Fix a potential crash in const declaration.

Declaration of const lookup slots would trigger an assertion if there was a
setter somewhere in the prototype chain, and that setter was shadowed by a
non-readonly data property also in the prototype chain.

R=ager@chromium.org
BUG=
TEST=

Review URL: http://codereview.chromium.org/7324048

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8602 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects.cc

@@ -1883,13 +1883,9 @@ void JSObject::LookupCallbackSetterInPrototypes(String* name,
        pt = pt->GetPrototype()) {
     JSObject::cast(pt)->LocalLookupRealNamedProperty(name, result);
     if (result->IsProperty()) {
-      if (result->IsReadOnly()) {
-        result->NotFound();
-        return;
-      }
-      if (result->type() == CALLBACKS) {
-        return;
-      }
+      if (result->type() == CALLBACKS && !result->IsReadOnly()) return;
+      // Found non-callback or read-only callback, stop looking.
+      break;
     }
   }
   result->NotFound();
@@ -2273,10 +2269,10 @@ MUST_USE_RESULT PropertyAttributes JSProxy::GetPropertyAttributeWithHandler(
 
 
 MaybeObject* JSObject::SetPropertyForResult(LookupResult* result,
-                                   String* name,
-                                   Object* value,
-                                   PropertyAttributes attributes,
-                                   StrictModeFlag strict_mode) {
+                                            String* name,
+                                            Object* value,
+                                            PropertyAttributes attributes,
+                                            StrictModeFlag strict_mode) {
   Heap* heap = GetHeap();
   // Make sure that the top context does not change when doing callbacks or
   // interceptor calls.

test/mjsunit/regress/regress-88591.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.
+
+// Regression test for a crash.  A data property in the global object's
+// prototype shadowed by a setter in the global object's prototype's
+// prototype would crash or assert when seen by Runtime_DeclareContextSlot.
+var called = false;
+Object.prototype.__defineSetter__('x', function(x) { called = true; });
+Object.prototype.__defineGetter__('x', function () { return 0; });
+
+this.__proto__ = { x: 1 };
+
+try { fail; } catch (e) { eval('const x = 2'); }
+
+var o = Object.getOwnPropertyDescriptor(this, 'x');
+assertFalse(called);
+assertEquals(2, o.value);
+assertEquals(false, o.writable);