From 10eea33164e9f7c08b25d45b1157d213aca908ec Mon Sep 17 00:00:00 2001
From: Brian Norris <banorris@uci.edu>
Date: Thu, 19 Apr 2012 00:10:17 -0700
Subject: [PATCH] tree: don't use 'NULL' for a thread ID

---
 tree.cc | 2 +-
 tree.h  | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/tree.cc b/tree.cc
index f42202ec..c52c1840 100644
--- a/tree.cc
+++ b/tree.cc
@@ -43,7 +43,7 @@ int TreeNode::setBacktrack(tree_t id)
 tree_t TreeNode::getNextBacktrack()
 {
 	if (backtrack.empty())
-		return NULL;
+		return TREE_T_NONE;
 	return *backtrack.begin();
 }
 
diff --git a/tree.h b/tree.h
index 766aacd9..6d37038e 100644
--- a/tree.h
+++ b/tree.h
@@ -3,6 +3,7 @@
 #include "threads.h"
 
 typedef thread_id_t tree_t;
+#define TREE_T_NONE	-1
 
 /*
  * An n-ary tree
-- 
2.34.1