Fix missing exception check in typed array constructor.

The typed array constructor might fail if the first argument is an
object with a length property. Accessing the property can cause an
exception to be thrown and an explicit check needs to be performed.

R=verwaest@chromium.org
BUG=chromium:168545
TEST=mjsunit/regress/regress-crbug-168545.js

Review URL: https://codereview.chromium.org/11777014

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13325 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/d8.cc

@@ -532,8 +532,9 @@ Handle<Value> Shell::CreateExternalArray(const Arguments& args,
     if (args[0]->IsObject() &&
         args[0]->ToObject()->Has(Symbols::length(isolate))) {
       // Construct from array.
-      length = convertToUint(
-          args[0]->ToObject()->Get(Symbols::length(isolate)), &try_catch);
+      Local<Value> value = args[0]->ToObject()->Get(Symbols::length(isolate));
+      if (try_catch.HasCaught()) return try_catch.ReThrow();
+      length = convertToUint(value, &try_catch);
       if (try_catch.HasCaught()) return try_catch.ReThrow();
       init_from_array = true;
     } else {

test/mjsunit/regress/regress-crbug-168545.js

+// Copyright 2013 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
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+var o = {};
+Object.defineProperty(o, "length", { get: function() { throw "bail"; }});
+assertThrows("new Int16Array(o);");