tree: don't use 'NULL' for a thread ID

diff --git a/tree.cc b/tree.cc
index f42202ec1bfd46f9935805eceafbc8930f4d7aff..c52c184077519e5ccc2d802fd4a98634cdf438c2 100644 (file)
--- 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 766aacd9ff981eb12c0f8f45e0c7b1076b7176f3..6d37038e87a42f0c068d6d1e4107ad2b983c9230 100644 (file)
--- 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