Fix crash in d8 when external array ctor hits stack overflow

BUG=100859
TEST=mjsunit/regress/regress-crbug-100859

Review URL: http://codereview.chromium.org/8898021

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10242 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/d8.cc

@@ -296,14 +296,26 @@ Handle<Value> Shell::CreateExternalArray(const Arguments& args,
   ASSERT(kMaxLength == i::ExternalArray::kMaxLength);
 #endif  // V8_SHARED
   size_t length = 0;
+  TryCatch try_catch;
   if (args[0]->IsUint32()) {
     length = args[0]->Uint32Value();
   } else {
     Local<Number> number = args[0]->ToNumber();
-    if (number.IsEmpty() || !number->IsNumber()) {
-      return ThrowException(String::New("Array length must be a number."));
+    if (number.IsEmpty()) {
+      ASSERT(try_catch.HasCaught());
+      return try_catch.Exception();
+    }
+    ASSERT(number->IsNumber());
+    Local<Int32> int32 = number->ToInt32();
+    if (int32.IsEmpty()) {
+      if (try_catch.HasCaught()) {
+        return try_catch.Exception();
+      }
+    }
+    int32_t raw_length = int32->Int32Value();
+    if (try_catch.HasCaught()) {
+      return try_catch.Exception();
     }
-    int32_t raw_length = number->ToInt32()->Int32Value();
     if (raw_length < 0) {
       return ThrowException(String::New("Array length must not be negative."));
     }

test/mjsunit/regress/regress-crbug-100859.js

+// 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
+//       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.
+
+// This used to trigger a crash because of an unhandled stack overflow.
+function setx() {
+  setx(typeof new Uint16Array('x') === 'object');
+}
+var exception = false;
+try {
+  setx();
+} catch (ex) {
+  assertTrue(ex instanceof RangeError);
+  exception = true;
+}
+assertTrue(exception);