The thread plan destructors may call Thread virtual methods.  That means they have to get cleaned up in the derived class's destructor.  Make sure that happens.

git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@119675 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Target/ThreadPlanBase.cpp b/source/Target/ThreadPlanBase.cpp
index 55ef2f7..eceb383 100644
--- a/source/Target/ThreadPlanBase.cpp
+++ b/source/Target/ThreadPlanBase.cpp
@@ -36,7 +36,14 @@
     ThreadPlan(ThreadPlan::eKindBase, "base plan", thread, eVoteYes, eVoteNoOpinion)
 {
     // Set the tracer to a default tracer.
+    // FIXME: need to add a thread settings variable to pix various tracers...
+#define THREAD_PLAN_USE_ASSEMBLY_TRACER 1
+
+#ifdef THREAD_PLAN_USE_ASSEMBLY_TRACER
+    ThreadPlanTracerSP new_tracer_sp (new ThreadPlanAssemblyTracer (m_thread));
+#else
     ThreadPlanTracerSP new_tracer_sp (new ThreadPlanTracer (m_thread));
+#endif
     new_tracer_sp->EnableTracing (m_thread.GetTraceEnabledState());
     SetThreadPlanTracer(new_tracer_sp);
 }