Changes to build successfully with GCC 3.02


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1503 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/PostDominators.cpp b/lib/Analysis/PostDominators.cpp
index 2ed02db..2e4f6e4 100644
--- a/lib/Analysis/PostDominators.cpp
+++ b/lib/Analysis/PostDominators.cpp
@@ -10,6 +10,8 @@
 #include "Support/DepthFirstIterator.h"
 #include "Support/STLExtras.h"
 #include <algorithm>
+using std::set;
+
 
 //===----------------------------------------------------------------------===//
 //  Helper Template