fix -Wunused-but-set-variable for gcc-4.6 on x64

src/debug.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 754 matching lines @@
     ASSERT(isolate->has_pending_exception());
     isolate->clear_pending_exception();
     return false;
   }
 
   // Execute the shared function in the debugger context.
   Handle<Context> context = isolate->global_context();
   bool caught_exception = false;
   Handle<JSFunction> function =
       factory->NewFunctionFromSharedFunctionInfo(function_info, context);
-  Handle<Object> result =
-      Execution::TryCall(function, Handle<Object>(context->global()),
-                         0, NULL, &caught_exception);
+
+  Execution::TryCall(function, Handle<Object>(context->global()),
+                     0, NULL, &caught_exception);
 
   // Check for caught exceptions.
   if (caught_exception) {
     Handle<Object> message = MessageHandler::MakeMessageObject(
         "error_loading_debugger", NULL, Vector<Handle<Object> >::empty(),
         Handle<String>(), Handle<JSArray>());
     MessageHandler::ReportMessage(Isolate::Current(), NULL, message);
     return false;
   }
 
@@ skipping 1091 matching lines @@
   HandleScope scope(isolate_);
   ASSERT(isolate_->context() == *Debug::debug_context());
 
   // Clear the mirror cache.
   Handle<String> function_name =
       isolate_->factory()->LookupSymbol(CStrVector("ClearMirrorCache"));
   Handle<Object> fun(Isolate::Current()->global()->GetPropertyNoExceptionThrown(
       *function_name));
   ASSERT(fun->IsJSFunction());
   bool caught_exception;
-  Handle<Object> js_object = Execution::TryCall(
-      Handle<JSFunction>::cast(fun),
+  Execution::TryCall(Handle<JSFunction>::cast(fun),
       Handle<JSObject>(Debug::debug_context()->global()),
       0, NULL, &caught_exception);
 }
 
 
 void Debug::CreateScriptCache() {
   Heap* heap = isolate_->heap();
   HandleScope scope(isolate_);
 
   // Perform two GCs to get rid of all unreferenced scripts. The first GC gets
@@ skipping 344 matching lines @@
   ASSERT(update_script_break_points->IsJSFunction());
 
   // Wrap the script object in a proper JS object before passing it
   // to JavaScript.
   Handle<JSValue> wrapper = GetScriptWrapper(script);
 
   // Call UpdateScriptBreakPoints expect no exceptions.
   bool caught_exception = false;
   const int argc = 1;
   Object** argv[argc] = { reinterpret_cast<Object**>(wrapper.location()) };
-  Handle<Object> result = Execution::TryCall(
-      Handle<JSFunction>::cast(update_script_break_points),
+  Execution::TryCall(Handle<JSFunction>::cast(update_script_break_points),
       Isolate::Current()->js_builtins_object(), argc, argv,
       &caught_exception);
   if (caught_exception) {
     return;
   }
   // Bail out based on state or if there is no listener for this event
   if (in_debugger && (after_compile_flags & SEND_WHEN_DEBUGGING) == 0) return;
   if (!Debugger::EventActive(v8::AfterCompile)) return;
 
   // Create the compile state object.
@@ skipping 656 matching lines @@
     return v8::Utils::ToLocal(response_json_);
   }
 }
 
 
 v8::Handle<v8::Context> MessageImpl::GetEventContext() const {
   Isolate* isolate = Isolate::Current();
   v8::Handle<v8::Context> context = GetDebugEventContext(isolate);
   // Isolate::context() may be NULL when "script collected" event occures.
   ASSERT(!context.IsEmpty() || event_ == v8::ScriptCollected);
-  return GetDebugEventContext(isolate);
+  return context;
 }
 
 
 v8::Debug::ClientData* MessageImpl::GetClientData() const {
   return client_data_;
 }
 
 
 EventDetailsImpl::EventDetailsImpl(DebugEvent event,
                                    Handle<JSObject> exec_state,
@@ skipping 185 matching lines @@
     {
       Locker locker;
       Isolate::Current()->debugger()->CallMessageDispatchHandler();
     }
   }
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal