8 files changed, 21 insertions, 26 deletions

diff --git a/gcc/rust/backend/rust-compile-expr.cc b/gcc/rust/backend/rust-compile-expr.cc
index ab560e8..a592e35 100644
--- a/gcc/rust/backend/rust-compile-expr.cc
+++ b/gcc/rust/backend/rust-compile-expr.cc
@@ -205,7 +205,7 @@ CompileExpr::visit (HIR::MatchExpr &expr)
 	expr.get_scrutinee_expr ()->get_mappings ().get_hirid (),
 	&scrutinee_expr_tyty))
     {
-      translated = ctx->get_backend ()->error_expression ();
+      translated = error_mark_node;
       return;
     }
 
@@ -221,7 +221,7 @@ CompileExpr::visit (HIR::MatchExpr &expr)
   if (!ctx->get_tyctx ()->lookup_type (expr.get_mappings ().get_hirid (),
 				       &expr_tyty))
     {
-      translated = ctx->get_backend ()->error_expression ();
+      translated = error_mark_node;
       return;
     }
 
@@ -644,7 +644,7 @@ CompileExpr::compile_dyn_dispatch_call (const TyTy::DynamicObjectType *dyn,
     }
 
   if (ref == nullptr)
-    return ctx->get_backend ()->error_expression ();
+    return error_mark_node;
 
   // get any indirection sorted out
   if (receiver->get_kind () == TyTy::TypeKind::REF)
diff --git a/gcc/rust/backend/rust-compile-expr.h b/gcc/rust/backend/rust-compile-expr.h
index 592d280..2fee3be 100644
--- a/gcc/rust/backend/rust-compile-expr.h
+++ b/gcc/rust/backend/rust-compile-expr.h
@@ -383,8 +383,8 @@ public:
 	ctx->add_statement (ret_var_stmt);
       }
 
-    auto code_block = CompileBlock::compile (&expr, ctx, tmp);
-    auto block_stmt = ctx->get_backend ()->block_statement (code_block);
+    auto block_stmt = CompileBlock::compile (&expr, ctx, tmp);
+    rust_assert (TREE_CODE (block_stmt) == BIND_EXPR);
     ctx->add_statement (block_stmt);
 
     if (tmp != NULL)
@@ -680,9 +680,9 @@ public:
       = ctx->get_backend ()->expression_statement (fnctx.fndecl, exit_expr);
     ctx->add_statement (break_stmt);
 
-    tree code_block
+    tree code_block_stmt
       = CompileBlock::compile (expr.get_loop_block ().get (), ctx, nullptr);
-    tree code_block_stmt = ctx->get_backend ()->block_statement (code_block);
+    rust_assert (TREE_CODE (code_block_stmt) == BIND_EXPR);
     ctx->add_statement (code_block_stmt);
 
     ctx->pop_loop_begin_label ();
diff --git a/gcc/rust/backend/rust-compile-implitem.h b/gcc/rust/backend/rust-compile-implitem.h
index 60b7246..4d49c0b 100644
--- a/gcc/rust/backend/rust-compile-implitem.h
+++ b/gcc/rust/backend/rust-compile-implitem.h
@@ -40,8 +40,7 @@ public:
     CompileInherentImplItem compiler (ctx, concrete, ref_locus);
     item->accept_vis (compiler);
 
-    if (is_query_mode
-	&& ctx->get_backend ()->is_error_expression (compiler.reference))
+    if (is_query_mode && compiler.reference == error_mark_node)
       rust_internal_error_at (ref_locus, "failed to compile impl item: %s",
 			      item->as_string ().c_str ());
 
@@ -67,8 +66,7 @@ public:
     CompileTraitItem compiler (ctx, concrete, ref_locus);
     item->accept_vis (compiler);
 
-    if (is_query_mode
-	&& ctx->get_backend ()->is_error_expression (compiler.reference))
+    if (is_query_mode && compiler.reference == error_mark_node)
       rust_internal_error_at (ref_locus, "failed to compile trait item: %s",
 			      item->as_string ().c_str ());
 
@@ -81,8 +79,7 @@ public:
 
 private:
   CompileTraitItem (Context *ctx, TyTy::BaseType *concrete, Location ref_locus)
-    : HIRCompileBase (ctx), concrete (concrete),
-      reference (ctx->get_backend ()->error_expression ()),
+    : HIRCompileBase (ctx), concrete (concrete), reference (error_mark_node),
       ref_locus (ref_locus)
   {}
 
diff --git a/gcc/rust/backend/rust-compile-intrinsic.cc b/gcc/rust/backend/rust-compile-intrinsic.cc
index 69626a9..8c5b073 100644
--- a/gcc/rust/backend/rust-compile-intrinsic.cc
+++ b/gcc/rust/backend/rust-compile-intrinsic.cc
@@ -85,7 +85,7 @@ Intrinsics::compile (TyTy::FnType *fntype)
   Location locus = ctx->get_mappings ()->lookup_location (fntype->get_ref ());
   rust_error_at (locus, "unknown builtin");
 
-  return ctx->get_backend ()->error_function ();
+  return error_mark_node;
 }
 
 } // namespace Compile
diff --git a/gcc/rust/backend/rust-compile-item.h b/gcc/rust/backend/rust-compile-item.h
index 71f259f..897fe85 100644
--- a/gcc/rust/backend/rust-compile-item.h
+++ b/gcc/rust/backend/rust-compile-item.h
@@ -38,8 +38,7 @@ public:
     CompileItem compiler (ctx, concrete, ref_locus);
     item->accept_vis (compiler);
 
-    if (is_query_mode
-	&& ctx->get_backend ()->is_error_expression (compiler.reference))
+    if (is_query_mode && compiler.reference == error_mark_node)
       rust_internal_error_at (ref_locus, "failed to compile item: %s",
 			      item->as_string ().c_str ());
 
diff --git a/gcc/rust/backend/rust-compile-resolve-path.cc b/gcc/rust/backend/rust-compile-resolve-path.cc
index 2ef1232..e41ee7f 100644
--- a/gcc/rust/backend/rust-compile-resolve-path.cc
+++ b/gcc/rust/backend/rust-compile-resolve-path.cc
@@ -58,7 +58,7 @@ ResolvePathRef::resolve (const HIR::PathIdentSegment &final_segment,
       if (!ctx->get_resolver ()->lookup_definition (ref_node_id, &def))
 	{
 	  rust_error_at (expr_locus, "unknown reference for resolved name");
-	  return ctx->get_backend ()->error_expression ();
+	  return error_mark_node;
 	}
       ref_node_id = def.parent;
     }
@@ -69,22 +69,22 @@ ResolvePathRef::resolve (const HIR::PathIdentSegment &final_segment,
     {
       // it might be an enum data-less enum variant
       if (lookup->get_kind () != TyTy::TypeKind::ADT)
-	return ctx->get_backend ()->error_expression ();
+	return error_mark_node;
 
       TyTy::ADTType *adt = static_cast<TyTy::ADTType *> (lookup);
       if (!adt->is_enum ())
-	return ctx->get_backend ()->error_expression ();
+	return error_mark_node;
 
       HirId variant_id;
       if (!ctx->get_tyctx ()->lookup_variant_definition (mappings.get_hirid (),
 							 &variant_id))
-	return ctx->get_backend ()->error_expression ();
+	return error_mark_node;
 
       int union_disriminator = -1;
       TyTy::VariantDef *variant = nullptr;
       if (!adt->lookup_variant_by_id (variant_id, &variant,
 				      &union_disriminator))
-	return ctx->get_backend ()->error_expression ();
+	return error_mark_node;
 
       // this can only be for discriminant variants the others are built up
       // using call-expr or struct-init
@@ -111,7 +111,7 @@ ResolvePathRef::resolve (const HIR::PathIdentSegment &final_segment,
 						 ref_node_id, &ref))
     {
       rust_error_at (expr_locus, "reverse call path lookup failure");
-      return ctx->get_backend ()->error_expression ();
+      return error_mark_node;
     }
 
   // might be a constant
@@ -274,7 +274,7 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 	}
     }
 
-  return ctx->get_backend ()->error_expression ();
+  return error_mark_node;
 }
 
 } // namespace Compile
diff --git a/gcc/rust/backend/rust-compile-resolve-path.h b/gcc/rust/backend/rust-compile-resolve-path.h
index b4161cb..9c9d7c5 100644
--- a/gcc/rust/backend/rust-compile-resolve-path.h
+++ b/gcc/rust/backend/rust-compile-resolve-path.h
@@ -50,7 +50,7 @@ public:
 
 private:
   ResolvePathRef (Context *ctx)
-    : HIRCompileBase (ctx), resolved (ctx->get_backend ()->error_expression ())
+    : HIRCompileBase (ctx), resolved (error_mark_node)
   {}
 
   tree resolve (const HIR::PathIdentSegment &final_segment,
diff --git a/gcc/rust/backend/rust-compile-var-decl.h b/gcc/rust/backend/rust-compile-var-decl.h
index 7bc37eb..c431edd 100644
--- a/gcc/rust/backend/rust-compile-var-decl.h
+++ b/gcc/rust/backend/rust-compile-var-decl.h
@@ -72,8 +72,7 @@ public:
 
 private:
   CompileVarDecl (Context *ctx, tree fndecl)
-    : HIRCompileBase (ctx), fndecl (fndecl),
-      translated_type (ctx->get_backend ()->error_type ()),
+    : HIRCompileBase (ctx), fndecl (fndecl), translated_type (error_mark_node),
       compiled_variable (ctx->get_backend ()->error_variable ())
   {}