From fc84f62a65e638ea2231492028fd60704957b8a9 Mon Sep 17 00:00:00 2001
From: Joshua Warner <joshua.warner@readytalk.com>
Date: Fri, 22 Feb 2013 16:33:07 -0700
Subject: [PATCH] prevent garbage collection as vm shuts down

---
 src/machine.cpp | 5 +++--
 src/machine.h   | 1 +
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/machine.cpp b/src/machine.cpp
index c070391f2a..b65d57360e 100644
--- a/src/machine.cpp
+++ b/src/machine.cpp
@@ -2885,7 +2885,8 @@ doCollect(Thread* t, Heap::CollectionType type)
   }
 
   if ((root(t, Machine::ObjectsToFinalize) or root(t, Machine::ObjectsToClean))
-      and m->finalizeThread == 0)
+      and m->finalizeThread == 0
+      and t->state != Thread::ExitState)
   {
     m->finalizeThread = m->processor->makeThread
       (m, root(t, Machine::FinalizerThread), m->rootThread);
@@ -3452,7 +3453,7 @@ enter(Thread* t, Thread::State s)
     switch (t->state) {
     case Thread::ExclusiveState: {
       assert(t, t->m->exclusive == t);
-      t->m->exclusive = 0;
+      // exit state should also be exclusive, so don't set exclusive = 0
 
       t->m->stateLock->notifyAll(t->systemThread);
     } break;
diff --git a/src/machine.h b/src/machine.h
index f00f5a3328..982b4fb086 100644
--- a/src/machine.h
+++ b/src/machine.h
@@ -1972,6 +1972,7 @@ addThread(Thread* t, Thread* p)
   ACQUIRE_RAW(t, t->m->stateLock);
 
   assert(t, p->state == Thread::NoState);
+  expect(t, t->state == Thread::ActiveState || t->state == Thread::ExclusiveState);
 
   p->state = Thread::IdleState;
   ++ t->m->threadCount;