hir/rust-ast-lower-base.cc (ASTLoweringBase::lower_lifetime):
	Likewise.
	(ASTLoweringBase::lower_loop_label): Likewise.
	(ASTLoweringBase::lower_path_expr_seg): Likewise.
	(ASTLoweringBase::lower_self): Likewise.
	(ASTLoweringBase::handle_lang_item_attribute): Likewise.
	(ASTLoweringBase::lower_extern_block): Likewise.
	(ASTLoweringBase::lower_macro_definition): Likewise.
	* hir/rust-ast-lower-base.h: Likewise.
	* hir/rust-ast-lower-block.h: Likewise.
	* hir/rust-ast-lower-enumitem.h: Likewise.
	* hir/rust-ast-lower-expr.cc (ASTLoweringExpr::translate): Likewise.
	(ASTLoweringExpr::visit): Likewise.
	* hir/rust-ast-lower-extern.h: Likewise.
	* hir/rust-ast-lower-implitem.cc (ASTLowerImplItem::translate):
	Likewise.
	(ASTLowerImplItem::visit): Likewise.
	(ASTLowerTraitItem::translate): Likewise.
	(ASTLowerTraitItem::visit): Likewise.
	* hir/rust-ast-lower-item.cc (ASTLoweringItem::translate): Likewise.
	(ASTLoweringItem::visit): Likewise.
	(ASTLoweringSimplePath::lower): Likewise.
	* hir/rust-ast-lower-pattern.cc (ASTLoweringPattern::translate):
	Likewise.
	(ASTLoweringPattern::visit): Likewise.
	* hir/rust-ast-lower-stmt.cc (ASTLoweringStmt::translate): Likewise.
	(ASTLoweringStmt::visit): Likewise.
	* hir/rust-ast-lower-struct-field-expr.h: Likewise.
	* hir/rust-ast-lower-type.cc (ASTLowerTypePath::visit): Likewise.
	(ASTLowerQualifiedPathInType::visit): Likewise.
	(ASTLoweringType::translate): Likewise.
	(ASTLoweringType::visit): Likewise.
	(ASTLowerGenericParam::translate): Likewise.
	(ASTLowerGenericParam::visit): Likewise.
	(ASTLoweringTypeBounds::translate): Likewise.
	(ASTLoweringTypeBounds::visit): Likewise.
	(ASTLowerWhereClauseItem::translate): Likewise.
	(ASTLowerWhereClauseItem::visit): Likewise.
	* hir/rust-ast-lower.cc (ASTLowering::go): Likewise.
	(ASTLoweringBlock::visit): Likewise.
	(ASTLoweringIfBlock::visit): Likewise.
	(ASTLoweringIfLetBlock::visit): Likewise.
	(ASTLowerStructExprField::visit): Likewise.
	(ASTLoweringExprWithBlock::visit): Likewise.
	(ASTLowerPathInExpression::visit): Likewise.
	(ASTLoweringBase::lower_qual_path_type): Likewise.
	(ASTLowerQualPathInExpression::visit): Likewise.
	* metadata/rust-export-metadata.cc (ExportContext::emit_trait):
	Likewise.
	(ExportContext::emit_function): Likewise.
	(ExportContext::emit_macro): Likewise.
	(PublicInterface::PublicInterface): Likewise.
	(PublicInterface::expected_metadata_filename): Likewise.
	* metadata/rust-export-metadata.h: Likewise.
	* resolve/rust-ast-resolve-base.h: Likewise.
	* resolve/rust-ast-resolve-implitem.h: Likewise.
	* resolve/rust-ast-resolve-item.cc (ResolveTraitItems::visit):
	Likewise.
	(ResolveItem::visit): Likewise.
	(ResolveExternItem::visit): Likewise.
	* resolve/rust-ast-resolve-path.cc (ResolvePath::resolve_path):
	Likewise.
	* resolve/rust-ast-resolve-stmt.h: Likewise.
	* resolve/rust-ast-resolve-toplevel.h: Likewise.
	* resolve/rust-ast-resolve-type.cc (ResolveRelativeTypePath::go):
	Likewise.
	(ResolveTypeToCanonicalPath::visit): Likewise.
	* resolve/rust-ast-resolve-type.h: Likewise.
	* resolve/rust-ast-resolve.cc (NameResolution::NameResolution):
	Likewise.
	(NameResolution::go): Likewise.
	* resolve/rust-ast-resolve.h: Likewise.
	* resolve/rust-early-name-resolver-2.0.cc (Early::visit_attributes):
	Likewise.
	* resolve/rust-early-name-resolver.cc (EarlyNameResolver::EarlyNameResolver):
	Likewise.
	* resolve/rust-late-name-resolver-2.0.cc (next_node_id): Likewise.
	(next_hir_id): Likewise.
	* resolve/rust-name-resolution-context.cc (NameResolutionContext::NameResolutionContext):
	Likewise.
	* resolve/rust-name-resolver.cc (Resolver::Resolver): Likewise.
	(Resolver::generate_builtins): Likewise.
	(Resolver::setup_builtin): Likewise.
	* resolve/rust-name-resolver.h: Likewise.
	* resolve/rust-toplevel-name-resolver-2.0.cc (TopLevel::visit):
	Likewise.
	(TopLevel::handle_use_glob): Likewise.
	* rust-session-manager.cc (Session::get_instance): Likewise.
	(Session::handle_input_files): Likewise.
	(Session::handle_crate_name): Likewise.
	(Session::compile_crate): Likewise.
	(Session::load_extern_crate): Likewise.
	* rust-session-manager.h: Likewise.
	* typecheck/rust-autoderef.cc (Adjuster::try_unsize_type): Likewise.
	* typecheck/rust-coercion.cc (TypeCoercionRules::do_coercion):
	Likewise.
	(TypeCoercionRules::coerce_unsafe_ptr): Likewise.
	(TypeCoercionRules::coerce_borrowed_pointer): Likewise.
	(TypeCoercionRules::coerce_unsized): Likewise.
	* typecheck/rust-coercion.h: Likewise.
	* typecheck/rust-hir-dot-operator.cc (MethodResolver::select):
	Likewise.
	* typecheck/rust-hir-inherent-impl-overlap.h: Likewise.
	* typecheck/rust-hir-path-probe.cc (PathProbeType::process_enum_item_for_candiates):
	Likewise.
	(PathProbeType::process_impl_items_for_candidates): Likewise.
	(PathProbeImplTrait::process_trait_impl_items_for_candidates):
	Likewise.
	* typecheck/rust-hir-trait-resolve.cc (TraitResolver::resolve_path_to_trait):
	Likewise.
	(TraitItemReference::get_parent_trait_mappings): Likewise.
	* typecheck/rust-hir-type-check-base.cc (TypeCheckBase::resolve_literal):
	Likewise.
	(TypeCheckBase::get_marker_predicate): Likewise.
	* typecheck/rust-hir-type-check-base.h: Likewise.
	* typecheck/rust-hir-type-check-enumitem.cc (TypeCheckEnumItem::visit):
	Likewise.
	* typecheck/rust-hir-type-check-expr.cc (TypeCheckExpr::visit):
	Likewise.
	(TypeCheckExpr::resolve_operator_overload): Likewise.
	(TypeCheckExpr::resolve_fn_trait_call): Likewise.
	* typecheck/rust-hir-type-check-implitem.cc (TypeCheckTopLevelExternItem::visit):
	Likewise.
	(TypeCheckImplItem::visit): Likewise.
	* typecheck/rust-hir-type-check-item.cc (TypeCheckItem::visit):
	Likewise.
	* typecheck/rust-hir-type-check-path.cc (TypeCheckExpr::resolve_root_path):
	Likewise.
	(TypeCheckExpr::resolve_segments): Likewise.
	* typecheck/rust-hir-type-check-pattern.cc (TypeCheckPattern::emit_pattern_size_error):
	Likewise.
	(ClosureParamInfer::Resolve): Likewise.
	* typecheck/rust-hir-type-check-struct.cc (TypeCheckStructExpr::resolve):
	Likewise.
	* typecheck/rust-hir-type-check-type.cc (TypeCheckType::visit): Likewise.
	(TypeCheckType::resolve_root_path): Likewise.
	(TypeResolveGenericParam::visit): Likewise.
	(ResolveWhereClauseItem::visit): Likewise.
	* typecheck/rust-hir-type-check.cc (TraitItemReference::get_type_from_fn):
	Likewise.
	* typecheck/rust-type-util.cc (query_type): Likewise.
	* typecheck/rust-typecheck-context.cc (TypeCheckContext::compute_inference_variables):
	Likewise.
	* typecheck/rust-tyty-bounds.cc (TypeBoundsProbe::scan): Likewise.
	(TypeBoundsProbe::assemble_builtin_candidate): Likewise.
	(TypeCheckBase::get_predicate_from_bound): Likewise.
	* typecheck/rust-tyty-call.cc (TypeCheckCallExpr::visit): Likewise.
	(TypeCheckMethodCallExpr::check): Likewise.
	* typecheck/rust-tyty-call.h: Likewise.
	* typecheck/rust-tyty-cmp.h: Likewise.
	* typecheck/rust-tyty-subst.cc (SubstitutionParamMapping::override_context):
	Likewise.
	(SubstitutionRef::monomorphize): Likewise.
	* typecheck/rust-tyty-util.cc (TyVar::get_implicit_infer_var):
	Likewise.
	(TyVar::monomorphized_clone): Likewise.
	(TyWithLocation::TyWithLocation): Likewise.
	* typecheck/rust-tyty.cc (BaseType::satisfies_bound): Likewise.
	(InferType::clone): Likewise.
	(ADTType::handle_substitions): Likewise.
	(TupleType::handle_substitions): Likewise.
	(FnType::handle_substitions): Likewise.
	(ClosureType::setup_fn_once_output): Likewise.
	(ArrayType::handle_substitions): Likewise.
	(SliceType::handle_substitions): Likewise.
	(ReferenceType::handle_substitions): Likewise.
	(PointerType::handle_substitions): Likewise.
	(ParamType::handle_substitions): Likewise.
	* typecheck/rust-tyty.h: Likewise.
	* typecheck/rust-unify.cc (UnifyRules::UnifyRules): Likewise.
	(UnifyRules::commit): Likewise.
	* util/rust-hir-map.cc: Change getter return type to a reference.
	* util/rust-hir-map.h: Update function's prototype.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

11 files changed, 50 insertions, 50 deletions

diff --git a/gcc/rust/backend/rust-compile-base.cc b/gcc/rust/backend/rust-compile-base.cc
index 67d8797..e313820 100644
--- a/gcc/rust/backend/rust-compile-base.cc
+++ b/gcc/rust/backend/rust-compile-base.cc
@@ -877,7 +877,7 @@ HIRCompileBase::resolve_method_address (TyTy::FnType *fntype,
   // Now we can try and resolve the address since this might be a forward
   // declared function, generic function which has not be compiled yet or
   // its an not yet trait bound function
-  HIR::Item *resolved_item = ctx->get_mappings ()->lookup_defid (id);
+  HIR::Item *resolved_item = ctx->get_mappings ().lookup_defid (id);
   if (resolved_item != nullptr)
     {
       if (!fntype->has_substitutions_defined ())
@@ -888,8 +888,8 @@ HIRCompileBase::resolve_method_address (TyTy::FnType *fntype,
 
   // it might be resolved to a trait item
   HIR::TraitItem *trait_item
-    = ctx->get_mappings ()->lookup_trait_item_defid (id);
-  HIR::Trait *trait = ctx->get_mappings ()->lookup_trait_item_mapping (
+    = ctx->get_mappings ().lookup_trait_item_defid (id);
+  HIR::Trait *trait = ctx->get_mappings ().lookup_trait_item_mapping (
     trait_item->get_mappings ().get_hirid ());
 
   Resolver::TraitReference *trait_ref
diff --git a/gcc/rust/backend/rust-compile-context.h b/gcc/rust/backend/rust-compile-context.h
index 156c7b1..a446388 100644
--- a/gcc/rust/backend/rust-compile-context.h
+++ b/gcc/rust/backend/rust-compile-context.h
@@ -89,7 +89,7 @@ public:
 
   Resolver::Resolver *get_resolver () { return resolver; }
   Resolver::TypeCheckContext *get_tyctx () { return tyctx; }
-  Analysis::Mappings *get_mappings () { return mappings; }
+  Analysis::Mappings &get_mappings () { return mappings; }
 
   void push_block (tree scope)
   {
@@ -390,7 +390,7 @@ public:
 private:
   Resolver::Resolver *resolver;
   Resolver::TypeCheckContext *tyctx;
-  Analysis::Mappings *mappings;
+  Analysis::Mappings &mappings;
   Mangler mangler;
 
   // state
diff --git a/gcc/rust/backend/rust-compile-expr.cc b/gcc/rust/backend/rust-compile-expr.cc
index 9ffd863..0980e6c 100644
--- a/gcc/rust/backend/rust-compile-expr.cc
+++ b/gcc/rust/backend/rust-compile-expr.cc
@@ -120,7 +120,7 @@ CompileExpr::visit (HIR::ReturnExpr &expr)
 
       TyTy::BaseType *expected = fncontext.retty;
       location_t lvalue_locus
-	= ctx->get_mappings ()->lookup_location (expected->get_ref ());
+	= ctx->get_mappings ().lookup_location (expected->get_ref ());
 
       TyTy::BaseType *actual = nullptr;
       bool ok = ctx->get_tyctx ()->lookup_type (
@@ -456,7 +456,7 @@ CompileExpr::visit (HIR::StructExprStructFields &struct_expr)
       // process arguments
       auto &argument = struct_expr.get_fields ().at (0);
       auto lvalue_locus
-	= ctx->get_mappings ()->lookup_location (expected->get_ty_ref ());
+	= ctx->get_mappings ().lookup_location (expected->get_ty_ref ());
       auto rvalue_locus = argument->get_locus ();
       auto rvalue = CompileStructExprField::Compile (argument.get (), ctx);
 
@@ -488,7 +488,7 @@ CompileExpr::visit (HIR::StructExprStructFields &struct_expr)
 	  // process arguments
 	  auto &argument = struct_expr.get_fields ().at (i);
 	  auto lvalue_locus
-	    = ctx->get_mappings ()->lookup_location (expected->get_ty_ref ());
+	    = ctx->get_mappings ().lookup_location (expected->get_ty_ref ());
 	  auto rvalue_locus = argument->get_locus ();
 	  auto rvalue = CompileStructExprField::Compile (argument.get (), ctx);
 
@@ -735,7 +735,7 @@ CompileExpr::visit (HIR::BreakExpr &expr)
 	}
 
       HirId ref = UNKNOWN_HIRID;
-      if (!ctx->get_mappings ()->lookup_node_to_hir (resolved_node_id, &ref))
+      if (!ctx->get_mappings ().lookup_node_to_hir (resolved_node_id, &ref))
 	{
 	  rust_fatal_error (expr.get_locus (), "reverse lookup label failure");
 	  return;
@@ -779,7 +779,7 @@ CompileExpr::visit (HIR::ContinueExpr &expr)
 	}
 
       HirId ref = UNKNOWN_HIRID;
-      if (!ctx->get_mappings ()->lookup_node_to_hir (resolved_node_id, &ref))
+      if (!ctx->get_mappings ().lookup_node_to_hir (resolved_node_id, &ref))
 	{
 	  rust_fatal_error (expr.get_locus (), "reverse lookup label failure");
 	  return;
@@ -1153,7 +1153,7 @@ CompileExpr::visit (HIR::CallExpr &expr)
 
 	  // coerce it if required
 	  location_t lvalue_locus
-	    = ctx->get_mappings ()->lookup_location (expected->get_ty_ref ());
+	    = ctx->get_mappings ().lookup_location (expected->get_ty_ref ());
 	  location_t rvalue_locus = argument->get_locus ();
 	  rvalue
 	    = coercion_site (argument->get_mappings ().get_hirid (), rvalue,
@@ -1257,7 +1257,7 @@ CompileExpr::visit (HIR::CallExpr &expr)
 
       // coerce it if required
       location_t lvalue_locus
-	= ctx->get_mappings ()->lookup_location (expected->get_ty_ref ());
+	= ctx->get_mappings ().lookup_location (expected->get_ty_ref ());
       location_t rvalue_locus = argument->get_locus ();
       rvalue = coercion_site (argument->get_mappings ().get_hirid (), rvalue,
 			      actual, expected, lvalue_locus, rvalue_locus);
@@ -1346,7 +1346,7 @@ CompileExpr::visit (HIR::MethodCallExpr &expr)
 
       // coerce it if required
       location_t lvalue_locus
-	= ctx->get_mappings ()->lookup_location (expected->get_ty_ref ());
+	= ctx->get_mappings ().lookup_location (expected->get_ty_ref ());
       location_t rvalue_locus = argument->get_locus ();
       rvalue = coercion_site (argument->get_mappings ().get_hirid (), rvalue,
 			      actual, expected, lvalue_locus, rvalue_locus);
@@ -2175,7 +2175,7 @@ CompileExpr::visit (HIR::ClosureExpr &expr)
     {
       // lookup the HirId
       HirId ref = UNKNOWN_HIRID;
-      bool ok = ctx->get_mappings ()->lookup_node_to_hir (capture, &ref);
+      bool ok = ctx->get_mappings ().lookup_node_to_hir (capture, &ref);
       rust_assert (ok);
 
       // lookup the var decl
@@ -2209,7 +2209,7 @@ CompileExpr::generate_closure_function (HIR::ClosureExpr &expr,
   const Resolver::CanonicalPath &parent_canonical_path
     = closure_tyty.get_ident ().path;
   NodeId node_id;
-  bool ok = ctx->get_mappings ()->lookup_hir_to_node (
+  bool ok = ctx->get_mappings ().lookup_hir_to_node (
     expr.get_mappings ().get_hirid (), &node_id);
   rust_assert (ok);
   Resolver::CanonicalPath path = parent_canonical_path.append (
@@ -2245,7 +2245,7 @@ CompileExpr::generate_closure_function (HIR::ClosureExpr &expr,
     {
       // lookup the HirId
       HirId ref = UNKNOWN_HIRID;
-      bool ok = ctx->get_mappings ()->lookup_node_to_hir (capture, &ref);
+      bool ok = ctx->get_mappings ().lookup_node_to_hir (capture, &ref);
       rust_assert (ok);
 
       // get the assessor
diff --git a/gcc/rust/backend/rust-compile-extern.h b/gcc/rust/backend/rust-compile-extern.h
index 7dbf7d7..f596ed2 100644
--- a/gcc/rust/backend/rust-compile-extern.h
+++ b/gcc/rust/backend/rust-compile-extern.h
@@ -135,7 +135,7 @@ public:
       {
 	// then we need to get the canonical path of it and mangle it
 	const Resolver::CanonicalPath *canonical_path = nullptr;
-	bool ok = ctx->get_mappings ()->lookup_canonical_path (
+	bool ok = ctx->get_mappings ().lookup_canonical_path (
 	  function.get_mappings ().get_nodeid (), &canonical_path);
 	rust_assert (ok);
 
diff --git a/gcc/rust/backend/rust-compile-implitem.cc b/gcc/rust/backend/rust-compile-implitem.cc
index 7435833..0f24417 100644
--- a/gcc/rust/backend/rust-compile-implitem.cc
+++ b/gcc/rust/backend/rust-compile-implitem.cc
@@ -28,7 +28,7 @@ CompileTraitItem::visit (HIR::TraitItemConst &constant)
   TyTy::BaseType *resolved_type = concrete;
 
   const Resolver::CanonicalPath *canonical_path = nullptr;
-  bool ok = ctx->get_mappings ()->lookup_canonical_path (
+  bool ok = ctx->get_mappings ().lookup_canonical_path (
     constant.get_mappings ().get_nodeid (), &canonical_path);
   rust_assert (ok);
 
@@ -78,7 +78,7 @@ CompileTraitItem::visit (HIR::TraitItemFunc &func)
     }
 
   const Resolver::CanonicalPath *canonical_path = nullptr;
-  bool ok = ctx->get_mappings ()->lookup_canonical_path (
+  bool ok = ctx->get_mappings ().lookup_canonical_path (
     func.get_mappings ().get_nodeid (), &canonical_path);
   rust_assert (ok);
 
diff --git a/gcc/rust/backend/rust-compile-intrinsic.cc b/gcc/rust/backend/rust-compile-intrinsic.cc
index f94659c..de3bb6e 100644
--- a/gcc/rust/backend/rust-compile-intrinsic.cc
+++ b/gcc/rust/backend/rust-compile-intrinsic.cc
@@ -269,7 +269,7 @@ Intrinsics::compile (TyTy::FnType *fntype)
   if (it != generic_intrinsics.end ())
     return it->second (ctx, fntype);
 
-  location_t locus = ctx->get_mappings ()->lookup_location (fntype->get_ref ());
+  location_t locus = ctx->get_mappings ().lookup_location (fntype->get_ref ());
   rust_error_at (locus, ErrorCode::E0093,
 		 "unrecognized intrinsic function: %qs",
 		 fntype->get_identifier ().c_str ());
diff --git a/gcc/rust/backend/rust-compile-item.cc b/gcc/rust/backend/rust-compile-item.cc
index 7c62adc..9d65b61 100644
--- a/gcc/rust/backend/rust-compile-item.cc
+++ b/gcc/rust/backend/rust-compile-item.cc
@@ -43,7 +43,7 @@ CompileItem::visit (HIR::StaticItem &var)
   tree type = TyTyResolveCompile::compile (ctx, resolved_type);
 
   const Resolver::CanonicalPath *canonical_path = nullptr;
-  ok = ctx->get_mappings ()->lookup_canonical_path (
+  ok = ctx->get_mappings ().lookup_canonical_path (
     var.get_mappings ().get_nodeid (), &canonical_path);
   rust_assert (ok);
 
@@ -103,8 +103,8 @@ CompileItem::visit (HIR::ConstantItem &constant)
   else
     {
       const Resolver::CanonicalPath *canonical_path_ptr = nullptr;
-      ok = ctx->get_mappings ()->lookup_canonical_path (mappings.get_nodeid (),
-							&canonical_path_ptr);
+      ok = ctx->get_mappings ().lookup_canonical_path (mappings.get_nodeid (),
+						       &canonical_path_ptr);
       rust_assert (ok);
       canonical_path = *canonical_path_ptr;
     }
@@ -155,7 +155,7 @@ CompileItem::visit (HIR::Function &function)
       HirId parent_impl_block = UNKNOWN_HIRID;
       HirId id = function.get_mappings ().get_hirid ();
       HIR::ImplItem *impl_item
-	= ctx->get_mappings ()->lookup_hir_implitem (id, &parent_impl_block);
+	= ctx->get_mappings ().lookup_hir_implitem (id, &parent_impl_block);
       if (impl_item != nullptr)
 	{
 	  Resolver::AssociatedImplTrait *impl = nullptr;
@@ -182,7 +182,7 @@ CompileItem::visit (HIR::Function &function)
   else
     {
       const Resolver::CanonicalPath *path = nullptr;
-      bool ok = ctx->get_mappings ()->lookup_canonical_path (
+      bool ok = ctx->get_mappings ().lookup_canonical_path (
 	function.get_mappings ().get_nodeid (), &path);
       rust_assert (ok);
 
diff --git a/gcc/rust/backend/rust-compile-resolve-path.cc b/gcc/rust/backend/rust-compile-resolve-path.cc
index 91f2deb..ea8bb5b 100644
--- a/gcc/rust/backend/rust-compile-resolve-path.cc
+++ b/gcc/rust/backend/rust-compile-resolve-path.cc
@@ -126,7 +126,7 @@ ResolvePathRef::resolve (const HIR::PathIdentSegment &final_segment,
     }
 
   HirId ref;
-  if (!ctx->get_mappings ()->lookup_node_to_hir (ref_node_id, &ref))
+  if (!ctx->get_mappings ().lookup_node_to_hir (ref_node_id, &ref))
     {
       rust_error_at (expr_locus, "reverse call path lookup failure");
       return error_mark_node;
@@ -199,10 +199,10 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 			       const Analysis::NodeMapping &mappings,
 			       location_t expr_locus, bool is_qualified_path)
 {
-  HIR::Item *resolved_item = ctx->get_mappings ()->lookup_hir_item (ref);
+  HIR::Item *resolved_item = ctx->get_mappings ().lookup_hir_item (ref);
   HirId parent_block;
   HIR::ExternalItem *resolved_extern_item
-    = ctx->get_mappings ()->lookup_hir_extern_item (ref, &parent_block);
+    = ctx->get_mappings ().lookup_hir_extern_item (ref, &parent_block);
   bool is_hir_item = resolved_item != nullptr;
   bool is_hir_extern_item = resolved_extern_item != nullptr;
   bool is_fn = lookup->get_kind () == TyTy::TypeKind::FNDEF;
@@ -242,7 +242,7 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 
       HirId parent_impl_id = UNKNOWN_HIRID;
       HIR::ImplItem *resolved_item
-	= ctx->get_mappings ()->lookup_hir_implitem (ref, &parent_impl_id);
+	= ctx->get_mappings ().lookup_hir_implitem (ref, &parent_impl_id);
       bool is_impl_item = resolved_item != nullptr;
       if (is_impl_item)
 	{
@@ -257,8 +257,8 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 	{
 	  // it might be resolved to a trait item
 	  HIR::TraitItem *trait_item
-	    = ctx->get_mappings ()->lookup_hir_trait_item (ref);
-	  HIR::Trait *trait = ctx->get_mappings ()->lookup_trait_item_mapping (
+	    = ctx->get_mappings ().lookup_hir_trait_item (ref);
+	  HIR::Trait *trait = ctx->get_mappings ().lookup_trait_item_mapping (
 	    trait_item->get_mappings ().get_hirid ());
 
 	  Resolver::TraitReference *trait_ref
diff --git a/gcc/rust/backend/rust-compile-type.cc b/gcc/rust/backend/rust-compile-type.cc
index bfc2464..4b42cef 100644
--- a/gcc/rust/backend/rust-compile-type.cc
+++ b/gcc/rust/backend/rust-compile-type.cc
@@ -147,7 +147,7 @@ TyTyResolveCompile::visit (const TyTy::PlaceholderType &type)
 void
 TyTyResolveCompile::visit (const TyTy::ClosureType &type)
 {
-  auto mappings = ctx->get_mappings ();
+  auto &mappings = ctx->get_mappings ();
 
   std::vector<Backend::typed_identifier> fields;
 
@@ -156,7 +156,7 @@ TyTyResolveCompile::visit (const TyTy::ClosureType &type)
     {
       // lookup the HirId
       HirId ref = UNKNOWN_HIRID;
-      bool ok = mappings->lookup_node_to_hir (capture, &ref);
+      bool ok = mappings.lookup_node_to_hir (capture, &ref);
       rust_assert (ok);
 
       // lookup the var decl type
@@ -201,7 +201,7 @@ TyTyResolveCompile::visit (const TyTy::FnType &type)
     {
       auto ret = TyTyResolveCompile::compile (ctx, hir_type, trait_object_mode);
       location_t return_type_locus
-	= ctx->get_mappings ()->lookup_location (hir_type->get_ref ());
+	= ctx->get_mappings ().lookup_location (hir_type->get_ref ());
       results.push_back (
 	Backend::typed_identifier ("_", ret, return_type_locus));
     }
@@ -214,7 +214,7 @@ TyTyResolveCompile::visit (const TyTy::FnType &type)
 
       auto compiled_param = Backend::typed_identifier (
 	param_pair.first->as_string (), compiled_param_type,
-	ctx->get_mappings ()->lookup_location (param_tyty->get_ref ()));
+	ctx->get_mappings ().lookup_location (param_tyty->get_ref ()));
 
       parameters.push_back (compiled_param);
     }
@@ -263,7 +263,7 @@ TyTyResolveCompile::visit (const TyTy::ADTType &type)
 	    = TyTyResolveCompile::compile (ctx, field->get_field_type ());
 
 	  Backend::typed_identifier f (field->get_name (), compiled_field_ty,
-				       ctx->get_mappings ()->lookup_location (
+				       ctx->get_mappings ().lookup_location (
 					 type.get_ty_ref ()));
 	  fields.push_back (std::move (f));
 	}
@@ -307,7 +307,7 @@ TyTyResolveCompile::visit (const TyTy::ADTType &type)
 	  tree enumeral_type
 	    = TyTyResolveCompile::get_implicit_enumeral_node_type (ctx);
 	  Backend::typed_identifier f (RUST_ENUM_DISR_FIELD_NAME, enumeral_type,
-				       ctx->get_mappings ()->lookup_location (
+				       ctx->get_mappings ().lookup_location (
 					 variant->get_id ()));
 	  fields.push_back (std::move (f));
 
@@ -326,7 +326,7 @@ TyTyResolveCompile::visit (const TyTy::ADTType &type)
 
 	      Backend::typed_identifier f (
 		field_name, compiled_field_ty,
-		ctx->get_mappings ()->lookup_location (type.get_ty_ref ()));
+		ctx->get_mappings ().lookup_location (type.get_ty_ref ()));
 	      fields.push_back (std::move (f));
 	    }
 
@@ -353,7 +353,7 @@ TyTyResolveCompile::visit (const TyTy::ADTType &type)
 	  std::string implicit_variant_name = variant->get_identifier ();
 
 	  Backend::typed_identifier f (implicit_variant_name, variant_record,
-				       ctx->get_mappings ()->lookup_location (
+				       ctx->get_mappings ().lookup_location (
 					 type.get_ty_ref ()));
 	  enum_fields.push_back (std::move (f));
 	}
@@ -411,7 +411,7 @@ TyTyResolveCompile::visit (const TyTy::TupleType &type)
       // approach makes it simpler to use a C-only debugger, or
       // GDB's C mode, when debugging Rust.
       Backend::typed_identifier f ("__" + std::to_string (i), compiled_field_ty,
-				   ctx->get_mappings ()->lookup_location (
+				   ctx->get_mappings ().lookup_location (
 				     type.get_ty_ref ()));
       fields.push_back (std::move (f));
     }
@@ -714,14 +714,14 @@ TyTyResolveCompile::create_dyn_obj_record (const TyTy::DynamicObjectType &type)
   tree uintptr_ty = build_pointer_type (uint);
 
   Backend::typed_identifier f ("pointer", uintptr_ty,
-			       ctx->get_mappings ()->lookup_location (
+			       ctx->get_mappings ().lookup_location (
 				 type.get_ty_ref ()));
   fields.push_back (std::move (f));
 
   tree vtable_size = build_int_cst (size_type_node, items.size ());
   tree vtable_type = Backend::array_type (uintptr_ty, vtable_size);
   Backend::typed_identifier vtf ("vtable", vtable_type,
-				 ctx->get_mappings ()->lookup_location (
+				 ctx->get_mappings ().lookup_location (
 				   type.get_ty_ref ()));
   fields.push_back (std::move (vtf));
 
diff --git a/gcc/rust/backend/rust-compile.cc b/gcc/rust/backend/rust-compile.cc
index 47a6dad..20190c3 100644
--- a/gcc/rust/backend/rust-compile.cc
+++ b/gcc/rust/backend/rust-compile.cc
@@ -189,7 +189,7 @@ HIRCompileBase::coerce_to_dyn_object (tree compiled_ref,
 				      location_t locus)
 {
   // DST's get wrapped in a pseudo reference that doesnt exist...
-  const TyTy::ReferenceType r (ctx->get_mappings ()->get_next_hir_id (),
+  const TyTy::ReferenceType r (ctx->get_mappings ().get_next_hir_id (),
 			       TyTy::TyVar (ty->get_ref ()), Mutability::Imm);
 
   tree dynamic_object = TyTyResolveCompile::compile (ctx, &r);
diff --git a/gcc/rust/backend/rust-mangle-v0.cc b/gcc/rust/backend/rust-mangle-v0.cc
index c8582b5..0c85d42 100644
--- a/gcc/rust/backend/rust-mangle-v0.cc
+++ b/gcc/rust/backend/rust-mangle-v0.cc
@@ -369,13 +369,13 @@ static std::string
 v0_path (Rust::Compile::Context *ctx, const TyTy::BaseType *ty,
 	 const Resolver::CanonicalPath &cpath)
 {
-  auto mappings = Analysis::Mappings::get ();
+  auto &mappings = Analysis::Mappings::get ();
 
   V0Path v0path = {};
 
   cpath.iterate_segs ([&] (const Resolver::CanonicalPath &seg) {
     HirId hir_id;
-    bool ok = mappings->lookup_node_to_hir (seg.get_node_id (), &hir_id);
+    bool ok = mappings.lookup_node_to_hir (seg.get_node_id (), &hir_id);
     if (!ok)
       {
 	// FIXME: generic arg in canonical path? (e.g. <i32> in crate::S<i32>)
@@ -384,10 +384,10 @@ v0_path (Rust::Compile::Context *ctx, const TyTy::BaseType *ty,
 
     HirId parent_impl_id = UNKNOWN_HIRID;
     HIR::ImplItem *impl_item
-      = mappings->lookup_hir_implitem (hir_id, &parent_impl_id);
-    HIR::TraitItem *trait_item = mappings->lookup_hir_trait_item (hir_id);
-    HIR::Item *item = mappings->lookup_hir_item (hir_id);
-    HIR::Expr *expr = mappings->lookup_hir_expr (hir_id);
+      = mappings.lookup_hir_implitem (hir_id, &parent_impl_id);
+    HIR::TraitItem *trait_item = mappings.lookup_hir_trait_item (hir_id);
+    HIR::Item *item = mappings.lookup_hir_item (hir_id);
+    HIR::Expr *expr = mappings.lookup_hir_expr (hir_id);
 
     if (impl_item != nullptr)
       {
@@ -490,7 +490,7 @@ v0_mangle_item (Rust::Compile::Context *ctx, const TyTy::BaseType *ty,
   rust_debug ("Start mangling: %s", path.get ().c_str ());
 
   // TODO: get Instanciating CrateNum
-  // auto mappings = Analysis::Mappings::get ();
+  // auto &mappings = Analysis::Mappings::get ();
   // std::string crate_name;
   // bool ok = mappings->get_crate_name (path.get_crate_num (), crate_name);
   // rust_assert (ok);