Do not put failures in handles....

src/jsregexp.cc

 // Copyright 2006-2008 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 364 matching lines @@
                           &code);
 
   if (code == NULL) {
     // Throw an exception.
     Handle<JSArray> array = Factory::NewJSArray(2);
     SetElement(array, 0, pattern);
     SetElement(array, 1, Factory::NewStringFromUtf8(CStrVector(
         (error_message == NULL) ? "Unknown regexp error" : error_message)));
     Handle<Object> regexp_err =
         Factory::NewSyntaxError("malformed_regexp", array);
-    return Handle<Object>(Top::Throw(*regexp_err));
+    Top::Throw(*regexp_err);
+    return Handle<Object>();
   }
 
   // Convert the return address to a ByteArray pointer.
   Handle<ByteArray> internal(
       ByteArray::FromDataStartAddress(reinterpret_cast<Address>(code)));
 
   Handle<FixedArray> value = Factory::NewFixedArray(2);
   value->set(CAPTURE_INDEX, Smi::FromInt(number_of_captures));
   value->set(INTERNAL_INDEX, *internal);
   Factory::SetRegExpData(re, JSRegExp::JSCRE, pattern, flags, value);
@@ skipping 169 matching lines @@
   return Smi::cast(value->get(CAPTURE_INDEX))->value();
 }
 
 
 ByteArray* RegExpImpl::JsreInternal(Handle<JSRegExp> re) {
   FixedArray* value = FixedArray::cast(re->DataAt(JSRegExp::kJscreDataIndex));
   return ByteArray::cast(value->get(INTERNAL_INDEX));
 }
 
 }}  // namespace v8::internal