Use ExitProcess on Windows.

runtime/vm/thread.cc

 // Copyright (c) 2015, 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/thread.h"
 
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
 #include "vm/lockers.h"
 #include "vm/log.h"
@@ skipping 107 matching lines @@
 }
 
 
 static void DeleteThread(void* thread) {
   delete reinterpret_cast<Thread*>(thread);
 }
 
 
 void Thread::Shutdown() {
   if (thread_list_lock_ != NULL) {
+    Thread* thread = Current();
+    ASSERT(thread != NULL);
+    delete thread;
+    thread = NULL;
+    SetCurrent(NULL);
+    OSThread::DeleteThreadLocal(thread_key_);

[Cutch, 2015/10/28 20:33:15]

Can we move this TLS cleanup below the ASSERT. 

Once we know we have no more threads we don't ever care about the TLS
destructor.

[zra, 2015/10/28 21:40:04]

Moved.
I was hitting a crash where ~Thread() was running called from DeleteThread()
after Shutdown(), so I'm a bit paranoid about cleaning up the TLS now.

+    thread_key_ = OSThread::kUnsetThreadLocalKey;
+
+    // Check that there are no more threads, then delete the lock.
+    {
+      MutexLocker ml(thread_list_lock_);
+      ASSERT(thread_list_head_ == NULL);
+    }
     delete thread_list_lock_;
     thread_list_lock_ = NULL;
   }
 }
 
 
 Thread::~Thread() {
   // We should cleanly exit any isolate before destruction.
   ASSERT(isolate_ == NULL);
   // Clear |this| from all isolate's thread registry.
@@ skipping 428 matching lines @@
 Thread* ThreadIterator::Next() {
   ASSERT(Thread::thread_list_lock_ != NULL);
   ASSERT(Thread::thread_list_lock_->IsOwnedByCurrentThread());
   Thread* current = next_;
   next_ = next_->thread_list_next_;
   return current;
 }
 
 
 }  // namespace dart