Do not rely on uniquiness of pthread_t

src/api.cc

 // Copyright 2010 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 4607 matching lines @@
   ASSERT(max_size >= kMinimumSizeForLogLinesBuffer);
   return LOGGER->GetLogLines(from_pos, dest_buf, max_size);
 #endif
   return 0;
 }
 
 
 int V8::GetCurrentThreadId() {
   i::Isolate* isolate = i::Isolate::Current();
   EnsureInitializedForIsolate(isolate, "V8::GetCurrentThreadId()");
-  return isolate->thread_id();
+  return isolate->thread_id().ToInteger();
 }
 
 
 void V8::TerminateExecution(int thread_id) {
   i::Isolate* isolate = i::Isolate::Current();
   if (!isolate->IsInitialized()) return;
   API_ENTRY_CHECK("V8::TerminateExecution()");
   // If the thread_id identifies the current thread just terminate
   // execution right away.  Otherwise, ask the thread manager to
   // terminate the thread with the given id if any.
-  if (thread_id == isolate->thread_id()) {
+  i::ThreadId internal_tid = i::ThreadId::FromInteger(thread_id);
+  if (isolate->thread_id().Equals(internal_tid)) {
     isolate->stack_guard()->TerminateExecution();
   } else {
-    isolate->thread_manager()->TerminateExecution(thread_id);
+    isolate->thread_manager()->TerminateExecution(internal_tid);
   }
 }
 
 
 void V8::TerminateExecution(Isolate* isolate) {
   // If no isolate is supplied, use the default isolate.
   if (isolate != NULL) {
     reinterpret_cast<i::Isolate*>(isolate)->stack_guard()->TerminateExecution();
   } else {
     i::Isolate::GetDefaultIsolateStackGuard()->TerminateExecution();
@@ skipping 1019 matching lines @@
 
 
 char* HandleScopeImplementer::Iterate(ObjectVisitor* v, char* storage) {
   HandleScopeImplementer* scope_implementer =
       reinterpret_cast<HandleScopeImplementer*>(storage);
   scope_implementer->IterateThis(v);
   return storage + ArchiveSpacePerThread();
 }
 
 } }  // namespace v8::internal