Fix zone in which temp-zone parsed data is allocated for the function scope on the boundary.

src/parsing/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/parsing/parser.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/ast/ast-expression-rewriter.h"
@@ skipping 2608 matching lines @@
   bool use_temp_zone =
       (FLAG_lazy_inner_functions
            ? can_preparse
            : (is_lazy_top_level_function ||
               (allow_lazy_ && function_type == FunctionLiteral::kDeclaration &&
                eager_compile_hint == FunctionLiteral::kShouldLazyCompile))) &&
       !(FLAG_validate_asm && scope()->IsAsmModule());
   bool is_lazy_inner_function =
       use_temp_zone && FLAG_lazy_inner_functions && !is_lazy_top_level_function;
 
-  // This Scope lives in the main zone. We'll migrate data into that zone later.
-  DeclarationScope* scope = NewFunctionScope(kind);
-  SetLanguageMode(scope, language_mode);
-#ifdef DEBUG
-  scope->SetScopeName(function_name);
-#endif
-
   ZoneList<Statement*>* body = nullptr;
   int materialized_literal_count = -1;
   int expected_property_count = -1;
   bool should_be_used_once_hint = false;
   int num_parameters = -1;
   int function_length = -1;
   bool has_duplicate_parameters = false;
 
-  Expect(Token::LPAREN, CHECK_OK);
-  scope->set_start_position(scanner()->location().beg_pos);
+  Zone* outer_zone = zone();
+  DeclarationScope* scope;
 
   {
     // Temporary zones can nest. When we migrate free variables (see below), we
     // need to recreate them in the previous Zone.
     AstNodeFactory previous_zone_ast_node_factory(ast_value_factory());
     previous_zone_ast_node_factory.set_zone(zone());
 
     // Open a new zone scope, which sets our AstNodeFactory to allocate in the
     // new temporary zone if the preconditions are satisfied, and ensures that
     // the previous zone is always restored after parsing the body. To be able
     // to do scope analysis correctly after full parsing, we migrate needed
     // information when the function is parsed.
     Zone temp_zone(zone()->allocator(), ZONE_NAME);
     DiscardableZoneScope zone_scope(this, &temp_zone, use_temp_zone);
+
+    // This Scope lives in the main zone. We'll migrate data into that zone
+    // later.
+    scope = NewFunctionScope(kind, outer_zone);
+    SetLanguageMode(scope, language_mode);
 #ifdef DEBUG
+    scope->SetScopeName(function_name);
     if (use_temp_zone) scope->set_needs_migration();
 #endif
 
+    Expect(Token::LPAREN, CHECK_OK);
+    scope->set_start_position(scanner()->location().beg_pos);
+
     // Eager or lazy parse? If is_lazy_top_level_function, we'll parse
     // lazily. We'll call SkipFunction, which may decide to
     // abort lazy parsing if it suspects that wasn't a good idea. If so (in
     // which case the parser is expected to have backtracked), or if we didn't
     // try to lazy parse in the first place, we'll have to parse eagerly.
     if (is_lazy_top_level_function || is_lazy_inner_function) {
       Scanner::BookmarkScope bookmark(scanner());
       bookmark.Set();
       LazyParsingResult result =
           SkipFunction(kind, scope, &num_parameters, &function_length,
@@ skipping 2796 matching lines @@
 
   return final_loop;
 }
 
 #undef CHECK_OK
 #undef CHECK_OK_VOID
 #undef CHECK_FAILED
 
 }  // namespace internal
 }  // namespace v8