- Ensure positive keys for private mangling.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 9293 matching lines @@
     if (lib_key == key) {
       return true;
     }
   }
   return false;
 }
 
 
 void Library::AllocatePrivateKey() const {
   const String& url = String::Handle(this->url());
-  intptr_t key_value = url.Hash();
-  while (Library::IsKeyUsed(key_value)) {
-    key_value++;
+  intptr_t key_value = url.Hash() & kIntptrMax;
+  while ((key_value == 0) || Library::IsKeyUsed(key_value)) {
+    key_value = (key_value + 1) & kIntptrMax;
   }
+  ASSERT(key_value > 0);
   char private_key[32];
   OS::SNPrint(private_key, sizeof(private_key),
               "%c%" Pd "", kPrivateKeySeparator, key_value);
   StorePointer(&raw_ptr()->private_key_, String::New(private_key, Heap::kOld));
 }
 
 
 const String& Library::PrivateCoreLibName(const String& member) {
   const Library& core_lib = Library::Handle(Library::CoreLibrary());
   const String& private_name = String::ZoneHandle(core_lib.PrivateName(member));
@@ skipping 9690 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart