diff --git a/indra/llcommon/lldependencies.h b/indra/llcommon/lldependencies.h
index de214a894363001c0f7fc26a89da85cd135e09c9..db2bbab8b040269e04bec4638b70bea4dd6fa4e4 100644
--- a/indra/llcommon/lldependencies.h
+++ b/indra/llcommon/lldependencies.h
@@ -124,8 +124,8 @@ class LL_COMMON_API LLDependenciesBase
     virtual std::string describe(bool full=true) const;
 
 protected:
-    typedef std::vector< std::pair<int, int> > EdgeList;
-    typedef std::vector<int> VertexList;
+    typedef std::vector< std::pair<std::size_t, std::size_t> > EdgeList;
+    typedef std::vector<std::size_t> VertexList;
     VertexList topo_sort(int vertices, const EdgeList& edges) const;
 
     /**