Do not rely on uniquiness of pthread_t

src/runtime.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 10153 matching lines @@
   // Allocate array for result.
   Handle<FixedArray> details =
       isolate->factory()->NewFixedArray(kThreadDetailsSize);
 
   // Thread index 0 is current thread.
   if (index == 0) {
     // Fill the details.
     details->set(kThreadDetailsCurrentThreadIndex,
                  isolate->heap()->true_value());
     details->set(kThreadDetailsThreadIdIndex,
-                 Smi::FromInt(
-                     isolate->thread_manager()->CurrentId()));
+                 Smi::FromInt(ThreadId::Current().ToInteger()));
   } else {
     // Find the thread with the requested index.
     int n = 1;
     ThreadState* thread =
         isolate->thread_manager()->FirstThreadStateInUse();
     while (index != n && thread != NULL) {
       thread = thread->Next();
       n++;
     }
     if (thread == NULL) {
       return isolate->heap()->undefined_value();
     }
 
     // Fill the details.
     details->set(kThreadDetailsCurrentThreadIndex,
                  isolate->heap()->false_value());
-    details->set(kThreadDetailsThreadIdIndex, Smi::FromInt(thread->id()));
+    details->set(kThreadDetailsThreadIdIndex,
+                 Smi::FromInt(thread->id().ToInteger()));
   }
 
   // Convert to JS array and return.
   return *isolate->factory()->NewJSArrayWithElements(details);
 }
 
 
 // Sets the disable break state
 // args[0]: disable break state
 RUNTIME_FUNCTION(MaybeObject*, Runtime_SetDisableBreak) {
@@ skipping 1759 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(false);
   }
 }
 
 
 } }  // namespace v8::internal