Restore message when rethrowing in TryCatch.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 58041309b1a148b9796bf909967a32556518fb1c..78519147f651f9ce21536ccd3a906268cd300dce 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -2074,13 +2074,12 @@ void Script::SetData(v8::Handle<String> data) {
 v8::TryCatch::TryCatch()
     : isolate_(i::Isolate::Current()),
       next_(isolate_->try_catch_handler_address()),
-      exception_(isolate_->heap()->the_hole_value()),
-      message_(i::Smi::FromInt(0)),
       is_verbose_(false),
       can_continue_(true),
       capture_message_(true),
       rethrow_(false),
       has_terminated_(false) {
+  Reset();
   isolate_->RegisterTryCatchHandler(this);
 }
 
@@ -2090,8 +2089,17 @@ v8::TryCatch::~TryCatch() {
   if (rethrow_) {
     v8::HandleScope scope(reinterpret_cast<Isolate*>(isolate_));
     v8::Local<v8::Value> exc = v8::Local<v8::Value>::New(Exception());
+    if (HasCaught() && capture_message_) {
+      // If an exception was caught and rethrow_ is indicated, the saved
+      // message, script, and location need to be restored to Isolate TLS
+      // for reuse.  capture_message_ needs to be disabled so that DoThrow()
+      // does not create a new message.
+      isolate_->thread_local_top()->rethrowing_message_ = true;
+      isolate_->RestorePendingMessageFromTryCatch(this);
+    }
     isolate_->UnregisterTryCatchHandler(this);
     v8::ThrowException(exc);
+    ASSERT(!isolate_->thread_local_top()->rethrowing_message_);
   } else {
     isolate_->UnregisterTryCatchHandler(this);
   }
@@ -2152,8 +2160,9 @@ v8::Local<Value> v8::TryCatch::StackTrace() const {
 
 v8::Local<v8::Message> v8::TryCatch::Message() const {
   ASSERT(isolate_ == i::Isolate::Current());
-  if (HasCaught() && message_ != i::Smi::FromInt(0)) {
-    i::Object* message = reinterpret_cast<i::Object*>(message_);
+  i::Object* message = reinterpret_cast<i::Object*>(message_obj_);
+  ASSERT(message->IsJSMessageObject() || message->IsTheHole());
+  if (HasCaught() && !message->IsTheHole()) {
     return v8::Utils::MessageToLocal(i::Handle<i::Object>(message, isolate_));
   } else {
     return v8::Local<v8::Message>();
@@ -2163,8 +2172,12 @@ v8::Local<v8::Message> v8::TryCatch::Message() const {
 
 void v8::TryCatch::Reset() {
   ASSERT(isolate_ == i::Isolate::Current());
-  exception_ = isolate_->heap()->the_hole_value();
-  message_ = i::Smi::FromInt(0);
+  i::Object* the_hole = isolate_->heap()->the_hole_value();
+  exception_ = the_hole;
+  message_obj_ = the_hole;
+  message_script_ = the_hole;
+  message_start_pos_ = 0;
+  message_end_pos_ = 0;
 }