diff --git a/llvm/lib/CodeGen/RegAllocSimple.cpp b/llvm/lib/CodeGen/RegAllocSimple.cpp
index 57f3f5d..f6a9a11 100644
--- a/llvm/lib/CodeGen/RegAllocSimple.cpp
+++ b/llvm/lib/CodeGen/RegAllocSimple.cpp
@@ -25,6 +25,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
+#include <iostream>
 using namespace llvm;
 
 namespace {