Disable lazy parsing inside eval (see bug).

src/ast/scopes.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/ast/scopes.h"
 
 #include <set>
 
 #include "src/accessors.h"
 #include "src/ast/ast.h"
@@ skipping 105 matching lines @@
 }
 
 Scope::Scope(Zone* zone, Scope* outer_scope, ScopeType scope_type)
     : zone_(zone),
       outer_scope_(outer_scope),
       variables_(zone),
       scope_type_(scope_type) {
   DCHECK_NE(SCRIPT_SCOPE, scope_type);
   SetDefaults();
   set_language_mode(outer_scope->language_mode());
   force_context_allocation_ =

[adamk, 2016/12/14 08:00:14]

Another option would be to add an

if (is_eval_scope()) return true;

to Scope::MustAllocateInContext(). I think that would be a little more
idiomatic, though there's likely room for some cleanup here...

-      !is_function_scope() && outer_scope->has_forced_context_allocation();
+      (!is_function_scope() && outer_scope->has_forced_context_allocation()) ||
+      is_eval_scope();
   outer_scope_->AddInnerScope(this);
 }
 
 Scope::Snapshot::Snapshot(Scope* scope)
     : outer_scope_(scope),
       top_inner_scope_(scope->inner_scope_),
       top_unresolved_(scope->unresolved_),
       top_local_(scope->GetClosureScope()->locals_.end()),
       top_decl_(scope->GetClosureScope()->decls_.end()) {}
 
@@ skipping 1965 matching lines @@
   Variable* function =
       is_function_scope() ? AsDeclarationScope()->function_var() : nullptr;
   bool is_function_var_in_context =
       function != nullptr && function->IsContextSlot();
   return num_heap_slots() - Context::MIN_CONTEXT_SLOTS -
          (is_function_var_in_context ? 1 : 0);
 }
 
 }  // namespace internal
 }  // namespace v8