Introduce scopes to keep track of catch blocks at compile time.

src/rewriter.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 200 matching lines @@
 #undef DEF_VISIT
 
 
 // Assumes code has been parsed and scopes have been analyzed.  Mutates the
 // AST, so the AST should not continue to be used in the case of failure.
 bool Rewriter::Rewrite(CompilationInfo* info) {
   FunctionLiteral* function = info->function();
   ASSERT(function != NULL);
   Scope* scope = function->scope();
   ASSERT(scope != NULL);
-  if (scope->is_function_scope()) return true;
+  if (!scope->is_global_scope() && !scope->is_eval_scope()) return true;
 
   ZoneList<Statement*>* body = function->body();
   if (!body->is_empty()) {
     Variable* result = scope->NewTemporary(
         info->isolate()->factory()->result_symbol());
     Processor processor(result);
     processor.Process(body);
     if (processor.HasStackOverflow()) return false;
 
     if (processor.result_assigned()) {
       VariableProxy* result_proxy = new VariableProxy(result);
       body->Add(new ReturnStatement(result_proxy));
     }
   }
 
   return true;
 }
 
 
 } }  // namespace v8::internal